Subjects -> AGRICULTURE (Total: 981 journals)
    - AGRICULTURAL ECONOMICS (93 journals)
    - AGRICULTURE (680 journals)
    - CROP PRODUCTION AND SOIL (120 journals)
    - POULTRY AND LIVESTOCK (58 journals)

AGRICULTURE (680 journals)            First | 1 2 3 4     

Showing 201 - 263 of 263 Journals sorted by number of followers
Biodiversity     Hybrid Journal   (Followers: 27)
Agriculture & Food Security     Open Access   (Followers: 21)
Future of Food : Journal on Food, Agriculture and Society     Open Access   (Followers: 20)
African Journal of Food, Agriculture, Nutrition and Development     Open Access   (Followers: 18)
Nature Plants     Full-text available via subscription   (Followers: 17)
Advances in Agriculture     Open Access   (Followers: 15)
Agricultural History Review     Full-text available via subscription   (Followers: 15)
Indian Journal of Agricultural Sciences     Open Access   (Followers: 12)
Biological Agriculture & Horticulture : An International Journal for Sustainable Production Systems     Partially Free   (Followers: 11)
Journal of Land and Rural Studies     Hybrid Journal   (Followers: 11)
Advances in Life Science and Technology     Open Access   (Followers: 11)
Agriculture and Food Sciences Research     Open Access   (Followers: 10)
Agricultural Research     Hybrid Journal   (Followers: 10)
Indian Horticulture     Full-text available via subscription   (Followers: 9)
Culture, Agriculture, Food and Environment     Hybrid Journal   (Followers: 8)
Arboricultural Journal : The International Journal of Urban Forestry     Hybrid Journal   (Followers: 7)
Aceh International Journal of Science and Technology     Open Access   (Followers: 7)
Invertebrate Reproduction & Development     Hybrid Journal   (Followers: 6)
Journal of Agriculture and Sustainability     Open Access   (Followers: 6)
Journal of Agriculture and Social Research (JASR)     Open Access   (Followers: 6)
New Journal of Botany     Hybrid Journal   (Followers: 6)
Journal of Agriculture, Forestry and the Social Sciences     Full-text available via subscription   (Followers: 6)
International Journal of Agriculture and Forestry     Open Access   (Followers: 6)
Acta Scientiarum. Animal Sciences     Open Access   (Followers: 5)
Journal of Advances in Agriculture     Open Access   (Followers: 5)
American Journal of Rural Development     Open Access   (Followers: 5)
EvoDevo     Open Access   (Followers: 5)
Cereal Chemistry     Full-text available via subscription   (Followers: 4)
Acta Agrobotanica     Open Access   (Followers: 4)
Italian Journal of Agronomy     Open Access   (Followers: 4)
Journal of Agricultural Science     Open Access   (Followers: 4)
EU Agrarian Law     Open Access   (Followers: 4)
Studies in Australian Garden History     Full-text available via subscription   (Followers: 4)
Journal of Agriculture and Rural Development in the Tropics and Subtropics     Open Access   (Followers: 4)
Tanzania Journal of Agricultural Sciences     Open Access   (Followers: 4)
Journal of Modern Agriculture     Open Access   (Followers: 4)
Journal of Agriculture and Natural Resources Sciences     Open Access   (Followers: 3)
Journal of the Ghana Science Association     Full-text available via subscription   (Followers: 3)
Journal of Science and Technology (Ghana)     Open Access   (Followers: 3)
Journal of Agricultural Extension and Rural Development     Open Access   (Followers: 3)
Biocatalysis and Agricultural Biotechnology     Hybrid Journal   (Followers: 3)
Sustainable Agriculture Research     Open Access   (Followers: 3)
Food and Energy Security     Open Access   (Followers: 3)
International Journal of Agricultural Research, Innovation and Technology     Open Access   (Followers: 3)
International Journal of Applied Agriculture and Apiculture Research     Open Access   (Followers: 3)
Agra Europe     Full-text available via subscription   (Followers: 3)
Journal of Agricultural Chemistry and Environment     Open Access   (Followers: 3)
Asian Journal of Medical and Biological Research     Open Access   (Followers: 3)
Acta Universitatis Sapientiae, Alimentaria     Open Access   (Followers: 3)
Journal of Essential Oil Research     Hybrid Journal   (Followers: 3)
Diatom Research     Hybrid Journal   (Followers: 3)
Journal of Agricultural Extension     Open Access   (Followers: 2)
Nigerian Food Journal     Full-text available via subscription   (Followers: 2)
International Journal for Parasitology : Parasites and Wildlife     Open Access   (Followers: 2)
Agricultura Tropica et Subtropica     Open Access   (Followers: 2)
Journal of Apicultural Science     Open Access   (Followers: 2)
International Journal of Agricultural Management and Development     Open Access   (Followers: 2)
Ciencia forestal en México     Open Access   (Followers: 2)
Revista Cubana de Ciencia Agrícola     Open Access   (Followers: 2)
Journal of Agriculture and Food Sciences     Full-text available via subscription   (Followers: 2)
Tropical Agricultural Research and Extension     Open Access   (Followers: 2)
Rural China     Hybrid Journal   (Followers: 2)
Rural Sustainability Research     Open Access   (Followers: 2)
Journal of Biology, Agriculture and Healthcare     Open Access   (Followers: 2)
Agro-Science     Full-text available via subscription   (Followers: 2)
Ghana Journal of Agricultural Science     Full-text available via subscription   (Followers: 2)
New Zealand Journal of Agricultural Research     Hybrid Journal   (Followers: 2)
Tropical Agricultural Research     Open Access   (Followers: 2)
Journal of Sustainable Society     Open Access   (Followers: 2)
Journal of Food Security     Open Access   (Followers: 2)
Journal of Agricultural Engineering     Open Access   (Followers: 2)
Revista Verde de Agroecologia e Desenvolvimento Sustentável     Open Access   (Followers: 2)
Huria : Journal of the Open University of Tanzania     Full-text available via subscription   (Followers: 2)
Buletin Peternakan : Bulletin of Animal Science     Open Access   (Followers: 1)
Berkala Ilmiah Pertanian     Open Access   (Followers: 1)
Journal of Agricultural Studies     Open Access   (Followers: 1)
RIA. Revista de Investigaciones Agropecuarias     Open Access   (Followers: 1)
Agricultural Commodities     Full-text available via subscription   (Followers: 1)
Journal of Agricultural Engineering     Full-text available via subscription   (Followers: 1)
Jurnal Veteriner     Open Access   (Followers: 1)
Archivos de Zootecnia     Open Access   (Followers: 1)
Journal of Natural Sciences Research     Open Access   (Followers: 1)
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca : Food Science and Technology     Open Access   (Followers: 1)
Wartazoa. Indonesian Bulletin of Animal and Veterinary Sciences     Open Access   (Followers: 1)
Research in Agriculture, Livestock and Fisheries     Open Access   (Followers: 1)
COCOS : The Journal of the Coconut Research Institute of Sri Lanka     Open Access   (Followers: 1)
Emirates Journal of Food and Agriculture     Open Access   (Followers: 1)
Frontiers in Science     Open Access   (Followers: 1)
Global Approaches to Extension Practice : A Journal of Agricultural Extension     Full-text available via subscription   (Followers: 1)
Chemical and Biological Technologies for Agriculture     Open Access   (Followers: 1)
Progressive Agriculture     Open Access   (Followers: 1)
Folia Horticulturae     Open Access   (Followers: 1)
Rivista di Studi sulla Sostenibilità     Full-text available via subscription   (Followers: 1)
Journal of Science Foundation     Open Access   (Followers: 1)
Annals of Agricultural Sciences     Open Access   (Followers: 1)
Avances en Investigacion Agropecuaria     Open Access   (Followers: 1)
International Journal of Sustainable Agricultural Management and Informatics     Hybrid Journal   (Followers: 1)
Bangladesh Journal of Agricultural Research     Open Access   (Followers: 1)
Journal of Agricultural Sciences     Open Access   (Followers: 1)
Jurnal Ilmu dan Kesehatan Hewan (Veterinary Science and Medicine Journal)     Open Access   (Followers: 1)
Arquivos do Instituto Biológico     Open Access   (Followers: 1)
International Journal of Recycling of Organic Waste in Agriculture     Open Access   (Followers: 1)
International Journal of Agricultural Extension     Open Access   (Followers: 1)
Innovare Journal of Agricultural Science     Open Access   (Followers: 1)
International Journal of Agriculture System     Open Access   (Followers: 1)
Acta Technologica Agriculturae     Open Access   (Followers: 1)
Plant Knowledge Journal     Open Access   (Followers: 1)
Iranian Journal of Applied Animal Science     Open Access   (Followers: 1)
Journal of Degraded and Mining Lands Management     Open Access   (Followers: 1)
Revista Brasileira de Higiene e Sanidade Animal     Open Access   (Followers: 1)
Science, Technology and Arts Research Journal     Open Access   (Followers: 1)
Nigerian Journal of Technological Research     Full-text available via subscription   (Followers: 1)
Social and Natural Sciences Journal     Open Access  
Jurnal Agroteknologi     Open Access  
Perspectivas Rurales Nueva Época     Open Access  
Organic Farming     Open Access  
Research Ideas and Outcomes     Open Access  
Jurnal Udayana Mengabdi     Open Access  
Landtechnik : Agricultural Engineering     Open Access  
International Letters of Natural Sciences     Open Access  
Agrociencia Uruguay     Open Access  
Heliyon     Open Access  
Ciência e Técnica Vitivinícola     Open Access  
Oilseeds and fats, Crops and Lipids     Open Access  
Annals of Silvicultural Research     Open Access  
Pastura : Journal Of Tropical Forage Science     Open Access  
Journal of Citrus Pathology     Open Access  
Revista Iberoamericana de las Ciencias Biológicas y Agropecuarias     Open Access  
Kansas Agricultural Experiment Station Research Reports     Open Access  
International Journal of Secondary Metabolite     Open Access  
Scientia Agropecuaria     Open Access  
Pelita Perkebunan (Coffee and Cocoa Research Journal)     Open Access  
Revista de Agricultura Neotropical     Open Access  
Cogent Food & Agriculture     Open Access  
Fave : Sección ciencias agrarias     Open Access  
Revista de Ciências Agrárias     Open Access  
Review of Agrarian Studies     Open Access  
Nigerian Journal of Biotechnology     Open Access  
Nigeria Agricultural Journal     Full-text available via subscription  
Annales des Sciences Agronomiques     Full-text available via subscription  
Journal of the Bangladesh Agricultural University     Open Access  
Journal of Buffalo Science     Hybrid Journal  
Revista de Ciências Agroveterinárias     Open Access  
Tropical Grasslands - Forrajes Tropicales     Open Access  
Research in Plant Sciences     Open Access  
World Journal of Agricultural Research     Open Access  
Universal Journal of Agricultural Research     Open Access  
Research & Reviews : Journal of Agriculture Science and Technology     Full-text available via subscription  
Revue Marocaine des Sciences Agronomiques et Vétérinaires     Open Access  
Nativa     Open Access  
SAARC Journal of Agriculture     Open Access  
West African Journal of Applied Ecology     Open Access  
Journal of Agricultural Research and Development     Full-text available via subscription  
Journal de la Recherche Scientifique de l'Universite de Lome     Full-text available via subscription  
Global Journal of Agricultural Sciences     Full-text available via subscription  
Agrosearch     Open Access  
Agronomie Africaine     Full-text available via subscription  
Professional Agricultural Workers Journal     Open Access  
Interciencia     Open Access  
Nepal Journal of Science and Technology     Open Access  
Journal of the Saudi Society of Agricultural Sciences     Open Access  
Information Processing in Agriculture     Open Access  
Sabaragamuwa University Journal     Open Access  
Ceiba     Open Access  
Research in Sierra Leone Studies : Weave     Open Access  
The Agriculturists     Open Access  
La Calera     Open Access  
Selçuk Tarım ve Gıda Bilimleri Dergisi     Open Access  
Revista de la Universidad del Zulia     Open Access  
Journal of Arid Land     Hybrid Journal  
Rangifer     Open Access  
Encuentro     Open Access  
Journal Of Agrobiotechnology     Open Access  
Coffee Science     Open Access  
Bangladesh Journal of Scientific Research     Open Access  
Landbohistorisk Tidsskrift     Open Access  
Biotecnología en el Sector Agropecuario y Agroindustrial     Open Access  
Walailak Journal of Science and Technology     Open Access  
Universidad y Ciencia     Open Access  
Tropical and Subtropical Agroecosystems     Open Access  
Terra Latinoamericana     Open Access  
Revista Iberoamericana de Tecnologia Postcosecha     Open Access  
Revista Brasileira de Ciências Agrárias     Open Access  
Multiciencias     Open Access  
Ensaios e Ciência : Ciências Biológicas, Agrárias e da Saúde     Open Access  
Bioagro     Open Access  
Agroalimentaria     Open Access  
Revista Mexicana de Ciencias Agrícolas     Open Access  
Revista U.D.C.A Actualidad & Divulgación Científica     Open Access  
Revista Ciencias Técnicas Agropecuarias     Open Access  
Revista Chapingo. Serie horticultura     Open Access  
Pastos y Forrajes     Open Access  
Fitosanidad     Open Access  
Cultivos Tropicales     Open Access  
Cuadernos de Desarrollo Rural     Open Access  
Ciencia e Investigación Agraria     Open Access  
Agronomía Mesoamericana     Open Access  
Agronomía Costarricense     Open Access  
Agrociencia     Open Access  
Agrivita : Journal of Agricultural Science     Open Access  

  First | 1 2 3 4     

Similar Journals
Journal Cover
Tropical and Subtropical Agroecosystems
Journal Prestige (SJR): 0.171
Number of Followers: 0  

  This is an Open Access Journal Open Access journal
ISSN (Online) 1870-0462
Published by Universidad Autónoma de Yucatán Homepage  [2 journals]
  • Cover Vol. 25, No. 3

    • Authors: . .
      PubDate: 2022-09-06
      Issue No: Vol. 25, No. 3 (2022)
  • BIOFERTILIZERS IN MEXICAN LIME (Citrus aurantifolia (Christm.) Swingle):

    • Authors: Marcela Ríos-Sandoval, Gabriel Rincón-Enríquez, Martha Angélica Bautista-Cruz, Evangelina Esmeralda Quiñones Aguilar
      Abstract: Background: The majority of terrestrial plants have evolved in symbiosis with beneficial microorganisms, which help them acquire minerals that are scarce in soil, such as phosphorus and in some cases nitrogen. Thus, the development and use of biofertilizers based on microorganisms is important for partial or total replacement of chemical fertilizers. The use of arbuscular mycorrhizal fungi (AMF) and Azospirillum brasilense helps to boost Mexican lime (Citrus aurantifolia) plant growth, making them more vigorous and productive. Objective: To evaluate the effect of beneficial microorganisms in Mexican lime plant growth in a greenhouse. Methodology: An experiment with Mexican lime was established under greenhouse conditions and a completely randomized bifactorial design: (A) beneficial microorganism with four levels: consortium HMA Cerro del Metate; Rhizophagus intraradices (Ri); Azospirillum brasilense (Ab); and without microbial inoculum (WI); (B) chemical fertilization N-P-K (nitrogen-phosphorus-potassium) with four levels: high (180-180-180 kg ha-1); intermediate (90-90-90 kg ha-1); low (45-45-45 kg ha-1) and without fertilization. In total, 16 treatments with seven replicates were performed; plant growth and microbiological response variables were evaluated with an analysis of variance (ANOVA) and Tukey’s multiple comparison of means tests. Results: Significant effects (Tukey, P≤0.05) of the mycorrhizal consortium Cerro del Metate were found, followed by R. intraradices and lastly A. brasilense, which proved that these microorganisms promoted plant growth. Mycorrhization significantly increased (P≤0.05) plant growth rate, as well as dry biomass, observing a mycorrhizal colonization from 16 to 30%. Fertilization only showed a significant interaction (Tukey, P≤0.05) with A. brasilense. Implications: The use of native microorganisms and preferably consortia may have better adaptability than commercial ones, which can be explained in part by the effects found in this study. Conclusion: Mexican lime plants showed a significantly positive (P≤0.05) response to inoculation with AMF, showing greater plant growth than the other treatments.
      PubDate: 2022-09-05
      DOI: 10.56369/tsaes.4246
      Issue No: Vol. 25, No. 3 (2022)
           PENIPE, ECUADOR 2021

    • Authors: Juan Pablo Haro Altamirano, Miguel Angel Osorio Rivera, Marco Anibal Vivar Arrieta, Sandra Patricia Jácome Tamayo, Justo Moises Narváez Brito
      Abstract: Background: the agricultural production system, its operation, monitoring and execution, requires formulating new evaluation schemes. Integrating the vast majority of social, cultural, ecological, economic, geopolitical characteristics and factors related to the technology applied in production systems. Through the use of associated indicators in each of its dimensions and attributes, to analyze its sustainability. The objective: This research is the evaluation of the sustainability of the production systems of family farming in the Penipe canton. That demands the selection, transformation and aggregation of economic, environmental, geopolitical, cultural and social indicators, which allow determining trends of the system, using a systemic, participatory, interdisciplinary and flexible approach called the MESMIS framework. Methodology: MESMIS was applied to nine representative farms of diversified, specialized and subsistence family farming production system. By determining the critical points, the indicators were applied once standardized and weighted. Results: Specialized family farming production system is sustainable with a score of (1.56), diversified family farming is moderately sustainable with a score of (1.32) and subsistence family farming, with a value of (0.77) is considered an unsustainable system within the locality. Implications: It was found that there are some aspects that limit the farms to be considered as sustainable systems, identifying the attributes to improve. In order to improve subsistence family farming, it is necessary to work on the following parameters: productivity, stability, resilience, reliability, adaptability, equity and self-management; diversified family farming expresses the following attributes to improve: productivity, stability, resilience, reliability, equity and self-management and specialized family farming has to improve in: Productivity, resilience, stability, equity. Conclusions: This evaluation responds to a cyclical process that, by effectively integrating the evaluation in the decision-making process, improves the probability of success in the design of alternatives to improve the productive systems in the Penipe canton.
      PubDate: 2022-09-02
      DOI: 10.56369/tsaes.4331
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Vidal César Vidal Aquino Zacarías, Andrés Alberto Azabache Leyton, Narcizo Isidoro Gómez Villanes, Jorge Jiménez Dávalos, Rember Pinedo-Taco
      Abstract: Background. The associations of poaceae and fabaceae forage species are important to provide cattle with a balanced diet between proteins and carbohydrates; also to contribute to the sustainable management of soils. Objective. The objective of the research was to determine the effect of the natural biostimulant on the triticale forage components during staggered sowing associated with faba bean. Methodology. The research was carried out under a randomized complete block experimental design with three repetitions. The genetic material was a line of semi-late triticale and a local variety of faba bean. Applications of a biostimulant were made in two phenological of the triticale stages forage during the staggered sowing (0, 20 and 40 days after sowing the bean). The variables evaluated were percentage increase of foliar N in triticale, biomass in triticale and broad bean, green forage yield of triticale and faba bean, presence of Rhizobium nodules in faba bean and interspecific competition indices of the associated system. Implications. The establishment of a triticale-faba bean association requires certain planting arrangements, varieties and nutrition to avoid the effects of competition, which cause the dominance or displacement of any of the species. Conclusions. The application of biostimulant in triticale in the tillering stage 20 days after sowing the bean, the highest yield of triticale forage was found, allowing the increase in the concentration of foliar nitrogen (1.8%) and rhizobial nodules per plant (175.83) of broad bean; higher biomass (6.49 t ha-1) in triticale and higher amount of total forage (39.02 t ha-1). The competition indices indicate that the bean cultivation in association favors the total relative yield without showing aggressive behavior between crops (A = 0); triticale and faba bean share their competitive capacity (CR>1) according to staggered plantings with and without biostimulant in a certain phenological state of triticale.
      PubDate: 2022-09-02
      DOI: 10.56369/tsaes.3941
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Dixan Pozo-Leyva, Felipe López-González, Rafael Olea-Pérez, Patricia Balderas Hernández, Fernando Casanova-Lugo, Carlos Manuel Arriaga-Jordán
      Abstract: Background: Nitrogen (N) plays an important role within milk production systems (MPS), as an indicator of environmental and economic efficiency. Objective. The objective was to determine utilisation of N offered in the ration and estimate GHG from the enteric fermentation and manure management in 12 small-scale dairy farms under two feeding strategies. Methodology. Six farms had their herds in confinement under a cut-and-carry feeding system, and six farms implemented day grazing of mixed pastures, both systems used commercial concentrates as a supplement. Cows in milk production and their replacements were considered in the study. Pasture intake was calculated by difference in dry matter intake, using 3.2 % of live weight as intake factor. The N utilisation was determined by difference between N intake and excretion at each farm during a whole year operation. The GHG emissions were estimated following Tier 2 guidelines rom IPCC. Differences in feeding strategies were analysed with a completely random block design using farms as a blocking factor. Results. Mean farm size was 5.0 ha for cut-and-carry and 16.0 ha for grazing, and dry matter feed self-sufficiency was 62 and 83% respectively, considering 12% and 22% refusals for each strategy. There were no statistically significant differences (P>0.05) for any of the N utilisation components (N in diet, N in milk, N in manure, NH3 and N2O or GHG emissions. Implications. This is a novel report on assessing N fluxes and GHG emissions from small-scale dairy systems in Mexico and Latin America. Conclusions. In general, 87.6% of the N consumed is excreted in manure and urine. The feeding strategies did not diverge enough to have an impact on GHG emissions.
      PubDate: 2022-09-02
      DOI: 10.56369/tsaes.3986
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Ayodeji Damilola Kehinde, Adebayo Akinola, Ayodeji Damilola Kehinde, Abiodun Akintunde Ogundeji
      Abstract: Background. As part of efforts to reduce soil degradation and improve agricultural yield, farmers in the study area learned about various soil conservation practices through agricultural organizations. Objective. This study, therefore, investigated the impact of agricultural organizations on the adoption of soil conservation practices. Methodology. Through a multi-stage sampling procedure, the data collected were analyzed with the aid of descriptive statistics and a double hurdle regression model. Results. The descriptive results revealed that three conservation practices were majorly adopted in the study area, namely, cover crop (25 adopters), vegetative fallow (63 adopters) and mulch (83 adopters). The result further revealed significant differences in some socioeconomic characteristics between the categories of adopters in the study area, such as the age of the farmers, off-farm income, farming experience and the household size. However, the study concluded that the majority of the smallholder farmers were male, small scale and at their productive age. According to the first hurdle, the factors responsible for the adoption of the three soil conservation practices were; off-farm income, extension contact, farm size, years of education and membership in the agricultural organization. In the same vein, the factors that contributed to the intensity of soil conservation practices were membership of the agricultural organization, farm size, location of a valley on the farm land and household size. Implications. The paper adds evidence for a better understanding of the nexus between the agricultural organisation and the adoption of soil conservation practices. Conclusion. Based on these findings, the study recommends encouraging the training and strengthening of agricultural organizations for better adoption of soil conservation practices. In addition, effective strategies, programs and institutional structures that improve farmers' education, the frequency of extension contacts and off-farm income should be established.
      PubDate: 2022-09-02
      DOI: 10.56369/tsaes.4148
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Norma Carolina Valverde-Reyes, Rember Pinedo-Taco
      Abstract: Background. The area under sweet potato cultivation on the Peruvian coast has grown in the last 10 years due to increased market demand; however, its level of sustainability is unknown due to crop intensification. Objective. To determine the level of sustainability of sweet potato production units (SPU), considering economic, environmental and social aspects, applying multivariate analysis techniques and methodological proposals. Methodology. Surveys with structured questions were applied to farmers responsible for managing their SPU. The values of the economic, environmental and social indicators were found according to a methodological proposal of multidimensional analysis. The data were adapted to an ordinal scale from 1 to 5, in which 1 was considered the least sustainable and 5 an ideal level of sustainability. Implications. The value of economic, environmental and social indicators determines the level of sustainability of agricultural production systems. Conclusions. The economic, social and environmental indicators contribute with a General Sustainability Index (GSI) of 2.93; value that places the SPU in a critical condition due to the fact that the value of the environmental indicators fails to exceed the minimum sustainability threshold established in the applied methodology.
      PubDate: 2022-09-02
      DOI: 10.56369/tsaes.4295
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: María José García-Castillo, Luis Carlos Rodríguez-Zapata, Lorenzo Felipe Sanchez Teyer
      Abstract: Background: Cellulose synthase is a superfamily where genes involved in the synthesis of the primary and secondary cell wall and their relationship with plant fibers have been reported. In recent years, vegetable fiber has been the subject of considerable interest, due to its quality and the ability to be biodegradable, and it has been reported that the cellulose content is related to the quality of the fiber. Objective: To determine the relationship of CesA genes with fiber content in Agave fourcroydes Lem. Methodology: The relative expression of the CesA3, CesA4 and CesA5 genes involved in the primary and secondary cell wall will be prolonged and their relationship with fiber content will be evaluated in plants of different heights in a henequen plantation. The content of the fiber components was evaluated using the TAPPI methods and an analysis of variance (ANOVA) was performed, the means were compared using the Tukey test (p≤ 0.05). Results: Plants with greater height, have longer leaves, with higher cellulose content (48%) and low content of hemicellulose (3%) and lignin (8%), these characteristics are related to high levels of relative expression of the CesA3 and CesA4 genes and low relative expression level of the CesA5 gene. Implications: A direct connection of higher expression of CesA3 and CesA4 genes with the length of the leaves, the height of the plant and the cellulose content is presented. Conclusions: In this research, the exploration between the expression and the length of the leaves serves as a basis for future research focused on the early selection of individuals with high cellulose content, which through plant tissue culture represents an option for genetic improvement for the benefit of crop producers.
      PubDate: 2022-09-02
      DOI: 10.56369/tsaes.4328
      Issue No: Vol. 25, No. 3 (2022)
           Pasteuria penetrans

    • Authors: David Enrique Lindo Seminario, Sandra Mendez Farroñan, Jorge Canta Ventura, José Córdova Campos, Carlos Condemarín Montealegre, Savina Gutiérrez Calle, Arturo Morales Pizarro, Eric Mialhe Matonnier
      Abstract: Background: Pasteuria penetrans is a nonculturable bacterium that obligately parasitizes several species of phytopathogenic nematodes. Unknown endogenous female, plant or microbial reproductive factors are indispensable for multiplication and endospore formation of P. penetrans. Objective: To characterize P. penetrans endospores by 16S rRNA gene sequencing in samples from infected adult female Meloidogyne javanica and microbiota of infected and uninfected adult female M. javanica with P. penetrans by high-throughput sequencing of the V4 hypervariable region of the 16S rRNA gene. Methodology: Infected roots were collected from grapevines; fresh infective juvenile nematodes (J2) were extracted for P. penetrans endospore fixation and inoculation into tomato plants. Genomic and metagenomic DNA from infected and uninfected adult females of M. javanica was extracted for sequencing by sequencing the V4 region of the 16S rRNA gene of P. penetrans and its bacterial microbiome. The generated sequences were processed using bioinformatics software for analyses of alpha and beta diversity indices of the bacterial microbiome. Results: An amplicon of 550 base pairs with 98% identity and homology to P. penetrans was obtained. The taxonomic profile revealed the highest bacterial diversity and richness in the microbiota related to infected adult females, with Proteobacteria occurring in both samples between 45 and 83%, followed by Firmicutes, Actinobacteria and Bacteroidetes with 19, 11 and 8% respectively at the phylum level. Likewise, the most abundant genera associated with the native microbiota of the adult nematode were identified as Pseudomonas, Flavobacterium and Chitinophaga at 82.5, 15 and 2%, respectively. In infected females, Paenibacillus, Pasteuria, Pseudomonas and Streptomyces were recorded with 45, 7, 6 and 5% respectively, the most abundant. Implications: The results suggest the existence of bacterial genera in infected M. javanica females involved in the in vivo development of P. penetrans endospores. Conclusions: This would reveal a reduction of Pseudomonas dominance favoring the colonization of different bacteria that cohabit with P. penetrans, being this change in the microbial composition a possible factor that favors the multiplication of P. penetrans endospores within the host.
      PubDate: 2022-09-02
      DOI: 10.56369/tsaes.4341
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Roberto Hugo Tirado Malaver, Roberto Tirado-Lara, Nayla Fabian-Anastacio
      Abstract: Background: Sweet potato (Ipomoea batatas L.) is a crop of great importance in social, economic and industrial terms due to its forage aptitude, high yield potential and quality of storage roots, necessary as human food and also as raw material for bioethanol production a promising substitute for fossil fuels or to boost alcohol production. Objective: To compare improved sweetpotato clones under different growing seasons and to select a promising new cultivar with high yield potential and bioethanol production from storage roots in Peru. Methodology: The combined analysis of variance was used during two seasons (summer and spring) in Lambayeque, Peru. The yield of storage roots was evaluated, with respect to the quality, the percentage of dry matter and the production of bioethanol were evaluated, which was analyzed by the enzymatic hydrolysis of the starch of four clones and a control variety. Results: The combined analysis of variance shows that the clones presented a significant effect on the variables under study. Likewise, the clone CIP 199071.8 with the highest yield of storage roots was identified during season 1 (summer) with an average of 67.4 ± 1.2 t ha-1 and in season 2 (spring) with 73.4 ± 0, 8 t ha-1 regarding the combined analysis obtained 70.4 ± 1.1 t ha-1. In addition, the present clone with an average of 28.9 ± 1.4% of dry matter stands out statistically, in fact the same clone 199071.8 reported the highest bioethanol production in season 1 (summer) with an average of 7089.6 ± 2, 2 L ha-1 of bioethanol and in season 2 (spring) it reached the highest bioethanol production with an average of 7875.1 ± 1.9 L ha-1. Regarding the combined analysis, it obtained 7553.2 ± 1.7 L ha-1 of bioethanol. Implications: The sweet potato clones had a significant effect on the yield and quality of the storage roots, a necessary source for human food or industrial input. Conclusion: The clone CIP 199071.8 reached the highest yield of storage roots, dry matter and bioethanol production during the two growing seasons (summer 2019 and spring 2019), therefore, it will be released as a new cultivar.
      PubDate: 2022-09-02
      DOI: 10.56369/tsaes.4409
      Issue No: Vol. 25, No. 3 (2022)
           YUCATAN, MÉXICO

    • Authors: J.A. Couoh-Moo, José Bernardino Castillo Caamal, B.A. Balam-Cocom, J.A. Caamal-Maldonado
      Abstract: Background. The effect of soil fertility and productivity depletion on the milpa system is, in most cases, compensated with the use of agrochemicals, which can be unsustainable on the long-term. Agroecological practices, such as the use of organic inputs, can contribute to sustainable production. Objective: To evaluate the effect of the application of the liquid fermented from native microorganisms (boil NM) and fertilization type (FT), on yield of corn and their components. Methodology: The corn var. "Santa Rosa" was established during the spring-summer cycle of 2018 in Xoy, Peto, Yucatan, Mexico. The experimental design consisted of randomized blocks with an arrangement in split plots; the large plot was the FT with three levels: control (CON), diammonium phosphate (DAP) and sheep manure (SM); the small plot was spraying of boil NM at two levels: 0 mL L-1 and 100 mL L-1. The dependent variables were: grain yield, number of cobs, kernel specific weight, and final height of the plant. The variables were analyzed with procedure PROC GLM statistical software SAS version 2013. Results: All variables were statistically similar (P>0.05), except the kernel specific weight in the treatment of NM spraying. Consecuently, the means comparison test was not undertaken. The variable means were: grain yield, 4750 kg ha-1; number of cobs 27992 ha-1; kernel specific weight, 314.16 mg grano-1; and height of the plant, 276.5 cm. The NM spraying increased the kernel weight by 24.5% (P<0.05). Implications: Although,the effect of sheep manure on grain yield was similar to that found with chemical fertilizers, it has the advantage that it is available at the farm. In adition, the use of MN increased the weight of kernel. Conclusions: The application of either TF or MN and the interactions between these factors resulted in similar responses on the studied variables, except the effect of MN on the specific weight of the grain. It is suggested to continue the evaluation of the application of MN and TF in the management of the milpa system in several crop cycles to evaluate this organic input in a long term.
      PubDate: 2022-09-02
      DOI: 10.56369/tsaes.4225
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Emerita Ndwiga Njiru, Mary Baaru, Charles Gachene
      Abstract: Background: Terraces are structures consisting of ditches and embankments used to control erosion and increase land productivity. There is, however, little emphasis on the effects of the ditch dimensions on soil moisture and nutrient dynamics. Objective: To determine the effect of varying ditch depths on soil moisture and nutrient quantities and their variability within the terrace slope on hard-setting soils. Methodology: Soil samples were collected seasonally in 2014 and 2015 from terraces with different ditch depths (60, 30, and 0 [control] cm) for the determination of soil moisture content (SMC). The samples were collected from the upper, middle and lower slope positions of each terrace. Soil from the three slope positions of each terrace was also sampled at the end of the study and analyzed for total nitrogen (%TN), available phosphorous (Av. P), exchangeable potassium (K+) and % organic carbon (OC) contents. Data were subjected to a two-way analysis of variance and differences in means determined at a 95% level of confidence. Results: Significant interactions (P<0.001) in SMC were observed between seasons, ditch depths and slope positions. Higher SMC was found in treatments with 30 and 60 cm ditch depths in all the slope positions and seasons compared to the control. Soil moisture contents in the lower and upper slope positions were significantly different between the terraces with 30 and 60 cm ditch depths when rainfall was high and evenly distributed, but non-significant in poorly distributed rainfall seasons. Significant differences (P ≤ 0.05) in contents of total nitrogen and available phosphorous were found between the upper and lower slope positions of the terraces with ditches. Implications: The effect of ditch depths on moisture, total nitrogen and available phosphorous contents and their variability within the slope depended on the amount and distribution of rainfall. Conclusion: Construction of terraces with shallow ditch depths (of 30 cm) is recommended to conserve soil moisture and nutrients nitrogen and phosphorous on hard-setting soils in the marginal areas of semi-arid Eastern Kenya. 
      PubDate: 2022-08-25
      DOI: 10.56369/tsaes.4337
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Tomas Alexander Arbez-Abnal, José Roberto Sanginés-García, Angel Trinidad Piñeiro-Vazquez, Edgar Aguilar-Urquizo, Alfonso Juventino Chay Canul
      Abstract: Background: The identification of the relationship between the particular traits of the body development of the rabbit could help the understanding of the biological growth and the application in different areas of livestock and veterinary study. Objective. To evaluate the relationship between osteometry of the limbs, live weight (LW), hot carcass weight (HCW) and anatomical cuts; and generate equations to predict PV, PCC and anatomical cuts in New Zealand White (NZW) rabbits at different ages. Methodology. A total of 113 rabbits of seven different ages (9, 11, 14, 17, 20, 24 and 28 weeks) were used. The data obtained were LW, carcass characteristics: PCC and anatomical cuts (front, middle and back); and osteometry: length and diameter of the humerus (LH and DH), radio-ulna (LR-C and DR-C), femur (LF and DF) and tibia-fibula (LT-P and DT-P). The information was analyzed using Pearson's correlation coefficients (r) and linear and multiple regression models. The accuracy of the models was evaluated using the coefficients of determination (r2) and the square root of the mean square error (RCCME). Results. The correlations expressed between LW, carcass characteristics and bone lengths were higher (r= 0.90 – 0.95; p= < 0.0001) compared to diameters (r= 0.38 – 0.72; p= < 0.0001). The regression equations for PV had a RCCME that varied from 186.86 to 197.70 g using LR-C and LF. While for the PCC it presented RCCME from 130.4 to 138.58 g with LH, LR-C and DH. Regarding the anatomical cuts, the progressive order of rear, middle and front using LF and LH was RCCME= 21.66 to 25.67. The LF and LH explained 92 and 91% of the variation of the PV and PCC, although it decreased slightly in the anatomical cuts from 85 to 92%. Implications. The osteometry of the extremities reflects security in the application of equations to calculate general and particular data of body mass in the rabbit, this contribution of knowledge can be extrapolated for animal production and forensic veterinary studies. Conclusion. The close associations obtained between limb lengths (exception LT-P) with PV, PCC and anatomical cuts gave equations with high capacity to estimate these body changes of growing NZB rabbits.
      PubDate: 2022-08-25
      DOI: 10.56369/tsaes.4241
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Mónica Marcela Galicia Jiménez, Juan Manuel Pinos Rodríguez
      PubDate: 2022-08-17
      DOI: 10.56369/tsaes.4402
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Nahieli Silva - Cassani, Karen Fabiola Mancera, Jorge Canul, Luis Ramirez Aviles, Javier Solorio, Patricia Güereca, Francisco Galindo
      Abstract: Background. It is agreed that there is a need to work on sustainable extensive livestock production systems. Silvopastoral systems are an alternative for efficient and sustainable grazing systems to increase the provision of ecosystems services and minimize the environmental costs associated to monoculture systems (MS), but the efficiency of intensively managed (IS) and unmanaged or native (NS) silvopastoral systems has never been assessed and compared to MS. The Framework for Assessing the Sustainability of Natural Resource Management (MESMIS) offers a tool to assess sustainability criteria in agroecosystems. Objective. To use MESMIS to compare the sustainable performance of NS, IS and MS and determine the system with the best sustainable performance in the Mexican Tropics. Methodology. One MS IS and NS per municipality (Tizimin, Merida and Tzucacab) were evaluated in the state of Yucatán, Mexico. Based on the MESMIS approach, the evaluation of the critical points of sustainability resulted in the selection of 19 indicators classified according to the attributes also defined by MESMIS (production, adaptability, stability-resilience, equity and self-management) and by sustainability dimensions (environmental, animal welfare, economic and social). After evaluation, indicator scores were obtained and integrated into attributes and dimensions through the assignation of equitable, balanced weights (W). Finally, attribute and dimension scores were aggregated in amoeba graphs to facilitate visual interpretation. Results. NS were better for the dimensions ‘Environmental’ and ‘Economic’ and the attributes ‘Stability, ‘Reliability’and ‘Resilience,’ and ‘Production’. IS were best for the dimension ‘Animal Welfare’ and attributes ‘Adaptability’ and ‘Self-reliance’. MS were better for the ‘Social’ dimension and the ‘Equity’ attribute. Implications. The fact that IS appeared to be more sustainable than MS does not leave out the idea of considering NS as a better option for some criteria such as the biodiversity conservation and the prevention of disease outbreaks, than IS. We suggest that more studies are carried on areas of potential improvement for IS as well as NS. Conclusions. This information will be useful to continue working on the parametrization of sustainability criteria of cattle extensive systems to be used for more efficient policies.
      PubDate: 2022-08-17
      DOI: 10.56369/tsaes.3556
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Blanca Lilia Gabriel Vejar, David Itzcoatl Marti­nez Herrera, Dinora Vázquez Luna, José Alfredo Villagómez Cortés, Otto Raúl Leyva Ovalle, Jorge Isaac Torres Barranca, Patricia Melendez Valadez
      Abstract: Background. Leptospirosis is a bacterial zoonosis caused by pathogenic species of the genus Leptospira that affects mainly reproductive performance in sheep. Objective. To identify the seroprevalence of Leptospira spp., associated serogroups, and possible risk factors in the state of Veracruz, Mexico. Methodology. Blood samples were collected from 405 sheep in 55 farms located in 13 municipalities distributed along three ovine-producing regions in the state. Serological diagnosis was made by Microscopic Agglutination Technique (MAT). The prevalence and its confidence intervals (CI) were calculated using Vassarstats software, the Odds Ratio (OR) values were estimated with WinEpiscope. Results. An overall seroprevalence of 53.83% (95%CI:48.84-58.75), per municipality of 100% (95%CI :71.66-100) and per flock of 92.73% (95%CI: 81.58-97.65) were noted. The highest prevalence by region was 58.82% (95%CI:%:50.57-66.62) for Los Tuxtlas (p= 0.218) and per municipality 86.36% (95%CI:71.95-94.33) for Ángel R. Cabada. The predominant serogroup was Hardjo (45.93%; 95%CI:41.02-50.92). By age, the highest values were 55.93% (95%CI:48.29-63.31) in the group of 19-36 months. The main recognized risk factors were region and municipality. Los Tuxtlas Region (OR =1.92; 95%CI:1.08-3.43) and the municipalities of Ángel R. Cabada (OR=15.5; 95%CI:5.1-47.2), Ayahualulco (OR=10.1; 95%CI :3.6-28.7), and Coatzintla (OR=6.1; 95%CI: 30.3 – 95.0). Implications. This study explores the presence of antibodies against Leptospira spp. in sheep, its associated serogroups and risk factors in the state of Veracruz, Mexico. This is this first report on the presence and relevance of this infection in sheep of this region. The role of sheep as a maintenance host for Leptospira spp. in endemic areas is stressed. Conclusions. The study concludes that Leptospira spp. in sheep has an overall seroprevalence of 53.83% in the state of Veracruz, Mexico and several serogroups present.
      PubDate: 2022-08-17
      DOI: 10.56369/tsaes.4205
      Issue No: Vol. 25, No. 3 (2022)
           FUNGI AGAINST Amblyomma mixtum AND Rhipicephalus microplus TICKS

    • Authors: Dora Romero Salas, Jose Luis Bravo Ramos, Daniel Sokani Sánchez Montes, Carolina Cárdenas Amaya, Jannete Gamboa Prieto, Anabel Cruz Romero, Angelica Olivares Muñoz
      Abstract: Background: Rhipicephalus microplus and Amblyomma mixtum are the most important tick species affecting livestock in tropical areas. They can have a direct harmful effect on cattle and humans due to transmission of pathogens of tick-borne diseases (TBD). Entomopathogenic fungi have an important role in crop pest control. However, data concerning the efficacy of use of entomopathogenic fungicombinations are scarce. Objective: For this reason, in this study, the efficacy of commercial fungal combinations was assessed: Trishok® (Trichoderma harzianaum and Trichoderma virens) and Esporomax® (Beauveria bassiana, Metarhizium anisopliae, Paecelomyces fumosoroseus). Methodology: Adult immersion tests were performed with six different concentrations of fungal solutions. Results: In this study, Trishok® and Esporomax® showed potential efficacy against R. microplus. Different concentrations of fungal application tested on A. mixtum did not show any effect. The observed mortality of R. microplus was 85. 0 ± 2.0 and 65.0 ± 2.0 for Trishok® and Esporomax®, respectively. The estimated LC50 for R. microplus immersed in solutions of Trishok® and Esporomax® thereof were: 6.5x104 and3.9x105 conidia mL-1, respectively. Implications: These results should be considered in the design and implementation of alternatives based on the biological control of ticks. Conclusion: We can conclude that combined commercial strains of entomopathogenic fungi have in vitro acaricidal activity against R. microplus. 
      PubDate: 2022-08-15
      DOI: 10.56369/tsaes.3919
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Maribel Del Ángel Gerónimo, Claudio Vite Cristóbal, Juan Manuel Pech Canché, Eloísa Ortega Vargas, Armando Arrieta González
      Abstract: Background. Tantoyuca, Veracruz presents a great diversity of vegetation in the grasslands and its main economic activity is cattle ranching, in which two production systems are managed (dairy and meat). Objective. The objective was to assess the diversity and abundance of native and introduced vegetation present in the dairy and meat production systems of the grasslands of Tantoyuca, Veracruz, Mexico. Methodology. The floristic composition, structure, diversity, richness and conservation value were estimated from the inventory and abundance of plant species obtained by sampling by linear transects in ten dairy or meat grasslands. The Shannon and Simpson true diversity indices were generated and the relative abundances of the vegetation diversity were obtained. The relationship between species diversity and grasslands was performed with the ꭕ2 test. An inventory of pastures used in grasslands was represented on a vector map with the information obtained from 76 surveyed ranchers. Results. In the grasslands, 130 species, 107 genera and 50 families were identified, distributed in 68.5% herbs, 29.5% shrubs and 2% vines, and the similarity of plant diversity in both systems (dairy and meat) was evidenced. The most commonly used grasses are Urochloa decumbens Stapf and Cynodon nlemfuensis Vanderyst. The pastures were characterized by the low presence of introduced species (10) and a high diversity of native plants (120) used by livestock. In both systems there are high incidences of native legumes and species that indicate poor grazing management such as: Desmodium incanum (Sw.) DC. and Achyranthes aspera L. Implications. The information presented in this research is useful in the design of restoration plans with herbaceous and shrub vegetation, as well as serving as a basis for making management decisions for grazing with cattle in the grasslands of the Tantoyuca, Veracruz. Conclusion. Based on the sampling of herbaceous, shrub and vine vegetation, the high presence of native and naturalized species that can be used in the grasslands was highlighted. In the meat pastures of Tantoyuca, Veracruz, with the average biological value index and low species richness, it would be advisable to carry out repopulation practices with legumes and native and naturalized grasses.
      PubDate: 2022-08-15
      DOI: 10.56369/tsaes.4037
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Rodolfo Alejandro Martínez Soto, María Inés Yáñez Díaz, Israel Cantú Silva, Humberto González Rodríguez, José Guadalupe Marmolejo Moncicais
      Abstract: Background. The soil uses have been present since man domesticated the cultivated plants and, in the process, several changes in the soil’s physicochemical properties have been observed. Most of those changes have been detrimental to the soil’s productivity on a sustained basis. Thus, it is important to study and analyze the changes in soil’s physicochemical and hydraulic properties that get affections due to land conversion into different land-use systems. Objective. Assess the effect of different land-use systems on the physical, chemical, and hydrological properties of the soils in Northeast Mexico. Methodology. The study took place in a Chernozem soil in the Municipality of General Terán, Nuevo León, Mexico, and the land-use systems we investigated were: a citrus plantation, a grassland, an agricultural area, and the natural vegetation of the Tamaulipan Thornscrub site (MET) as a control treatment. Four composite soil samples were obtained from each site at two depths of 0-10 cm, and 10-30 cm, the chemical properties analyzed were pH and electrical conductivity (EC), and the physical properties consisted of Bulk density (BD), texture, total porosity (Tp), mechanical resistance to penetration (MRP) and field capacity (FC), permanent wilting point (PWP), available water (AW), initial infiltration (Ii), accumulated infiltration (Ai) and infiltration capacity (Ic). Results. The soil pH showed significant differences with depth (p=0.01), as well as the interaction of land-use depth (p=0.008), while electrical conductivity showed significant differences between land uses systems (p= 0.000); soil texture showed important differences in sand (p=0.003), silt (p=0.003) and clay content (p=0.006). There were significant differences between interaction of land-use soil depth, silt (p=0.003), and clay content (p=0.009). Soil hardness was significantly different between the diverse land-use systems (p=0.000). Concerning hydraulic properties, the water available in the place showed differences in land-use (p=0.001) and interaction land use-depth (p=0.006). Field capacity was also affected by land-use systems (p=0.000), as well as the interaction land use-depth (p=0.02); wilting point showed significant differences under distinct land use systems (p=0000), and in interaction of land use-depth (p=0003). Implications. More studies are needed in the short, medium and long term to monitor changes in physical, chemical, and water properties of soils under different land uses. Such information can be a guide in the proper management of these soils. Conclusion: From this study, it was possible to identify the negative impact that the different land-use systems have on the physical, chemical, and hydraulic properties of the soils under investigation. The hydraulic soil properties are the most affected. The information from this research can help for a better understanding of managing different land-use types in this Chernozem.
      PubDate: 2022-08-15
      DOI: 10.56369/tsaes.4115
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Adán Garcia Balbuena, Nicolás Torres Salado, Jerónimo Herrera Pérez, María de los ángeles Maldonado Peralta, Félix de Jesús Mayren Mendoza, Gabriel Mendoza Medel
      Abstract: Background. Given the production conditions in the resulting dry tropics, supplementation and use of protein sources is necessary. Objective. The objective of this study was to evaluate in vitro gas production, in vitro fermentation characteristics, productive response, ruminal characteristics, and apparent nutrient digestibility of a whole diet with sesame paste or soybean paste in calf feed. Methodology. In vitro total gas production was measured at 3, 6, 9, 12, 24, 48 and 72 hours. In addition, Eight Simbrah calves of 229 ± 39 kg live weight (LW) were fed a whole diet containing 10% soybean paste (control) or sesame paste (experimental). The study lasted 40 days and productive variables, nutrient digestibility and ruminal characteristics were determined. The experimental design was completely randomized. Results. Total gas production at 3 hours was 39% higher (p <0.05). in the control treatment, while at 6, 9, 12, 24, 48, 72 h and accumulated it was not different (p> 0.05). The dry matter intake (DMI) and the daily weight gain (DWA) did not change (p> 0.05) between treatments. In feed conversion (FC) the calves of the control treatment were 2.04% more efficient. Neutral detergent fiber digestibility was 3.9% higher (p <0.05) in calves fed sesame paste; while the digestibility of dry matter (DDM), organic matter, (DOM), acid detergent fiber (DADF), crude protein (DCP) and ruminal characteristics did not change (p> 0.05) between treatments. Implications. The use of sesame paste as a protein source gives a favorable productive response like soybean paste. Conclusion. The inclusion of sesame paste in whole calf diets can replace soybean paste in the whole calf diet in the tropics.
      PubDate: 2022-08-15
      DOI: 10.56369/tsaes.4155
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Paulino Sánchez Santillán, Adan Garcia Balbuena, Guadalupe Núñez Martínez, Nicolás Torres Salado, Jerónimo Herrera Pérez
      Abstract: Background. The production of ruminants in the tropics is based on the grazing of grasses, which present variations in their nutrient content depending on the intensity and frequency of cutting. Objective. To determine the effect of cutting intensity and regrowth age of the morphological composition of three hybrids of the genus Urochloa sp on gas production and in vitro gas production kinetics. Methodology. The samples were formed by the interaction of three morphological-hybrids (Cobra, Cayman and Mulato II-leaf and stem), two cutting intensities (10 and 15 cm) and 5 regrowth ages (7, 21, 35, 49 and 63 d). Partial and accumulated gas production, maximum volume (V), gas production rate (S) and Lag time (λ) were determined for the samples. The statistical design was a 6 x 2 x 5 factorial arrangement within a completely randomized design. Results. The leaves and stems of Cobra and Cayman showed the highest partial and cumulative in vitro gas production (p<0.05). The evaluated variables were not affected by the cutting intensity and the behavior in the in vitro tests was greater at 21 and 35 days of regrowth of the pastures. Implications. The cut intensity variable did not modify the mean values of the variables evaluated in this research work, while age negatively affects it. Conclusions. The leaves and stems of Cobra and Cayman grasses showed the highest partial and cumulative in vitro gas production.
      PubDate: 2022-08-15
      DOI: 10.56369/tsaes.4157
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Kelvin Mukhebi Wafula, Nancy Karanja, George N. Karuku, Anthony O. Esilaba
      Abstract: Background: Crop production in the arid and semi-arid lands (ASALs) is constrained by erratic rainfall and poor soil fertility. Therefore, climate smart agriculture mechanisms such as in-situ rainwater harvesting technologies and recommended fertilizer rates would be vital for ensuring food security. Objective: To evaluate selected in-situ water harvesting technologies and fertilizer rates on soil water content and yield of maize and beans at KALRO Katumani Research Center in Machakos County, Kenya during the 2019 and 2020 short and long rain seasons, respectively. Methodology: The experiment was established in a randomized complete block design with a split-split plot arrangement, replicated three times, with in-situ water harvesting technologies comprising of zai pits, ngolo pits, contour furrows and conventional tillage, as the main plots, whereas the split plots were varying rates of fertilizer inputs: Di-ammonium phosphate (DAP), goat manure and control. The split-split plots comprised of maize and beans cropping systems. Soil moisture content was assessed at 4, 8, 12 and 16 weeks after emergence, whilst nutrient uptake, use efficiency and crop yields at physiological maturity. Data was subjected to analysis of variance. Results: Soil moisture, maize and beans yields, nutrient uptake and use efficiency were significantly (p ≤ 0.05) increased by in-situ water harvesting technologies and fertilizer inputs. Highest soil moisture content was recorded under zai and ngolo pits and lowest in conventional tillage treatments. Ngolo pits recorded higher maize and beans grain yield. Application of DAP fertilizer increased maize and beans grain yield compared to control. Intercropping maize and beans increased grain yield significantly (p ≤ 0.05) compared to sole maize and sole beans. Implications. There is need for promoting a combination of in-situ rainwater harvesting technologies especially ngolo and zai pits with application of DAP+ manure in semi-arid areas where water is scarce coupled with poor soil fertility. Conclusion: Ngolo and zai pits increased soil water retention capacity while application of DAP fertilizer led to increased crop yield and the study therefore recommends their adoption within the study area and extrapolation to areas of similar conditions. 
      PubDate: 2022-08-15
      DOI: 10.56369/tsaes.4247
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Albaluz Ramos Franco
      Abstract: Background. State investments to improve the quality and quantity of water for human consumption require cost-effectiveness, especially in the Latin American and Colombian socioeconomic context. The conceptual framework of water ecosystem services allows decision makers to prioritize areas where monetary resources do generate a real impact on the water supplied to municipal aqueducts. Objective. Determine the areas and activities that should be invested as a priority, to promote two water ES in four municipalities of Boyacá. Methodology. The software RIOS was used in order to generate geographical explicit scenarios to indicate the areas where the municipal government must implement activities that in the short, medium and long term, will guarantee a baseflow at the dry season and the decrease of sediments by erosion. Results. It was identified that the higher altitude wooded areas in the basin, should be the object of agroforestry programs in its multiple expressions. Implications. In the specific case of Togüi, agroforestry does not seem to be the activity that contributes to flow control, possibly because of the natural slopes of the basin. Conclusion. This information can be used as a basis for the development of payment for water ecosystem services schemes (PWS).
      PubDate: 2022-08-15
      DOI: 10.56369/tsaes.4260
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Christian Szambelam Zimmermann, Ivan Ricardo Carvalho, Murilo Vieira Loro, Aline Luiza Schmidt, Helaine Claire Ferreira de Almeida
      Abstract: Background. The management of diseases in soybean crops demands a great economic cost with fungicide applications. Therefore, unnecessary or excessive applications can promote negative environmental results. Therefore, understanding the weather conditions and the development of diseases in the crop is essential to avoid the unnecessary use of fungicides, consequently reducing costs and ensuring the sustainability of the activity. Aim. The aim is to identify which yield components are quantitatively affected, and which aspects of the chemical composition of the grains are qualitatively influenced by fungicide management, in addition to relating the cost-benefit rate of sequential applications or previously stipulated management in the soybean crop, as well as their economic effects under water deficit conditions. Methodology. The trial was carried out using a randomized block design composed of 4 replications. The trial consisted of 5 kinds of fungicide management, defined by the time and number of applications, during the development cycle of the Lança cultivar, in the 2019/2020 crop season. Soybean agronomic traits and nutritional attributes were evaluated. Results. Unfavorable climate conditions contributed to the low rate of Asian rust infection during the soybean development cycle. The different kinds of fungicide management influenced soybean performance for the main agronomic variables studied. For the chemical composition of the grains, there was no statistical difference in relation to the different kinds of fungicide management. Implications. The results indicate that the management of fungicides must be carried out according to the meteorological conditions of the year of cultivation. Conclusion. Management without fungicide application maximized grain yield and promoted the highest economic return.
      PubDate: 2022-08-15
      DOI: 10.56369/tsaes.4262
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Mirian Irene Capa-Morocho, Adriana Romero-Maza, Melissa Romero, Marlene Molina-Müller, Santiago C Vásquez, Johnny Fernando Granja
      Abstract: Background. In the new global economy, cocoa is an important crop. However, far too little attention has been paid to the nutritional aspects. On the other hand, nitrogen is the most important nutrient in crop production, and mineral nitrogen fertilizers are the most widely used by farmers. Improving the efficiency of nitrogen uptake and utilization could potentially increase crop yields and quality, as well as reduce nitrogen fertilization and environmental pollution. Objective. Therefore, the objective of this study was to evaluate the effect of three nitrogen sources on morphological characteristics, yield and quality of CCN-51 cocoa, and soil chemical characteristics in the Ecuadorian Amazon. Methodology. A randomized design was established with 4 treatments with the same N dose, but varying the source (amide: urea, calcium nitrate, NC, and ammonium sulfate, SA), plus a control without N application. The investigated variables are soil chemical characteristics, shoot growth, fruit morphology, seed chemical characteristics, production and yield estimates, and agronomic efficiency of the sources. Results. NC maintained soil pH at 5.29 points compared to SA and urea, which acidified at a higher rate (4.32 and 3.96), leading to an increase of N and a decrease Ca in the soil. SA increased the fat content in the cocoa seed (54.1 %), with a higher number of fruits per plant (16.7) and, therefore, a better yield (0.799 t/ha). Implications. These results provide basic information on the nitrogen source effects and cocoa nutrition to be considered for future research. Conclusion. The findings suggested that NC conserves soil pH better than the other sources. SA increases production and fat content, so it can be considered the most efficient. 
      PubDate: 2022-08-15
      DOI: 10.56369/tsaes.4316
      Issue No: Vol. 25, No. 3 (2022)
  • IN VIVO CONTROL OF Phaeoacremonium parasiticum WITH NATIVE ANTAGONISTS
           Bacillus, Trichoderma AND actinomycetes AND THEIR GROWTH PROMOTING EFFECT
           IN GRAPEVINE

    • Authors: Davies Arturo Morales Pizarro, Javier Javier Alva, Luis Armando Álvarez, Ricardo Peña Castillo, Roger Chanduví García, Carlos Granda Wong, Rocío Mayta Obos, David Lindo Seminario, Sandro Condori Pacsi
      Abstract: Background: Phaeoacremonium parasiticum is a frequently species associated with "Petri's disease" in young plants of grapevine in Peru. One of the main limitations is the use of fungicides and the limited molecules for its control. In this scenario, biological control is an important alternative to integrate in the management of grapevine diseases. Objective: The objective of the research was to evaluate the in vivo efficacy of native antagonists to P. parasiticum and their growth promoting effect on grapevine. Methodology: Plant material from mother plants (R-110) underwent thermotherapy (52.5°C for 30 min). Subsequently, the antagonists (bacteria and fungi) were inoculated by partial immersion at a concentration of 1x106 cfu ml-1 (Colony forming units) for 3 h; 30 days later, P. parasiticum was inoculated, measuring shoot length before inoculation (SLBI). Seventy days after inoculation (DAI), shoot length (SL), length of necrotic stria (LNS), root dry weight (RDW) and root fresh weight (RFW) were measured. Results: Isolate Tr-5 (Trichoderma spp.) increased SLBI by 68%. Bacillus spp. (Bac-1, Bac-2), Trichoderma spp. (Tr-5) and T. harzianum (T-22) increase >40% SL 70 DDI. Tr-6 (Trichoderma spp.), T-22 and Act-2 (Actinomycete) reduce >50% LNS. Bacillus spp. (Bac-2: Bac-3) significantly increase RFW (59.29%: 49.39%) and RDW (60.41%: 55.08%). Implications: Biological control with native antagonists reduces the development of Petri disease and promotes grapevine growth. Conclusions: The native antagonists show growth-promoting effect and control of LEN caused by P. parasiticum at the nursery stage.
      PubDate: 2022-08-15
      DOI: 10.56369/tsaes.4232
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Oswaldo Guzmán López, María del Carmen Nuñez-Camargo, Alejandro Salinas-Castro
      Abstract: Background. Cultivation of forage grasses is an important component in the dual-purpose cattle production system; however, insect pests can decrease fresh material yields. Objective. To taxonomically identify the causal agent that damages the cultivars Panicum maximum (Jacq.) cv. Mombasa and Panicum maximum cv. Zuri. Methodology. In two locations in the central region of Veracruz, specimens of an insect in the larval and pupal stages were collected using the quadrant method in an area of 50 ha. Subsequently, in the laboratory, larvae were boiled for two minutes and preserved in 70% alcohol. Meanwhile, pupae were placed in a brood chamber with foliage to obtain adults and to extract their genitalia, which represents the most important morphological structure for the identification of a species. Results. The total number of collected larvae was 650, and 65 pupae, all reaching the adult stage. Based on the taxonomic morphology, the species Mocis latipes or striped grassworm was determined. Damage was estimated at approximately 40% per hectare. Implications. Correct identification of the pest insect allows the implementation of a strategy for proper management. Conclusion. The species M. latipes was identified in forage grasses P. maximum cv. Mombasa and P. maximum cv. Zuri in Veracruz.
      PubDate: 2022-08-15
      DOI: 10.56369/tsaes.4282
      Issue No: Vol. 25, No. 3 (2022)
           REVIEW 1962 – 2019

    • Authors: Richard Zapata Salas, José F. Guarín, Leonardo A. Ríos Osorio
      Abstract: Background: Dairy industry economics and public health are negatively impacted when udder health is compromised. Intramammary infection is the most important infectious problem generating economic losses to the milk production systems around the world. Affectations of animal generated diseases on public health are well known. Several categories of analysis have been studied to implement prevention and control strategies against intramammary disease. However, the control of these affectations has been considered a complex problem based on various factors. Objective: characterize the categories and subcategories of analysis used for the study of udder health published in research papers during the period comprehend between 1962 - 2019. Methodology: A systematic review with a broad approach in the research protocol was designed applying the identification phases, screening, choice, and inclusion criteria described in the PRISMA guide. A qualitative synthesis of year of publication, continent, focus, category of udder health analysis, and subcategories of udder health analysis was performed. Results: We found that more than half of the papers identified in this topic were published in the last decade of the studied period (1962 - 2019). New categories were incorporated into the timeline, evidencing an evolution in the way of understanding udder health problems. Implications: Many of the countries that publish most of the papers have implemented programs and policies on udder health management in recent years. Precisely in the last decade, cultural processes and political processes were incorporated into the study of udder health. This incorporation of new and relevant topics may have been very useful in the design and evaluation of public policies on udder health in those countries. Conclusions: These results show the interest in the academic, productive, and political sectors for udder health and its consequences on public health.
      PubDate: 2022-07-12
      DOI: 10.56369/tsaes.4168
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: David Hernández-Sánchez, Saraí Rico-López, Paulino Sánchez-Santillán, Marco Antonio Ayala-Monter, María Magdalena Crosby-Galván, Serafín Jacobo López-Garrido
      Abstract: Background. Prebiotics stimulate the growth and activity of the beneficial microbiota of the digestive tract, improve the health of the host and act as growth promoters. Inulin has prebiotic potential in ruminants, acts as an immunomodulator, improves intestinal health and productive behavior. However, its prebiotic effect on the ruminal microbiota is still unclear, given the little research carried out to date. Objective. This review focuses on the prebiotic effect of inulin and the benefits on the health and productive behavior of ruminants. Methodology. The bibliographic search was carried out in publications of international and national indexed journals, which have a strict peer review, written in English and Spanish, which included information related to inulin, its prebiotic effect, as well as the response of its use in health and ruminant performance. The scientific results of the reviewed articles were compared and contrasted. Main findings. The research analyzed demonstrate the potential use of inulin as a prebiotic in ruminants during lactation and weaning; benefits are shown on intestinal health and reduction in the incidence of diarrhea. In addition, improvements in animal behavior are observed. Inulin improves milk production in cattle. However, the little information available to date does not allow to determine the effect of this prebiotic on the ruminal microbiota. Implications. The information presented in this article shows that the effect of inulin as a prebiotic depends on its degree of polymerization, the age or growth stage of the ruminant, the doses used and, where appropriate, the probiotic population involved. Conclusions. The use of inulin as a prebiotic enhances the probiotic activity of beneficial bacteria, improving intestinal health and ruminant’s performance. However, more research is required on the effect of inulin in the rumen to know its prebiotic potential on the ruminal microbial.
      PubDate: 2022-07-12
      DOI: 10.56369/tsaes.4122
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Eufracia del R. Salazar-Cuytun, Gabriel Enrique Pool-Yanez, Rodrigo Portillo-Salgado, Gamaliel Antonio-Molina, Ricardo A. Garcia-Herrera, Enrique Camacho-Perez, Claudia V Zaragoza-Vera, Einar Vargas-Bello-Perez, Alfonso Juventino Chay Canul
      Abstract: Background. The empty body weight (EBW) represents exactly the animal mass and is used as a base to calculate most of the nutrient requirements in most feeding systems. Objective. To evaluate models for estimating EBW in growing hair sheep in a feedlot system under tropical conditions. Methodology. One hundred fifteen male growing hair sheep lambs (Pelibuey, Black Belly, and Katahdin) between four to ten months of age with a mean shrunk body weight (SBW) of 34.50 ± 7.40 kg (± SD) were used. The relationship between SBW and EBW was assessed by means of three models: Eq. 1. Linear with intercept; Eq. 2.- Linear without intercept and Eq. 3.- Allometric. The predictive ability of models was evaluated by cross-validation. Results. The correlation coefficient among SBW and EBW was high (r = 0.98). The regression equations had high determination coefficients (r2) of 0.97. Based on the evaluations Eq.1 had the performance compared with other models. The following final model was fitted to estimate the EBW as a function of SBW of growing castrated male hair sheep: EBW (kg): -2.39 (± 0.53***) + 0.95(± 0.02***) × SBW (kg). Implications. These results contribute to the development of mathematical models for more accurate weight adjustments in growing hair sheep in a feedlot system under tropical conditions. Conclusion. The equation developed and evaluated in the present study revealed that the linear relationship between SBW and EBW can be used to predict EBW in hair sheep, for that the use of this model can be safely applied to male hair sheep. In addition, it was found that the relation BW/EBW was on average 1.18 for males. 
      PubDate: 2022-07-12
      DOI: 10.56369/tsaes.4213
      Issue No: Vol. 25, No. 3 (2022)
           palmarum L. IN A MEXICAN Cocos nucifera L. ORCHARD

    • Authors: Jesús Germán De La Mora Castañeda, Ingrid Yolotzin López Mora, Wilberth Chan Cupul, José Manuel Palma García
      Abstract: Background. Rhynchophorus palmarum is the main insect pest in Cocos nucifera orchards in the Pacific Centre of Mexico. The mass capture of adults is the strategy for control of this pest promoted by integrated pest management programs. It is essential to find an economic and efficient trap for farmers. Objective. The present study aimed to determine the efficacy and cost efficiency of five traps for capturing R. palmarum in a C. nucifera orchard and to correlate the capture with environmental parameters. Methodology. The bucket-trap (BT), trash-can trap (TCT), 20L-type trap (20LTT), bottle-type trap (BTT), and CSAT-type (Colegio Superior de Agricultura Tropical, a Spanish acronym) trap were evaluated. Total captured insects, number of males and females, cost of trapping, and cost-efficiency were measured. Total captured insects and environmental parameters were correlated using a Pearson model. Results. A total of 1065 insects were captured (60% females and 40% males). The TCT captured more (P=0.00001) insects than the BT, 20LTT and BTT. The CSAT ($540.5 USD) and TCT ($531.0 USD) were the most expensive traps during the period of the experiment (4.5 months), whereas the BTT was the cheapest ($515.5 USD). The cost of capture per insect in the TCT was $1.5 USD; therefore, this trap had the best cost efficiency overall of the studied traps (BT=2.6 USD, 20LTT=3.1 USD, CSAT=1.9 USD, and BTT=6.9 USD). The average (r=0.6115, P=0.0154) and maximum (r=0.6280, P=0.0122) wind speeds were correlated positively with the R. palmarum capture. Implications. This study demonstrates statistically that the TCT capture the same number of insects than the CSAT trap with lower cost. Conclusion. More females were caught than males, the TCT trap statistically captures the same amount of insects than the CSAT trap at a lower cost. Wind speed was positively correlated in the capture of R. palmarum. 
      PubDate: 2022-07-12
      DOI: 10.56369/tsaes.3933
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Sergio Segundo González Muñoz, Ignacio Arturo Domínguez Vara, José Luis Bórquez Gastelum, Juan Manuel Pinos Rodríguez, Jacinto Efrén Ramírez Bribiesca, Daniel Trujillo Gutiérrez
      Abstract: Background: The use of silages from non-conventional sources of nitrogen and soluble carbohydrates in feeding lambs is controversial in terms of nutrient supply; due to the minimum number of studies reported to date of in vitro evaluations that allow measuring its nutritional value in ruminants. Objective: To evaluate the additive effect and fermentation potential of silages plus concentrates in diets for lambs on the in vitro gas production kinetics. Methodology: Six diets (silage + concentrate) were evaluated in a factorial arrangement of 3 N sources (dried poultry litter, fresh swine manure, agricultural urea) × 2 carbohydrate sources (sugar cane molasses, bakery by-product). The diets contained: a) silage (400 g/kg DM) and b) concentrates (600 g/kg DM) based on soybean meal, ground corn, wheat bran, corn stover, fish meal, and vitamin and mineral premix. Average gas production data were analyzed with PROC MIXED and the gas production curves were fitted into the Exponential Logistic model with PROC NLMIXED. Results: The PO+MC (151.87 mL/gas MS) and CF+MC (153.12 mL/gas MS) treatments had higher average gas production during incubation. An additive effect was observed on the maximum asymptote of gas production in the CF+MC (+ 4.26%) and PO+MC (+ 3.75%) diets (P<0.01). Diets based on PO or CF combined with MC and SPP had higher IVDMD, IVOMD, and IVNDFD than the control treatment (UR). Implications: The inclusion in diets for growing lambs of corn stover silage based on rapidly fermentable carbohydrate sources with non-protein nitrogen from pig and poultry excreta in diets for growing lambs has associative effects on nutrient degradability and its fermentation potential in small ruminant feed. Conclusions: The PO+MC treatment has a higher potential for gas production due to the associative effect of its components. 
      PubDate: 2022-07-12
      DOI: 10.56369/tsaes.3938
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Evert Villanueva-Sánchez, Samuel Ramírez-Alarcón, Clemente Villanueva-Verduzco, José Enrique Herbert-Pucheta
      Abstract: Background. Entomopathogenic nematodes (NEP) are found in all ecosystems. Currently, they are one of the most studied ecological alternatives for the biological control of insect pests. In Mexico, there are few reports of their presence in agricultural soils. Objective. To isolate and identify molecularly native specimens of entomopathogenic nematodes from soil samples collected in different prickly pear producing areas in Milpa Alta, Mexico City. Methodology. Isolations were obtained from soil samples using the technique of insect lure (Galleria mellonella or greater wax moth). Molecular techniques of the ribosomal region (ITS1+5.8S+ITS2) were performed for nematode identification. Results. Of the NEP isolates for the genus Steinernema, the phylogenetic analysis (ML; HKY) grouped the sequences of the isolates in the species Steinernema texanum, with 100 % similarity and 81 % similarity between isolates. For Heterorhabditis, the analysis (M; HKY) grouped the sequenced isolates in the species Heterorhabditis atacamensis with 97 % similarity. The results show that the NEP are widely distributed in the study region. Implications. The presence of these isolates in the cultivation of prickly pear (nopalitos) is important since they are a potential biological tool for pest management in the study zone. Conclusion. For the first time, the presence of Steinernema texanum and Heterorhabditis atacamensis is reported in soils cultivated with prickly pear in Milpa Alta, Mexico.
      PubDate: 2022-07-12
      DOI: 10.56369/tsaes.4123
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: David Hernández-Sánchez, Jerónimo Herrera-Pérez, Serafín Jacobo López Garrido, Nicolás Torres-Salado, Paulino Sánchez-Santillán
      Abstract: Background. Cellulolytic bacterial consortia (CBC) serve as additives to improve fiber degradation in ruminants, since they improve biogas production and in vitro fermentation characteristics. Objective. To evaluate the biogas production and fermentative characteristics in vitro of mulato grass inoculated with ruminal CBC obtained from ground sawdust, ground mulato grass or whole stem as substrates in the selective culture medium. Methodology. The CBC were obtained from ruminal fluid from a Suiz-Bu cow fitted with a ruminal cannula, which was transferred six times in a selective anaerobic medium. The test consisted of preparing sterile biodigesters with 0.5 g of mulatto grass with 63 d of regrowth, 45 mL of culture medium. The inoculation was with 5 mL of a type of CBC. The biodigesters were incubated 72 h at 39 °C. Biogas production was measured at 3, 6, 9, 12, 24, 48 and 72 h. In the culture media, ammonia nitrogen (N-NH3), total bacterial count, cellulase activity, pH, dry matter degradation (DMD) and neutral detergent fiber degradation (NDFD) were determined at 12, 24, 48 y 72 h. In the biogas production a completely random design was used; while in the rest of the variables a completely randomized design was carried out with a 3x4 factorial arrangement, with fiber source and incubation time as factors. Results. The biogas production of the CBC obtained from the ground grass showed higher (p<0.05) accumulated production in all the evaluated times. The CBC obtained from sawdust increased the biogas production by 175% from 24 to 48 h and by 313% from 48 to 72 h. There was an interaction effect (p <0.05) on DMD, NDFD, N-NH3, total bacterial count and cellulase enzymatic activity. The CBC obtained from ground mulatto grass at 72 h increased (p <0.05) the DMD and NDFD. The CBC obtained from sawdust increased DMD by 19.1% and NDFD by 33% from 48 to 72 h. The concentration of bacteria in the observed interactions is within the range of the ruminal ecosystem. The highest (p<0.05) content of N-NH3 was determined when the CBC obtained from grass stem with 12, 24 and 72 h of incubation were used. Implications. Using the same fiber source to obtain the CBCs improves the degradation of said fiber. Conclusion. The size and source of fiber are decisive in the type of bacteria that make up the cellulolytic bacterial consortia of ruminal origin under the conditions of this in vitro test.
      PubDate: 2022-07-12
      DOI: 10.56369/tsaes.4127
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Teresa Romero Cortes, Victor Hugo Pérez España, Martin Peralta Gil, José Esteban Aparicio Burgos, Jaime Alioscha Cuervo Parra
      Abstract: Background. Wild teosintle populations represent an important source for the increase of the genetic variability of the native corn of Mexico and Central America. Teosintle plants have a great tolerance to climatic variation and grow in a wide range of altitude; despite this, it is a plant genetic resource that is scarcely valued and therefore little studied. Objective. Morphologically characterize and make a phenological evaluation of accessions of Mexican wild teosintle from CIMMYT. Methodology. An experimental design of complete random blocks with three repetitions and plots of 4 rows of 2 m long with a separation between rows of 80 cm and a planting density adjusted to a hectare of 15,000 plants was used. Results. The Chalco and Mesa Central races of Zea mays ssp. mexicana were those that demonstrated the best values for the agronomic performance variables studied amongst of all the teosintle treatments evaluated. Implications. With the knowledge generated, it will be possible to establish management strategies for wild teosintle populations for commercial purposes. Conclusion. Based on the results obtained, the Chalco and Mesa Central races could be considered to increase genetic variability in genetic improvement programs of commercial corn, as food for farm animals and/or humans and in plant germplasm conservation programs.
      PubDate: 2022-07-12
      DOI: 10.56369/tsaes.4147
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Ismael Quiroz Guerrero, Arturo Pérez Vázquez, Cesáreo Landeros Sánchez, Felipe Gallardo López, Joel Velasco Velasco, Griselda Benítez Badillo
      Abstract: Background. Climate change puts pressure on the agroecosystems, and the cultivation of Coffea arabica may not be resilient under these conditions. Objective. The objective of this study was to determine the impact of climate change on coffee agroecosystem resilience. Methodology. Maxent software was applied to model current and future scenarios. The current scenario was developed using 19 bioclimatic variables obtained from the Worldclim database with climate records for the period 1960-1990. As for the future scenario, the impact of climate change was modeled based on climate projections for the year 2050 using 3 different global climate models: CCCMA, HADCM3, and CSIRO. The variables in this study were analyzed using Statistica and Gephi software. Results. The results showed under the climate change scenario that 15% of the plots were distributed in unsuitable / non-resilient areas and 85% in moderately suitable and suitable/resilient areas for the establishment of C. arabica. Also, the adaptation indicators showed a higher frequency (30) of negative values in coffee agroecosystem (C-AES) plots in areas of both high impact and low impact. Implications. The data could allow the redesign of the coffee agroecosystems to improve the weak elements of its structure. Even the structure reinforcement could be direct with farmers or by public politics, government institutions, organizations, and coffee businessmen. Conclusion. It was concluded that after 2050, the conditions for coffee cultivation will be reduced and as a consequence, the proportion of plots at lower altitudes will remain outside the optimal environmental conditions. On the other hand, there will be plots within the area with suitable conditions for cultivating C. arabica, therefore these will be resilient to climate change, but these will need to establish precise adaptation strategies for the disturbances that will take place in the immediate future. 
      PubDate: 2022-07-12
      DOI: 10.56369/tsaes.4161
      Issue No: Vol. 25, No. 3 (2022)
  • GERMINATION AND MORPHOLOGICAL ASPECTS OF Echinocactus platyacanthus Link &

    • Authors: Oscar Martín Antúnez-Ocampo, Gerardo A. Castañeda-Zárate, Juan Elias Sabino-López, Mariana Espinosa-Rodríguez, Serafín Cruz-Izquierdo
      Abstract: Background. The sweet biznaga (Echinocactus platyacanthus) is endemic to Mexico, whose seeds show low germination, viability, longevity, genetics, and latency; therefore, gamma irradiation is an alternative to stimulate the emergence and growth of seedlings, by causing variations in the chemical composition of DNA, which causes cytological, biochemical, physiological and morphological changes in plants. Objective. The objective of the present investigation was to evaluate the effect of different doses of gamma 60Co radiation on seed germination and seedling vigor of E. platyacanthus. Methodology. E. platyacanthus seeds were irradiated at 0, 50, 100, 150, 200, 250, 300, 350, 400, 450, 500 and 550 Gy of 60Co gamma rays, then they were sown in transparent plastic containers covered with filter paper and were distributed in a completely randomized design with four repetitions in a germination chamber, the percentage of germination and survival of seedlings in the container was recorded 30 days after sowing (das). The seedlings were transplanted at 30 das into black polyethylene bags with tezontle and established in a completely randomized design with 12 treatments and four replications, in a tunnel-type greenhouse. At 20 and 30 days after transplantation (dat) seedling vigor was measured based on height (cm), stem diameter (mm) and root length (mm) and at 20 dat survival was recorded (%) of seedling in the substrate. An analysis of variance and Tukey's test for comparison of means (p ≤ 0.05) were performed. Results. Gamma irradiation stimulated seed germination from 10 to 29%. In seedlings, root height and length were modified with intermediate doses of gamma rays (100 to 200 Gy); but higher doses negatively affected these indicators. Survival of containerized M1 seedlings was up to 63% higher than the control, depending on the irradiation dose. Implications. Irradiation with 60Co gamma rays improves seed germination, survival and vigor of E. platyacanthus seedlings. Conclusions. Irradiation with 60Co gamma rays stimulated seed germination and improved some characteristics of vigor in E. platyacanthus seedlings, by modifying root height and length according to age. In addition, it increased the survival of containerized seedlings.
      PubDate: 2022-07-12
      DOI: 10.56369/tsaes.4235
      Issue No: Vol. 25, No. 3 (2022)
           sp) AND GRASSHOPPER (Sphenarium purpurascens) EXOSKELETONS

    • Authors: Adolfo Amador Mendoza, José Manuel Juárez Barrientos, Hipólito Hernández Hernández, Laura Patricia Ramírez Coutiño, Sergio Huerta Ochoa, Erasmo Herman Lara, Jesús Rodríguez Miranda
      Abstract: Background. Chitin is found in high concentration in insects, this being a new source of exploitation, due to the similarity in the content of chitin in exoskeletons of crustaceans compared to insects, especially those considered pests. Objective. Evaluate and compare the biological process of solid medium fermentation (SMF) combined with three treatments: ultrasonication, chemical and enzymatic hydrolysis in the purification of chitin from shrimp (Penaeus sp) and grasshopper (Sphenarium purpurascens) exoskeletons. Methodology. It consisted of the implementation of a pretreatment by fermentation in a solid medium (SMF) with chitinous samples (shrimp and grasshopper) combined with ultrasonication (20 kHz, 750 W, 120 min, 30 °C, 1/20 p/v), hydrolysis chemical (0.4 M NaOH, 0.6 N HCl, 38% NaClO, 1/15 p/v, 25 °C, 4 h) and enzymatic (Alcalase® 2.4L, 1:2 E:S, pH 7.5, 70 °C, 150 rpm, 300 min). Results. The combined treatments of SMF-ultrasonication, SMF-chemical hydrolysis, and SMF-enzymatic hydrolysis showed a higher percentage of deproteinization (84.82, 94.67, and 80.45%) and demineralization (82.12, 95.58, and 52%) with shrimp exoskeletons compared to shrimp exoskeletons grasshopper percentages (76.38, 92.04 and 78.71%) and (79.39, 95.37 and 51.79%) respectively. Implications. The chemical treatment generated greater protein and mineral removal compared to the other treatments, reaching yields of 54.45% in shrimp and 51.88% in grasshoppers. Conclusion. Ultrasonic waves extracted chitin in a shorter time (2h) with yields of 74.43% in shrimp and 78.02% in grasshoppers, reducing the amount of water.
      PubDate: 2022-07-12
      DOI: 10.56369/tsaes.4240
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Raúl Allende-Molar, Karla Marina Báez-Parra, Edith Salazar-Villa, Indira Rojo-Báez
      Abstract: Background. Trichoderma is a cosmopolitan genus of fungi with beneficial species that help both to improve the plant rhizosphere and combat pathogens in economically important crops. Due to its importance in the agricultural biotechnological field, the morphological and molecular identification of Trichoderma species is of interest; however, currently the information on identification, biocontrol and its applications in agriculture is scattered. Objective. The objective of this review was to carry out an exhaustive analysis on the identification of Trichoderma, as well as an analysis of biocontrol studies and applications of Trichoderma in agriculture in Mexico. Methodology. A bibliographic review of Trichoderma was carried out in the following databases: Scopus, Science Direct, NCBI, Google Scholar, Pubmed and USDA. The keywords used were Trichoderma, identification, morphology, molecular, antagonism, biocontrol, agricultural use, agricultural importance, and Mexico. The collection of information on Trichoderma species in Mexico was considered during the period from 2005 to 2022. Results. In Mexico, 42 species reported to date of Trichoderma based on morphological characteristics were found, the main identified species are T. harzianum, T. asperellum and T. viride; according to the ITS barcoding marker and tef1α gene region, 17 species reported to date have been identified at the molecular level. The main species reported are T. asperellum and T. harzianum. Additionally, the most reported species as antagonists are T. asperellum and T. harzianum, the latter being the one that is mostly marketed in biological products. Implications. Currently the species T. asperellum and T. harzianum stand out in identification, biocontrol, and application in agriculture. Conclusions. Morphological identification alone is difficult; recently in Mexico, the identification of Trichoderma species is carried out at an exhaustive level, complementing the morphological identification with molecular identification. At present, reports on the diversity of Trichoderma species have increased in identification, biocontrol, and applications in the agricultural area.
      PubDate: 2022-07-01
      DOI: 10.56369/tsaes.4297
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Jeferson Asprilla-Perea, Yirson Romaña-Romaña
      Abstract: Background. The Afro-descendant communities inhabiting the lower portion of the Atrato River basin in Colombia maintain a close relationship with their environment's biological diversity and ecosystem. Although the wild birds in the basin have been studied for their richness and ecological value, there are no ethnobiological accounts, even though this resource has been traditionally used in these communities’ feeding. Even though most of such communities consist of fishers, farmer families, and wood merchants, they have a solid vocation for occasional hunting since the performance of their regular activities requires that they carry tools such as a shotgun for hunting the wild birds and mammals they come across in passing through the jungle or near a swamp. Objective. Know the traditional use of meat and wild bird by-products by two Afro-descendant communities in the lower basin of the Atrato River in northwestern Colombia. Methodology. Interviews were conducted with 21 key informants (local experts) as well as 173 household surveys. Mann-Whitney end Kruskal Wallis tests were performed to determine statistically significant differences using the R Software 4.1.2 and RStudio 1.4.1103 programs. Results. Wild bird diversity in the tropical rainforest provides a wide range of meat products for food security of the Afro-descendant communities that inhabit the lower portion of the Atrato River basin in Colombia. This assortment consists of at least 20 species, Galliformes foremost. Meat and viscera are generally consumed through preparations such as sancocho, stewed meat, fried meat, smoked meat, roasted meat, ground meat, or shredded meat, and no disease or discomfort for human health have thus far been associated with its consumption. Wild birds are consumed in all the households that were surveyed, and the most important for these communities are Cairina moschata sylvestris (mountain duck), Penelope ortoni (dusky-legged guan), Dendrocygna autumnalis (black-bellied whistling duck), Chauna chavaria (northern screamer), Colinus cristatus (crested bobwhite), Phalacrocorax brasilianus (crow duck) and Ortalis cinereiceps (little ground tyrant). Comparisons between the two communities showed that this resource becomes more critical the more isolated the territory. Implications. This study is an input to understand the importance of wild biological diversity for family feeding in human communities in tropical zones. Conclusions. The seven species indicated above constitute the basis for prioritizing wild birds for bioprospecting purposes in planning food and nutritional security for these communities, which also requires that the parties involved in biodiversity conservation pay particular attention to certain species being used for food.
      PubDate: 2022-06-30
      DOI: 10.56369/tsaes.4223
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Natã Balssan Moura, Ivan Ricardo Carvalho, Kassiana Kehl, Leonardo Cesar Pradebon, Murilo Vieira Loro, Eduarda Donadel Port, Inaê Carolina Sfalcin, José Antonio Gonzalez da Silva, Adriano Udich Bester
      Abstract: Background. Wheat is a staple food crop and easily accessible to the population, so the biofortification of wheat grains is substantial to mitigate malnutrition. Objective. To evidence and select wheat genotypes based on nutritional multi-characters of grains based on genetic parameters. Methodology. Experiments were carried out in the 2019 agricultural season in five wheat areas of the state of Rio Grande do Sul, in two sowing seasons, in the municipalities of Cachoeira do Sul, Cruz Alta, Santo Augusto, São Gabriel and Vacaria. The experimental design was randomized blocks, organized in a factorial scheme with 10 cultivation environments (5 sites by two sowing dates) and 30 genotypes, with three replications. To carry out the selection of genotypes, the WAASB, AMMI, GGE and BLUP methodologies were applied. Results. In terms of lipids and fibers, three mega environments were formed, highlighting the genotypes BRS 327, CD 1550, Ametista, CD 1303 and BRS 331, respectively. For mineral material, there was the formation of two mega environments and the genotypes that stood out were Quartz and Tbio Toruk, while for carbohydrate there was the formation of a mega environment and the genotype that stood out was CD 1550. The Tbio Mestre and LG Prisma genotypes were the ideal genotypes, with high performance in the Cachoeira do Sul environment – Sowing 2nd fortnight. Tbio Iguaçú expressed high levels of lipids in Santo Augusto – Seeding 1st fortnight, São Gabriel – Seeding 2nd fortnight and Vacaria – Seeding 2nd fortnight. ORS 1405 and Tbio Iguaçú expressed high levels of carbohydrates in the Vacaria - Seeding 2nd fortnight environment. Heritabilities without interaction effects were high, which characterizes high genotypic additive variance. Implications. The current results indicate that there is genetic variability, making it possible to select genotypes with greater expression of nutrients in the grains. Conclusion. The TBio Mestre, CD 1440, LG Prisma and Marfim genotypes expressed greater performance and stability of the evaluated traits.
      PubDate: 2022-06-30
      DOI: 10.56369/tsaes.4244
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Yuliana Izquierdo-Camacho, José Candelario Segura-Correa, Nadia Florencia Ojeda-Robertos, Alfonso Juventino Chay-Canul, Víctor Hugo Severino-Lendechy, Jorge Alonso Peralta Torres
      Abstract: Background. The resumption of ovarian activity after parturition is related to reproductive efficiency. Objective. To determine the effect of breed group and some non-genetic factor on resumption of ovarian activity and pregnancy rate of dual-purpose cows. Methodology. In study 1, 37 cows were sampled biweekly, from the day 15 to 150 postpartum or until a corpus luteum (CL) was detected. Follicular population (FP), maximum follicle diameter (MFD) and maximum CL diameter (MCLD) were also measured. In study 2, 71 cows were pregnancy diagnosed. Chi2 tests and analyses of variance were performed to determine the effects of breed group, parity number, body condition score (BCS), BCS change (BCSC) and body weight change (BWC) on the dependent variables. Results. In study 1, aproximately, 84% of cows resumed ovarian activity at 68.3 days. More CL were found in multiparous cows (92.59%) and those with BCS ≥3.0 (95.83%). No differences were found in the FP and MFD. F1 cows had the largest MCLD (19.51 mm). In study 2, pregnancy rate was higher in cows with 2-3 (47.83%) and ≥4 parities (54.55%), F1 (54.29%) cows, those gaining BCS (64.29%) and high body weight (66.67%). Implications. Results suggest that primiparous cows and those with BCS ≤2.5 require better management; therefore, strategies must be established to improve reproductive efficiency. Conclusion. Primiparous and cows with BCS ≤2.5 delayed the first ovulation. Multiparous, F1 cows, those gaining BCS and body weight after calving had the highest pregnancy rate. 
      PubDate: 2022-06-30
      DOI: 10.56369/tsaes.4249
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Francisco Bautista, Yameli Aguilar, Neftaly Gijón
      Abstract: Introduction: The state of Yucatán is the third national producer of pork meat due to a large number of pig farms, there are them of all sizes from very small to mega-farms with more than 30 000 pigs, many of which generate environmental and social problems. Objectives: The analysis of the operation of pig farms in Yucatán; identification of environmental problems; and proposals for mitigating damage to the environment and human health. Results: The environmental problem is generated by the large amount of water with which they operate to clean the farms and cool the pigs during high-temperature days. In addition to the large volumes of water extraction, large volumes of wastewater are generated that are not properly treated and that contaminate air, soil, and groundwater. In this work, the traditional way of operating farms is documented, emphasizing environmental damage. The particularities of karst landscapes and their environmental vulnerability are explained. Implications: Ways of reducing environmental problems are proposed with the idea that they are taken into account to move towards sustainable management of pig farms in the state of Yucatán, for example, selection of the best sites for pig farming (relief, soils, climate, and depth of groundwater), reduction of extracted water, treatment through artificial wetlands and agricultural use of wastewater through sprinklers in soils of the Luvisol, Nitisol and Vertisol groups. Conclusions: For the transit of contamination to Sustainability in the management of pig farms in the state of Yucatán requires knowledge, innovations to solve problems, social commitment with local communities, and environmental regulations. It will not be easy but it is possible.
      PubDate: 2022-06-28
      DOI: 10.56369/tsaes.4154
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Dereje Andualem, Melaku Hundessa
      Abstract: Background: Gedeo agroforestry is characterized as the integration of trees, crops and livestock on the same unit of land. Land scarcity is a common characteristic in the Gedeo agroforestry system.  Hence integrating forage crops with the agroforestry system is one of the options to alleviate feed scarcity in the area. Objectives: To evaluate the biomass yield and nutritional value of Guatemala grass harvested at three stages of maturity: Early (120days), Mid (150days) and Late (180 days) cultivated at three different altitudes (high, medium and low). Methodology: A randomized complete block design with three replications was employed. Morphological parameters and chemical composition were measured at each stage of maturity and altitude. Result:  The results showed that the number of leaves per plant (NL), plant height (PH), leaf length (LL) and dry matter yield (DMY) exhibited (p<0.05) an increasing trend as harvesting days were delayed. Contrarily the number of tillers (NT) showed (p<0.05) decreasing trend as harvesting dates advanced. The highest (p<0.05) CP (12.6±0.25%DM) was recorded at 120 days. The highest (p<0.05) NDF (61.27±0.07%DM) and ADF (42.3±0.91%DM) were recorded at 180 days of harvesting. The highest (p<0.05) IVDMD (56.7±1.97%) was recorded at 120 days of harvesting, whereas the least (p<0.05) (48.0±2.06) was at 180 days of harvesting. Generally, as the harvesting date advanced, CP and IVDMD showed a decreasing trend, whereas the fiber content (ADF, NDF and ADL) showed an increasing trend. Implication: Based on the morphological characteristics and dry matter yield, the best harvesting stage of Guatemala grass was at the late (180days) stage of maturity. On the other hand, considering the chemical composition and IVDMD, the best harvest stage was at the early (120days) stage of maturity. Conclusion: Cutting Guatemala grass at the proper growth stage is crucial for forage management.  However, to fully utilize the potential of Guatemala grass, further studies on live animal experiments should be carried out.
      PubDate: 2022-06-28
      DOI: 10.56369/tsaes.3685
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Laura Rodríguez-Bustos, Leopoldo Galicia, Bruno Chavez-Vergara, Ofelia Beltrán-Paz
      Abstract: Background. Soil ecological functions such as C mineralization, enzyme activity, and microbial biomass determine the maintenance of soil fertility in the short and long term. Microbial activity is a sensitive indicator of changes in soils under agricultural management. Objective. Evaluate the metabolic response of soil microbial communities in two temperate maize agroecosystems with different management intensities. Methodology. This study evaluated total soil nutrient concentrations, C mineralization, and microbial metabolic activity by comparing two agricultural regimes. The first one is an intensive regime (IR) characterized by the exclusive use of synthetic fertilizers in a maize monoculture. The second one is a traditional regime (TR) characterized by the use of mixtures of organic matter (maize and bean residues and manure) with synthetic fertilizers in a rotation system of maize and beans. Physical, chemical, and biological properties were tested in the laboratory, and the specific enzyme activity (SEA) and metabolic quotient (qCO2) were calculated. Results. Total soil C concentration was 19% higher in TR (26.6 mg g-1) than in IR (5.1 mg g-1); total C biomass was 30% higher in TR (279 mg C g-1) versus IR (83.9 mg C g-1), and potential C mineralization was 40% higher in TR (356 µg C g-1 d-1) than IR (214 µg C g-1 d-1); in contrast, SEA and qCO2 were lower in TR versus IR. These results support the hypothesis that the microbial community is more efficient under TR than IR because it produces extracellular and intracellular enzymes while growing in biomass. Implications. The present study provides new information about the effect of agricultural management on microbial activity, which is important for farmers not only in Mexico Highlands but also in any agricultural scenario exposed to changes in management practices. Conclusions. Assessment of biological soil properties is a sensitive indicator of changes in soil properties induced by management. Metabolic indices are suitable for the evaluation of ecological functions in cultivated soils.
      PubDate: 2022-06-28
      DOI: 10.56369/tsaes.3911
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Ricardo Borjas-Ventura, Noel Bello-Medina, Segundo Bello-Amez, Leonel Alvarado-Huaman, Diana Rabaza-Fernandez, Lourdes Tapia Y Figueroa, Viviana Castro-Cepero, Alberto Julca-Otiniano
      Abstract: Background. Cacao is an important source of income, especially for small farmers in developing countries. However, its commercialization, and consequently its production, is threatened by the high levels of cadmium (Cd+2) in grains. Objective. This work was carried out with the objective of determining the differentiated uptake of six cacao genotypes in San Ramón, central Peruvian jungle. Methodology. The treatments consisted of the combination of different doses Cd+2 (0, 50, 100 and 150 ppm) with the genotypes CCN-51, ICS-60, ICS-95, POUND-7 and VRAE-99. Results. The results indicate that POUND 7 absorbed a greater amount of Cd+2 concentrated mainly in the root, while CCN-51 concentrated it mainly in the aerial tissues. In VRAE-99, a significant drop in stem height and diameter was observed, especially at the 150 ppm dose. This genotype was shown to be more sensitive to this metal at high doses (150 ppm) and decreased its photosynthetic rate and its efficiency in the use of water, which was confirmed by the increase in the internal carbon content. Implications. In general, it was found that POUND-7 is a promising genotype that can potentially be used as a rootstock because it is capable of accumulating Cd+2 mainly in the roots. Conclusion. Although cacao is considered a Cd+2 accumulator plant, this heavy metal can negatively affect the physiology of the plant as in the case of VRAE-99. Further studies are suggested to better understand how Cd+2 affects cacao physiology.
      PubDate: 2022-06-28
      DOI: 10.56369/tsaes.4000
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Serafín Jacobo López-Garrido, Silvia Santos-Jerónimo, Edgar Iván Sánchez-Bernal, Mónica Marcela Galicia-Jiménez, Narciso Ysac Ávila-Serrano, Marco Antonio Camacho-Escobar, Paulino Sánchez-Santillán, David Hernández-Sánchez
      Abstract: Background. The saline stress of tropical soils affects the growth and nutritional composition of pastures, therefore the availability and quality of forage for livestock is affected. Salinity can reduce crude protein content and increase the neutral detergent fiber (NDF) ratio of grasses. This can decrease ruminal degradability, microbial populations, and alter the production of volatile fatty acids (VFA), which are the main source of energy for ruminants. On the other hand, an increase in NDF in pastures can increase the emission of methane (CH4). For this reason, it is necessary to generate sufficient information on the nutritional quality of pastures grown in saline soils and their ruminal fermentation patterns. Objective. Evaluate hybrid grasses of the genus Urochloa, Cayman and Cobra grown in five concentrations of salinity, to determine their effect during in vitro ruminal fermentation, on chemical composition, degradability, fermentation parameters, ruminal microorganisms, on the production of CH4 and CO2. Methodology. Five experimental treatments were evaluated: salinity levels for both pastures of 0, 2, 4, 6, 10 dS m-1 of NaCl. The chemical composition of the two experimental grasses was determined, and subsequently they were incubated in vitro in a culture medium for total bacteria with the addition of fresh ruminal fluid, to determine dry matter degradability (DIVMS), ruminal fermentation parameters, microbial populations, and biogas production. Results. Cayman grass presented higher (P<0.05) ash content and ether extract at CE ≥ 4 dS m-1; however, its crude protein content decreased. In Cobra grass there was also protein reduction at 10 dS m-1. In both DIVMS grasses, AGV and CH4 production were not affected by salinity, nor were there changes in the count of ruminal microorganisms. Implications. The results of the present study evaluate the effect of salinity on crude protein content and cell walls of Cayman and Cobra grasses grown under salinity stress. It was determined that salinity does not affect the degradability or ruminal fermentation patterns of the pastures studied. Conclusions. With a salinity level of 10 dS m-1, the protein of Cayman and Cobra grasses decreased 8.42% and 18.0%, respectively. The salinity levels studied do not affect IVDMD, microbial population, or CH4 production during in vitro ruminal fermentation of the evaluated species.
      PubDate: 2022-06-28
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Leonardo Beltran-Rodriguez, Facundo Sánchez Gutiérrez, Angel Sol-Sanchez, Ramiro Puc-Kauil, Jonathan Hernandez-Ramos, Vicente Florencio Vasquez-Cortez, Cesar Orlando Pozo-Santiago, Francisco Montoya-Reyes
      Abstract: Background. The mangrove forest is a mixture of tree and shrub species which inhabit the coastal areas of the tropics and subtropics, around estuaries and coastal lagoons, near the mouths of rivers, with another different capacities than the tolerance of salinity. Despite its ecological and social importance, it is one of the ecosystems most threatened by changes in land use and climatic variations. Objective. Evaluate the increase in total height and basal diameter in the dry and rainy period in Avicennia germinans L. seedlings, from the nursery and from natural regeneration. Methodology. In ten sampling units (SU) the total height (At), basal diameter (Db) and the survival rate (%) of the reforested individuals were recorded. In each SU, three Sub-SU (SSU) were installed where only the first two attributes were recorded for natural repopulation. The measurements were carried out in three stages during one year (M1, M2 and M3). Results. The mean annual increase in reforestation was 1.14 cm in Db and 58.8 cm in At. SU 4 was the one that reported the greatest increase in Db (1.87 cm) and At (132.6 cm), while the lowest values were presented in SU 9. The growth relationship between Db and At was statistically significant (p ≤ 0.05). Reforestation survival decreased from 73.2% to 52.7% during the evaluation period. The highest growth in Db, At and survival were in the SU´s where the water flow is greater and with a canopy gap is larger. Natural regeneration had a lower mean annual increase in both Db (0.51 cm) and At (37.2 cm). Implications. This novel information provides the basis for the planning, management and conservation of A. germinans in the southeast of Mexico. Conclusion. The time of measurement and the ecological differences between sampling units significantly influence the dasometric increase of A. germinans. The reforested individuals show a greater annual increase in Db and At compared to those of natural regeneration.
      PubDate: 2022-06-28
      DOI: 10.56369/tsaes.4132
      Issue No: Vol. 25, No. 3 (2022)

    • Authors: Caleb Wangira Mbayaki, George Njomo Karuku
      Abstract: Background: Soil hydraulic parameters in non-saturated conditions are crucial for explaining soil water dynamics in the field. It is therefore necessary to understand the link between soil water potential and hydraulic conductivity in the soil in order to estimate plant available water and hence simulate its movement within the soils. However, measurement of such hydraulic properties in the field and laboratory is somehow difficult, laborious and costly. Objective: To determine soil hydraulic properties of Ferro-chromic Luvisols in Katumani using the RETC code based on pedo-transfer functions; % sand, silt, clay and soil bulk density. Methodology: Undisturbed soil samples were collected from a profile pit at 0-15, 16-30, 31-45 and 46-60 cm depths using core rings for bulk densities and texture determination. Soil water retention curves and saturated hydraulic conductivities (Ksat) were estimated for all the samples using standard suction apparatus and the constant head method, respectively. The air entry suction (α) and pore size distribution (n) were generated using the RETC code. Results: The permanent wilting point and field capacity were at 0.081, 0.102, 0.107 and 0.121 and 0.188, 0.225, 0.241, 0.262 m3m-3 H2O, whilst its soil water diffusivity ranged from a low of 6.39, 6.94, 9.03 to a high of 12.5 cm2min-1 in the 0-15, 16-30, 31-45 and 46-60 cm depth, respectively. Ksat values from RETC code ranged from 29 - 48 cm day-1, while the total and readily available water within the soil profile were 330.4 and 214.7 mm H2O, respectively. Implication: The air entry value (α) and pore size distribution (n) implied an almost even distribution from the top and subsequent horizons. The soils ‘field capacity was achieved at pF 2.0 whilst PWP was arbitrary indicated at pF 4.2 reducing the time it takes to calculate irrigation cycles based on the amount of water available to the crops. Conclusion: The data indicates that pedo-transfer functions; especially high bulk densities negatively impact on soil hydraulics conductivity.
      PubDate: 2022-06-28
      DOI: 10.56369/tsaes.4200
      Issue No: Vol. 25, No. 3 (2022)
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Tel: +00 44 (0)131 4513762

Your IP address:
Home (Search)
About JournalTOCs
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-