for Journals by Title or ISSN
for Articles by Keywords
help
  Subjects -> AGRICULTURE (Total: 688 journals)
    - AGRICULTURAL ECONOMICS (73 journals)
    - AGRICULTURE (462 journals)
    - CROP PRODUCTION AND SOIL (90 journals)
    - DAIRYING AND DAIRY PRODUCTS (25 journals)
    - POULTRY AND LIVESTOCK (38 journals)

AGRICULTURE (462 journals)                  1 2 3 4 5 | Last

Aceh International Journal of Science and Technology     Open Access  
Acta agriculturae Slovenica     Open Access   (Followers: 5)
Acta Agrobotanica     Open Access   (Followers: 3)
Acta Agronomica Hungarica     Full-text available via subscription   (Followers: 1)
Acta Agronomica Sinica     Full-text available via subscription   (Followers: 6)
Acta Scientiarum. Animal Sciences     Open Access   (Followers: 1)
Acta Scientiarum. Technology     Open Access   (Followers: 1)
Acta Technologica Agriculturae     Open Access   (Followers: 3)
Advances in Agriculture & Botanics     Open Access   (Followers: 10)
Advances in Agriculture, Sciences and Engineering Research     Open Access   (Followers: 12)
Advances in Agronomy     Full-text available via subscription   (Followers: 11)
Advances in Life Science and Technology     Open Access   (Followers: 5)
AFBM Journal     Open Access  
Africa Development     Open Access   (Followers: 8)
Africa Research Bulletin: Political, Social and Cultural Series     Hybrid Journal   (Followers: 8)
African Journal of Agricultural Research     Open Access   (Followers: 3)
African Journal of Food Science     Open Access   (Followers: 4)
African Journal of Food, Agriculture, Nutrition and Development     Open Access   (Followers: 6)
African Journal of Horticultural Science     Open Access   (Followers: 2)
African Journal of Range and Forage Science     Hybrid Journal   (Followers: 5)
African Journal of Sustainable Development     Full-text available via subscription   (Followers: 5)
Agribusiness : an International Journal     Hybrid Journal   (Followers: 5)
Agricultura Tecnica     Open Access   (Followers: 6)
Agricultura Tropica et Subtropica     Open Access   (Followers: 2)
Agricultural Advances     Open Access   (Followers: 4)
Agricultural and Food Science     Open Access   (Followers: 19)
Agricultural Economics     Hybrid Journal   (Followers: 46)
Agricultural History     Full-text available via subscription   (Followers: 235)
Agricultural Research     Hybrid Journal   (Followers: 5)
Agricultural Science     Full-text available via subscription   (Followers: 6)
Agricultural Science     Open Access  
Agricultural Sciences     Open Access   (Followers: 8)
Agricultural Sciences in China     Full-text available via subscription   (Followers: 4)
Agricultural Systems     Hybrid Journal   (Followers: 21)
Agricultural Water Management     Hybrid Journal   (Followers: 16)
Agriculture     Open Access   (Followers: 5)
Agriculture & Food Security     Open Access   (Followers: 12)
Agriculture (Poľnohospodárstvo)     Open Access   (Followers: 1)
Agriculture and Agricultural Science Procedia     Full-text available via subscription   (Followers: 1)
Agriculture and Human Values     Hybrid Journal   (Followers: 11)
Agriculture, Ecosystems & Environment     Hybrid Journal   (Followers: 32)
Agriprobe     Full-text available via subscription  
Agrivita : Journal of Agricultural Science     Open Access   (Followers: 4)
Agro-Science     Full-text available via subscription  
Agroalimentaria     Open Access   (Followers: 1)
Agrociencia     Open Access   (Followers: 2)
Agrokémia és Talajtan     Full-text available via subscription   (Followers: 1)
Agronomía Colombiana     Open Access   (Followers: 1)
Agronomía Costarricense     Open Access   (Followers: 2)
Agronomía Mesoamericana     Open Access   (Followers: 1)
Agronomie Africaine     Full-text available via subscription  
Agronomy     Open Access   (Followers: 8)
Agrosearch     Open Access  
AI & Society     Hybrid Journal   (Followers: 2)
Alinteri Zirai Bilimler Dergisi : Alinteri Journal of Agricultural Sciences     Open Access  
Ambiência     Open Access  
Ambiente & Agua : An Interdisciplinary Journal of Applied Science     Open Access   (Followers: 1)
American Journal of Agricultural and Biological Sciences     Open Access   (Followers: 9)
American Journal of Botany     Full-text available via subscription   (Followers: 14)
American Journal of Economics and Sociology     Hybrid Journal   (Followers: 21)
American Journal of Potato Research     Hybrid Journal   (Followers: 2)
American Journal of Rural Development     Open Access   (Followers: 1)
Anais da Academia Brasileira de Ciências     Open Access   (Followers: 2)
Annales UMCS, Agricultura     Open Access  
Annales UMCS, Horticultura     Full-text available via subscription  
Annals of Agricultural and Environmental Medicine     Open Access   (Followers: 1)
Annals of Agricultural Sciences     Open Access   (Followers: 1)
Annual Review of Resource Economics     Full-text available via subscription   (Followers: 10)
APCBEE Procedia     Partially Free   (Followers: 2)
Applied Economics Letters     Hybrid Journal   (Followers: 22)
Applied Financial Economics Letters     Hybrid Journal   (Followers: 7)
Arboricultural Journal : The International Journal of Urban Forestry     Hybrid Journal   (Followers: 6)
Archivos de Zootecnia     Open Access   (Followers: 2)
Arquivos do Instituto Biológico     Open Access  
Arthropod-Plant Interactions     Hybrid Journal   (Followers: 1)
Asian Economic Papers     Hybrid Journal   (Followers: 3)
Asian Journal of Agricultural Research     Open Access   (Followers: 4)
Asian Journal of Plant Sciences     Open Access   (Followers: 2)
Australian Cottongrower, The     Full-text available via subscription   (Followers: 1)
Australian Economic Papers     Hybrid Journal   (Followers: 5)
Australian Forest Grower     Full-text available via subscription   (Followers: 2)
Australian Forestry     Full-text available via subscription   (Followers: 4)
Australian Grain     Full-text available via subscription   (Followers: 4)
Australian Holstein Journal     Full-text available via subscription  
Australian Journal of Agricultural and Resource Economics     Hybrid Journal   (Followers: 5)
Australian Journal of Agricultural Engineering     Open Access  
Australian Sugarcane     Full-text available via subscription  
Avances en Investigacion Agropecuaria     Open Access   (Followers: 1)
Bangladesh Journal of Agricultural Research     Open Access   (Followers: 2)
Bangladesh Journal of Scientific Research     Open Access   (Followers: 1)
Berkala Ilmiah Pertanian     Open Access   (Followers: 1)
Bioagro     Open Access   (Followers: 1)
Biocatalysis and Agricultural Biotechnology     Hybrid Journal   (Followers: 5)
Biocontrol Science and Technology     Hybrid Journal   (Followers: 5)
Biodiversity     Hybrid Journal   (Followers: 21)
Biodiversity : Research and Conservation     Open Access   (Followers: 20)
Biological Agriculture & Horticulture : An International Journal for Sustainable Production Systems     Partially Free   (Followers: 13)
Biosystems Engineering     Hybrid Journal   (Followers: 1)
Biotemas     Open Access  
Bragantia     Open Access   (Followers: 2)

        1 2 3 4 5 | Last

Journal Cover Advances in Agronomy
   [13 followers]  Follow    
   Full-text available via subscription Subscription journal
     ISSN (Print) 0065-2113
     Published by Elsevier Homepage  [2575 journals]   [SJR: 1.525]   [H-I: 59]
  • Gypsum Soils—Their Morphology, Classification, Function, and
           Landscapes
    • Abstract: Publication date: Available online 26 November 2014
      Source:Advances in Agronomy
      Author(s): Susan Casby-Horton , Juan Herrero , Nelson A. Rolong
      Gypsum soils are both a problem and a puzzle, which is precisely why they deserve attention. Gypseous (high-gypsum) soils generally occupy sparsely populated land with minimal land use intensity in arid and semiarid climates. Gypsum content in agricultural soils results in restricted water and nutrient retention and the potential for dissolution piping, primarily in response to irrigation. The corrosive effects of gypsum soils on concrete, metal, and building materials are also problematic. On the other hand, understanding the genesis and function of gypsiferous (low-gypsum) and gypseous soils is interesting and challenging, and our grasp of processes involved in the formation and behavior of these soils is critical for proper management for agricultural, rangeland, engineering, and construction purposes. The objective of this review was to examine the physical and chemical properties of gypsum and the impacts of these properties in the soil environment. The particular properties that gypsum presence imparts to soils affect soil development, including soil morphology. Accumulations of pedogenic gypsum influence water-holding capacity, nutrient and water availability for plants, root growth, and the standard concepts of soil texture and rupture resistance. Gypsum precipitation is also affected by the presence of more soluble salts. The development of physicochemical models that explain the formation and function of gypsiferous and gypseous soils is necessary if we hope to properly manage and maintain these unusual soils and their landscapes.


      PubDate: 2014-12-17T19:18:37Z
       
  • Models, Developments, and Perspectives of Mutual Legume Intercropping
    • Abstract: Publication date: Available online 26 November 2014
      Source:Advances in Agronomy
      Author(s): Aleksandar Mikić , Branko Ćupina , Diego Rubiales , Vojislav Mihailović , Lina Šarūnaitė , Joëlle Fustec , Svetlana Antanasović , Đorđe Krstić , Laurent Bedoussac , Lana Zorić , Vuk Đorđević , Vesna Perić , Mirjana Srebrić
      This paper presents the current state of our knowledge of mutual legume intercropping, with an emphasis on its utilization in continental and Mediterranean climates. Its novelty is primarily reflected in the carefully designed schemes for two main forms of mutual legume intercropping. The first one is establishing perennial forage legumes, such as red clover, alfalfa, and sainfoin, with annual legume, such as pea, where the latter acts as a bioherbicide and concurrently contributes to the total forage yield in the first cut of the former. Another form is intercropping annual legumes with each other respecting the same time of sowing, that is, in fall or in spring, similar growth habit, especially stem length, time of maturity for cutting or harvest, and that one component has good standing ability and supports the other one that is susceptible to lodging. Since the prominently pioneering character of this research, most of the presented results, both published and unpublished, shown here for the first time, deal with forage and grain yield and its economic reliability in the form of land equivalent ratio, since this would surely be of the primary interest to the farmers to get introduced with. The first and rather advanced efforts have also been made in the physiology, anatomy, and biotic stress of both forms of mutual intercropping schemes. We anticipate that, together with further research in the said fields along with underground aspects, will make mutual legume intercropping one of the most promising answers for protein-rich food and feed worldwide.


      PubDate: 2014-12-17T19:18:37Z
       
  • Mineral–Organic Associations: Formation, Properties, and Relevance
           in Soil Environments
    • Abstract: Publication date: Available online 16 December 2014
      Source:Advances in Agronomy
      Author(s): Markus Kleber , Karin Eusterhues , Marco Keiluweit , Christian Mikutta , Robert Mikutta , Peter S. Nico
      Minerals and organic matter (OM) may form intricate associations via myriad interactions. In soils, the associations of OM with mineral surfaces are mainly investigated because of their role in determining the long-term retention of OM. OM “must decay in order to release the energy and nutrients that drive live processes all over the planet” (Janzen, 2006). Thus, the processes and mechanisms that retain OM in soil are a central concern to very different branches of environmental research. An agronomist may want to synchronize periods of high nutrient and energy release with the growth stages of a crop. An environmental chemist may wish to either immobilize an organic soil contaminant or enhance its decomposition into less harmful metabolites, while climate scientists need to understand the processes that mediate the production of potent greenhouse gases from decomposing OM. Associations of OM with pedogenic minerals (henceforth termed mineral–organic associations (MOAs)) are known to be key controls in these and many other processes. Here we strive to present an overview of the current knowledge on MOAs and identify key questions and future research needs.


      PubDate: 2014-12-17T19:18:37Z
       
  • Weeds of Direct-Seeded Rice in Asia: Problems and Opportunities
    • Abstract: Publication date: Available online 20 November 2014
      Source:Advances in Agronomy
      Author(s): Amar Matloob , Abdul Khaliq , Bhagirath Singh Chauhan
      Rice production symbolizes the single largest land use for food production on the Earth. The significance of this cereal as a source of energy and income seems overwhelming for millions of people in Asia, representing 90% of global rice production and consumption. Estimates indicate that the burgeoning population will need 25% more rice by 2025 than today's consumption. As the demand for rice is increasing, its production in Asia is threatened by a dwindling natural resource base, socioeconomic limitations, and uncertainty of climatic optima. Transplanting in puddled soil with continuous flooding is a common method of rice crop establishment in Asia. There is a dire need to look for rice production technologies that not only cope with existing limitations of transplanted rice but also are viable, economical, and secure for future food demand. Direct seeding of rice has evolved as a potential alternative to the current detrimental practice of puddling and nursery transplanting. The associated benefits include higher water productivity, less labor and energy inputs, less methane emissions, elimination of time and edaphic conflicts in the rice–wheat cropping system, and early crop maturity. Realization of the yield potential and sustainability of this resource-conserving rice production technique lies primarily in sustainable weed management, since weeds have been recognized as the single largest biological constraint in direct-seeded rice (DSR). Weed competition can reduce DSR yield by 30–80% and even complete crop failure can occur under specific conditions. Understanding the dynamics and outcomes of weed–crop competition in DSR requires sound knowledge of weed ecology, besides production factors that influence both rice and weeds, as well as their association. Successful adoption of direct seeding at the farmers' level in Asia will largely depend on whether farmers can control weeds and prevent shifts in weed populations from intractable weeds to more difficult-to-control weeds as a consequence of direct seeding. Sustainable weed management in DSR comprises all the factors that give DSR a competitive edge over weeds regarding acquisition and use of growth resources. This warrants the need to integrate various cultural practices with weed control measures in order to broaden the spectrum of activity against weed flora. A weed control program focusing entirely on herbicides is no longer ecologically sound, economically feasible, and effective against diverse weed flora and may result in the evolution of herbicide-resistant weed biotypes. Rotation of herbicides with contrasting modes of action in conjunction with cultural measures such as the use of weed-competitive rice cultivars, sowing time, stale seedbed technique, seeding rate, crop row spacing, fertilizer and water inputs and their application method/timing, and manual and mechanical hoeing can prove more effective and need to be optimized keeping in view the type and intensity of weed infestation. This chapter tries to unravel the dynamics of weed–crop competition in DSR. Technological issues, limitations associated with DSR, and opportunities to combat the weed menace are also discussed as a pragmatic approach for sustainable DSR production. A realistic approach to secure yield targets against weed competition will combine the abovementioned strategies and tactics in a coordinated manner. This chapter further suggests the need of multifaceted and interdisciplinary research into ecologically based weed management, as DSR seems inevitable in the near future.


      PubDate: 2014-12-17T19:18:37Z
       
  • The Use of Biostimulants for Enhancing Nutrient Uptake
    • Abstract: Publication date: Available online 20 November 2014
      Source:Advances in Agronomy
      Author(s): Moshe Halpern , Asher Bar-Tal , Maya Ofek , Dror Minz , Torsten Muller , Uri Yermiyahu
      Fertilizer use in modern agriculture is highly inefficient; much of the applied fertilizer is released into the environment, causing environmental degradation. One way in which fertilizer use can be reduced without damaging plant nutrition is to enhance crop uptake of nutrients through the use of biostimulants. A broad definition of plant biostimulants, including substances sometimes categorized as biofertilizers or biopesticides, is used throughout this review: “Plant biostimulants are substances or materials, with the exception of nutrients and pesticides, which, when applied to plants, seeds, or growing substrates in specific formulations, have the capacity to modify physiological processes in plants in a way that provides potential benefits to growth, development, or stress response.” This definition includes a variety of substances, four of which will be reviewed in this article: seaweed extract, humic substances, amino acids, and plant-growth-promoting bacteria. We will concentrate on the positive effects of biostimulant application on plant nutrient uptake, and the underlying mechanisms, which include positive changes in soil structure or nutrient solubility, root morphology, plant physiology, and symbiotic relationships, will be discussed. Recommendations for future research directions include finding the most promising substances, isolating the active ingredients and clearly demonstrating the mechanisms by which they affect nutrient uptake. The beneficial effects and mechanisms must be consistently demonstrated in greenhouse and field experiments.


      PubDate: 2014-12-17T19:18:37Z
       
  • The Challenge of the Urine Patch for Managing Nitrogen in Grazed Pasture
           Systems
    • Abstract: Publication date: Available online 18 November 2014
      Source:Advances in Agronomy
      Author(s): Diana R. Selbie , Laura E. Buckthought , Mark A. Shepherd
      Ruminants excrete as much as 70–95% of the nitrogen (N) they consume. The urine patch is the conduit through which much of this N is recycled in grazed pasture systems. This chapter focuses on three key areas: urine patch characteristics and N cycling processes; implications for N cycling at the farm and paddock scale; and strategies available to mitigate N losses from the urine patch. The urine patch N loading rate is a key metric for quantifying and modeling fate of N; yet it is a derived value, relying on estimates of urine volume and N concentration, and the urine patch surface area, all of which are variable. Much is known about N cycling processes in the urine patch but further understanding of N loss, leaching of dissolved organic N, and mineralization–immobilization turnover is needed. Typical values (as a percentage of the deposited urinary N) were estimated as: 13% ammonia volatilization; 2% nitrous oxide emission; 20% nitrate leaching; 41% pasture uptake; 26% gross immobilization. The relative importance of each process is influenced by urine patch characteristics and environmental factors. Models are an important tool for scaling from the individual urine patch to the paddock and farm scale, though accounting for variability in urine patch characteristics, and spatial and temporal distribution, remains a challenge. Many potential management strategies to decrease N loss from the urine patch are still at the proof of concept stage with few actually deployed on the farm. Further research is required to integrate these into farm management systems.


      PubDate: 2014-12-17T19:18:37Z
       
  • Biologically Regulated Nutrient Supply Systems: Compost
           and Arbuscular Mycorrhizas—A Review
    • Abstract: Publication date: Available online 18 November 2014
      Source:Advances in Agronomy
      Author(s): Timothy R. Cavagnaro
      To achieve global food security, we will need to produce more food, and do so in an environmentally sustainable manner. Inorganic fertilizers have been instrumental in increasing food production, but with some fertilizers becoming increasingly scarce and expensive, we also need to consider other options for providing agricultural plants with nutrients. To this end, there has been increased interest in the potential to make better use of the nutrients tied up in organic matter; composts are an example of this, and are the focus of this review. Plant nutrient acquisition can be enhanced through the formation of arbuscular mycorrhizas (AM). The purpose of this review is to explore interactions between compost and AM, with an emphasis on the impacts of compost addition and formation and functioning of AM. Based on available literature, it is clear that the application of compost either has a positive or neutral effect on the formation of the symbiosis, and that dual application of compost and arbuscular mycorrhizal fungi (AMF) provides clear benefits to plants in terms of growth and nutrition. There is also emerging evidence that dual application also provides benefits in terms of soil structure. Taken together, the conclusion of this review is that the biologically regulated nutrient supply systems based on compost and AM are compatible.


      PubDate: 2014-12-17T19:18:37Z
       
  • Climate Change: Implications for Stakeholders in Genetic Resources and
           Seed Sector
    • Abstract: Publication date: Available online 18 November 2014
      Source:Advances in Agronomy
      Author(s): Rishi P. Singh , P.V. Vara Prasad , K. Raja Reddy
      The characteristic of climatic change is increase in the frequency of extreme events that are likely to decrease crop yield. The geographic areas that are currently most food-insecure are likely to be most affected by changing climates. Climate change is likely to affect all dimensions of crop production. Agricultural crop production depends upon the timely availability of good-quality seeds in adequate quantity at affordable prices to the farming communities. Genetic diversity and breeding for improved stress-tolerant genotypes are key elements in tackling climate change. Plant genetic resources (PGRs) are important sources for developing new and improved varieties. The loss of these genetic resources due to climate change will deprive source of diversity and tolerance. Currently, more emphasis has been placed for ex situ conservation, while equally if not more urgency is required to conserve the PGRs in in situ. At present, a number of international agreements are enforced for germplasm exchange and utilization. Some of the important methods to develop and disseminate new cultivars include breeding new crop varieties for wider adaptation under adverse climatic conditions using both classical and modern approaches and seed production through participatory approaches. Participatory breeding programs have successfully led to the development and dissemination of varieties in cereals. Seed industry plays an important role in increasing productivity of crops. The adverse effect of climate change on the seed industry can be minimized by developing efficient seed management systems: breeding, seed production, seed certification, and seed trade. Some efficient systems include adjustment of crop calendars for quality seed production, management of pollinators, strengthening hybrid seed production, postharvest management of seed, seed treatment technologies, seed processing, and seed storage. For faster and timely development, partnerships (public and private) at various levels (regional and international) are crucial. There is an urgent need to strengthen both formal and informal seed systems including characterization of environment to find suitable geographic regions for quality seed production. For seed certification, harmonization of various international seed certification schemes/programs and seed testing procedures are essential. This will also help in efficient and safe movement of seed. To influence seed trade, the effective management of intellectual property rights, sanitary and phytosanitary certificates in addition to management of trade barriers, are all of prime importance for growth of the seed industry. In both developed and developing nations, public investments in plant breeding and seed industry are on the decline. This trend needs to be reversed by emphasizing the need to increase research funding to all stakeholders of genetic resources and seed industry to develop strategies to mitigate the negative impacts of climate change on agricultural systems.


      PubDate: 2014-12-17T19:18:37Z
       
  • Weedy (Red) Rice: An Emerging Constraint to Global Rice Production
    • Abstract: Publication date: Available online 18 November 2014
      Source:Advances in Agronomy
      Author(s): Lewis H. Ziska , David R. Gealy , Nilda Burgos , Ana L. Caicedo , Jonathan Gressel , Amy L. Lawton-Rauh , Luis A. Avila , Giovani Theisen , Jason Norsworthy , Aldo Ferrero , Francesco Vidotto , David E. Johnson , Felipe G. Ferreira , Enio Marchesan , Valmir Menezes , Marc A. Cohn , Steven Linscombe , Luciano Carmona , Rui Tang , Aldo Merotto Jr.
      Ongoing increases in the human population necessitate that rice will continue to be a critical aspect of food security for the twenty-first century. While production must increase in the coming decades to meet demand, such increases will be accompanied by diminished natural resources and rising production costs that will alter how rice is grown and managed. Such resource constraints are the impetus for the ongoing transition from traditional flooding and transplanting to direct-seeded rice (DSR). However, such a transition can result in an increase in pest pressures, especially weeds. Rice production can be particularly vulnerable to weed competition, with significant yield losses (i.e., >50%) occurring. Among pernicious weeds, weedy (red) rice (Oryza sativa L.) is increasingly recognized as a major constraint in achieving maximum yield in DSR. Weedy rice is congeneric to crop rice with phenotypic similarity; hence, its ability to negatively influence qualitative and quantitative aspects of production is substantial. As rice will continue to serve as a cornerstone for future food security and sustainability, a comprehensive assessment of weedy rice impacts associated with increasing adoption of DSR is both timely and critical. In this chapter, we examine the biological basis for the competitive ability of weedy rice, including its evolution, ecophysiology, and genetics; quantify spatial–temporal shifts in its distribution and spread; and emphasize and outline a number of regional and global management strategies for its detection and control. Lastly, a number of critical research areas are suggested that deserve additional scrutiny with respect to weedy rice management.


      PubDate: 2014-12-17T19:18:37Z
       
  • Advances in Host Plant and Rhizobium Genomics to Enhance Symbiotic
           Nitrogen Fixation in Grain Legumes
    • Abstract: Publication date: Available online 18 November 2014
      Source:Advances in Agronomy
      Author(s): Sangam L. Dwivedi , Kanwar L. Sahrawat , Hari D. Upadhyaya , Alessio Mengoni , Marco Galardini , Marco Bazzicalupo , Emanuele G. Biondi , Mariangela Hungria , Glaciela Kaschuk , Matthew W. Blair , Rodomiro Ortiz
      Legumes form symbiotic relationship with root-nodule, rhizobia. The nitrogen (N2) fixed by legumes is a renewable source and of great importance to agriculture. Symbiotic nitrogen fixation (SNF) is constrained by multiple stresses and alleviating them would improve SNF contribution to agroecosystems. Genetic differences in adaptation tolerance to various stresses are known in both host plant and rhizobium. The discovery and use of promiscuous germplasm in soybean led to the release of high-yielding cultivars in Africa. High N2-fixing soybean cultivars are commercially grown in Australia and some countries in Africa and South America and those of pea in Russia. SNF is a complex trait, governed by multigenes with varying effects. Few major quantitative trait loci (QTL) and candidate genes underlying QTL are reported in grain and model legumes. Nodulating genes in model legumes are cloned and orthologs determined in grain legumes. Single nucleotide polymorphism (SNP) markers from nodulation genes are available in common bean and soybean. Genomes of chickpea, pigeonpea, and soybean; and genomes of several rhizobium species are decoded. Expression studies revealed few genes associated with SNF in model and grain legumes. Advances in host plant and rhizobium genomics are helping identify DNA markers to aid breeding of legume cultivars with high symbiotic efficiency. A paradigm shift is needed by breeding programs to simultaneously improve host plant and rhizobium to harness the strength of positive symbiotic interactions in cultivar development. Computation models based on metabolic reconstruction pathways are providing greater insights to explore genotype–phenotype relationships in SNF. Models to simulate the response of N2 fixation to a range of environmental variables and crop growth are assisting researchers to quantify SNF for efficient and sustainable agricultural production systems. Such knowledge helps identifying bottlenecks in specific legume–rhizobia systems that could be overcome by legume breeding to enhance SNF. This review discusses the recent developments to improve SNF and productivity of grain legumes.


      PubDate: 2014-12-17T19:18:37Z
       
  • Advances in Agronomy
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 128




      PubDate: 2014-12-17T19:18:37Z
       
  • Front Matter
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 128




      PubDate: 2014-12-17T19:18:37Z
       
  • Copyright
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 128




      PubDate: 2014-12-17T19:18:37Z
       
  • Contributors
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 128




      PubDate: 2014-12-17T19:18:37Z
       
  • Preface
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 128
      Author(s): Donald L. Sparks



      PubDate: 2014-12-17T19:18:37Z
       
  • Chapter One Advances in Portable X-ray Fluorescence (PXRF) for
           Environmental, Pedological, and Agronomic Applications
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 128
      Author(s): David C. Weindorf , Noura Bakr , Yuanda Zhu
      Contemporary soil, agronomic, and environmental investigations require high quality data for the development of sound management decisions. For years, X-ray fluorescence (XRF) spectrometry has been known to provide accurate elemental data in a wide range of matrices. However, advances in the past two decades have now made the technology portable. Improvements to spectrometer design have led to the replacement of many active source X-ray units with X-ray tubes that only emit X-rays when energized. Several generations of detector improvement have resulted in the current standard for many units, the silicon drift detector, which is capable of much lower limits of detection than its predecessors. Field portable X-ray fluorescence (PXRF) spectrometers offer many advantages over traditional techniques including speed, portability, wide dynamic range of elemental quantification, little/no need for sample pretreatment, and simplicity. Furthermore, PXRF analyses are nondestructive, allowing for analyzed samples to be preserved for future use. This review presents an overview of the development, operational theory, and contemporary uses of PXRF. Also, benefits and limitations to PXRF use are presented. Many industrial uses are covered, but deference is paid to rapidly advancing environmental, pedological, and agronomic applications of PXRF. Summarily, PXRF offers a range of benefits not possible with traditional laboratory techniques.


      PubDate: 2014-12-17T19:18:37Z
       
  • Chapter Two Environmental Chemistry and Toxicology of Iodine
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 128
      Author(s): Ethan M. Cox , Yuji Arai
      Iodine is a trace halide found in the environment. A majority of global iodine budget resides in ocean while lithosphere and pedosphere contain the rest limiting the bioavailability of iodine in terrestrial environment. Iodine cycles involve the multivalence state chemical speciation at the air–water–sediment interfaces. The mobility and reactivity of these inorganic and organic iodine species are impacted by changes in physicochemical factors (e.g., pH and ionic strength), and macro- and micro-biological activities. Although iodine aqueous biogeochemistry has been extensively investigated in marine systems in the past, the partitioning mechanisms of iodine at the geomedia–water interface remained poorly understood. This chapter covers environmental soil chemistry of iodine and the impact to human and ecological health.


      PubDate: 2014-12-17T19:18:37Z
       
  • Chapter Three Guttation New Insights into Agricultural Implications
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 128
      Author(s): Sanjay Singh
      The survival of all plants depends on their abilities to obtain, retain and transport a variety of substances into, through, and out of their bodies. Guttation is one of these abilities to exude fluids out of leaves in the form of droplets through special structures called “hydathodes.” These hydathodes are principally located at the tips and margins or edges of the leaves. Guttation is a biophysicochemical and physiological phenomenon in plants which is often noticed in the early morning in a wide range of plant species including angiosperms, gymnosperms, algae, and fungi. The water droplets exuded by guttation contain both the organic and inorganic substances including microorganisms and trickle down from the exuding sites bathing the soil surface and plant residues lying underneath. The main physiological roles of guttation consisting of essentially xylem and phloem saps driven by root pressure involve the transport of water, nutrients, metabolites, hormones, enzymes, transport proteins, pathogenesis-related proteins, etc. within the plants impacting their growth, development, biological, and economic yield. Thus, it serves a variety of purposes in plants. It may also serve as valve for release of excess hydrostatic pressure. Guttation has been shown to play a crucial role in controlling leaf senescence and photosynthesis. Its intensity has been found to be an indicator of root activity. The role of hydathodes has been suggested to be crucial in maintaining water status of plants enabling them survive and grow under water-limited situations. The guttation fluids have tendency to enrich soil fertility and improve its biochemistry by adding and activating certain enzymes such as peroxidases which catalyze the oxidative cross-linking and polymerization of certain organic compounds by hydrogen peroxide and other organic peroxides. The exudation of certain compounds having natural herbicidal effect on other plants helps exercise control over ecological balance among plant communities. Further, it may also serve as a noninvasive assessment test for pesticide residues in plants facilitating proper plant protection measures. It is of great significance that guttation is a means of excreting excess of harmful elements such as Ni, Se, etc. from metal-enriched soils thereby promoting plant growth on such inhospitable soils. Of particular interest is the fact that the variation in color of guttation fluids caused by the presence of different species of fungi therein provides a useful tool for taxonomic classification of certain fungi. Though guttation fluids are considered to be an ideal habitat for pathogen development causing some diseases however, they also contain antimicrobial phylloplane proteins that not only protect plants from certain diseases, they rather elevate disease resistance of certain field crops as well. Guttation fluids may also be used for the production of pharmaceuticals by transgenic plants. However, nutrient losses through guttation at times may be of sufficient magnitude to alter markedly the behavior of the plant. Taken all together, it may be summarized that guttation may be viewed as an efficient barometer for gauging internal chemical strategies translating into increased plant growth, development, and productivity.


      PubDate: 2014-12-17T19:18:37Z
       
  • Chapter Four Assessing Nutrient Use Efficiency and Environmental Pressure
           of Macronutrients in Biobased Mineral Fertilizers A Review of Recent
           Advances and Best Practices at Field Scale
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 128
      Author(s): Céline Vaneeckhaute , Greet Ghekiere , Evi Michels , Peter A. Vanrolleghem , Filip M.G. Tack , Erik Meers
      Anaerobic digestion is an established technology to convert biowaste into renewable energy and nutrient-rich digestates. Nutrient recovery from these digestates as renewable fertilizers with high-nutrient use efficiency or as P-poor alternative fertilizers has gained increased attention in order to meet both regulatory drivers and market demands, while producing an internal revenue source. However, until now, this opportunity has been difficult to realize due to obstacles and inconsistencies in legislative systems, and lack of insights into the composition and properties of these products, as well as in their impact on crop yield and soil quality. The aim of this review is to prove the effectiveness of fertilization strategies using biodigestion waste derivatives as compared to conventional practices using animal manure and chemical fertilizers. As adequate field-scale data are lacking in the literature, a ground-breaking three-year field trial has been performed. The value and impact of these biobased fertilizers are demonstrated by the use of high-level performance indicators measuring farming pressure on the environment and how that pressure is changing over time. Bottlenecks for marketing and legislative constraints are discussed. An economic and ecological evaluation is also assessed. The proof of concept provided in this chapter should help to better classify these biobased products into fertilizer and environmental legislations and serve as a support to stimulate their use in the farming community. Moreover, this review should stimulate and provide guidance for further field research on biobased fertilizers, which is highly essential in the development and implementation of more effective and environmentally friendly farming strategies.


      PubDate: 2014-12-17T19:18:37Z
       
  • Chapter Five Exploring Options for Lowland Rice Intensification under
           Rain-fed and Irrigated Ecologies in East and Southern Africa The Potential
           Application of Integrated Soil Fertility Management Principles
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 128
      Author(s): Nhamo Nhamo , Gerald Kyalo , Virgilio Dinheiro
      Increased rice production in East and Southern Africa explains the crucial role rice plays in household food and income security. However, in last three decades, rice productivity per unit area has stagnated due to abiotic and biotic factors, hence the need for the application of Integrated Soil Fertility Management (ISFM) principles. Farmyard manure, crop residues are central to improving soil fertility in rice systems. Compared to mineral fertilizer, organic manure use results in higher rice yield gains. Symbiotic biological nitrogen fixation (BNF) by grain legumes has been successfully applied to improve rice yields. However, only a few legumes are suitable for use under flooded conditions. Application of Azolla sp. improves rice yields though drought and the need for inoculum limit widespread adoption. Poor quality organic fertilizers limit their effectiveness as macronutrient sources. Where soils are P deficient, BNF and animal manure technologies seem to be of little value. In conclusion, combinations of mineral fertilizers, farmyard manure, and short seasoned legumes have the potential of improving rice yields. Further research on the application of ecology specific ISFM technologies is required in view of land degradation and climate variability. Research is needed on suitable legumes, fertilizer equivalency values of organics, fortification of organic fertilizers, and effectiveness of combinations of mineral and organic fertility inputs. We propose a step-by-step innovative approach to improving rice productivity by incorporating the components of ISFM at different stages. Decision guides essential to improved adoption and increased investment on rice production systems are required.


      PubDate: 2014-12-17T19:18:37Z
       
  • Chapter Six Management of Soil Acidity of South American Soils for
           Sustainable Crop Production
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 128
      Author(s): Nanda K. Fageria , Adriano S. Nascente
      A burgeoning global population is creating unprecedented demands on agriculture to produce ever-increasing amounts of food, fiber, and fuel. In this context, South America has the largest land area in the world that can be used to meet food and fiber demand. In addition, South America also has the largest amount of fresh or potable water globally and favorable climatic conditions throughout the year, which further enhances the role of this continent in providing world food supply. The Brazilian Cerrado, or savanna, a total area of about 205 million ha of acid soils is a good case in point. Similarly, Colombia, Bolivia, Venezuela, Peru, and Ecuador also have large land areas, which can be utilized for crop production. However, the major soils of this continent are acidic and infertile. Hence, liming and fertilizer application are essential. Soil acidity is mainly caused by leaching of bases from soil profile, soils may be acidified with acid deposition from the atmosphere, use of ammoniacal fertilizers, by proton generation in the soil, mineralization of organic matter, intensive crop cultivation, and from N2 fixation by legumes. Important indices that are used in correcting soil acidity for maximizing crop yields are pH, base saturation, aluminum saturation, acidity saturation, calcium saturation, magnesium saturation, and potassium saturation. Sometimes, calcium/magnesium ratio, calcium/potassium ratio, and magnesium/potassium ratio are also used as soil acidity indices in crop production. Optimal values of these soil acidity indices varied with type of soil, crop species, and cultivar or genotypes within species. Management practices that can be adopted in improving crop yields on acid soils are liming, gypsum application, and the use of an adequate rate of fertilizers and organic manures. The use of acidity tolerant crop species or cultivars within species is another important strategy in improving crop yields on acid soils.


      PubDate: 2014-12-17T19:18:37Z
       
  • Chapter Four Improving Water Productivity of Wheat-Based Cropping Systems
           in South Asia for Sustained Productivity
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 127
      Author(s): Yadvinder-Singh , Surinder S. Kukal , Mangi Lal Jat , Harminder S. Sidhu
      Serious water deficits are threatening agricultural sustainability in many regions of the South Asia (SA). While the increase in crop production of irrigated rice–wheat system in SA has been impressive since the 1970s, the low water productivity (WP) has led to the depletion of surface water and groundwaters. In this chapter we have discussed the availability of water resources in SA, identified the positive effects of soil and water management and crop genetic improvement on WP, and then described knowledge gaps and research priorities to further improve the WP with special emphasis on wheat-based cropping systems in irrigated and rainfed regions of SA. A single approach would not be able to tackle the forthcoming challenge of producing more food and fiber with limited or even reduced available water. Integrating irrigation water-saving techniques (water-saving irrigation methods, deficit irrigation, modernization of irrigation system, etc.) with agronomic and soil manipulations viz., optimum irrigation scheduling, direct-seeded rice, alternate wetting and drying in puddle transplanted rice, raised bed planting, crop diversification, conservation tillage, crop residue management, and conjunctive use of good quality (canal) water. Improved soil water management practices for rainfed regions include reducing runoff, rainwater harvesting and recycling, conserving rainwater in the root zone by reducing evaporation losses, and optimal nutrient management. The low WP in farmer’s fields compared with well-managed experimental sites indicates the need for more efforts to transfer water-saving technologies to the farmers. In future we need to increase scientific understanding of the effects of agronomic management on WP across various soil and climate conditions; improve irrigation practices (timing and amounts) and methods (drip and sprinkler) based on real-time monitoring of water status in soil-crop systems; and maximize WP by managing water resources and allocation at regional scales in wheat-based cropping systems.


      PubDate: 2014-07-29T01:19:07Z
       
  • Chapter Three Agronomic and Physiological Responses to High Temperature,
           Drought, and Elevated CO2 Interactions in Cereals
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 127
      Author(s): Niteen N. Kadam , Gui Xiao , Reneeliza Jean Melgar , Rajeev N. Bahuguna , Cherryl Quinones , Anandhan Tamilselvan , Pagadala Vara V. Prasad , Krishna S.V. Jagadish
      Cereals such as rice, wheat, maize, and barley account for major proportion of global food grain production. High temperature, drought, and other climate change drivers are predicted to increase in frequency and magnitude, posing serious challenges to sustain global food production under changing climate. These climate change drivers often interact with each other under realistic field conditions resulting in impacts that are notably different compared to individual stress exposure. Till date, there has been no systematic synthesis comparing the impacts of different combinations of high temperature, drought, and elevated CO2 [eCO2], across cereals. Hence, the major objective of this chapter is to capture the overall agronomic and physiological impact of different combinations of these three factors compared with their independent exposure. High temperature or drought affects almost all growth and developmental phases during crop cycle leading to significant decline in photosynthesis, floral abnormalities, spikelet/kernel sterility, grain yield, and quality losses. Combined high temperature and drought stress can result in additive detrimental effect on growth physiology and productivity. On the other hand, interactive effect of [eCO2] with either high temperature or drought varies with species (C3 and C4), and also depends on other factors such as phenological stage, intensity and duration of stress, etc. Constraints and available avenues for breeding multiple abiotic stress tolerant cereals, role of modern genomic tools, precision phenotyping, and trait-based breeding program are highlighted. Finally, the chapter summarizes future research direction, in addressing combined stress resilience to ensure sustained global food security under warmer and drier climate.


      PubDate: 2014-07-29T01:19:07Z
       
  • Chapter Two Nature of the Belowground Ecosystem and Its Development during
           Pedogenesis
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 127
      Author(s): Richard John Haynes
      While much is known regarding the development of plant communities during primary succession and concomitant pedogenesis, considerably less is known regarding the development of soil microbial and soil fauna communities. In view of the importance of soil biota to soil processes, the nature of the belowground ecosystem and its development during pedogenesis is reviewed and discussed using recent chronosequence studies. During primary succession plant communities characteristically turnover several times. By contrast, community development for soil biota is characterized by progressive addition with many pioneer species remaining throughout soil development. In general, the size and diversity of soil biotic communities increases rapidly during the first 20–50years and then more or less stabilizes after hundreds of years, while plant biomass and soil organic matter content do not reach a peak for many hundreds or even thousands of years. The development of the soil faunal community is less rapid than that of the microbial community because dispersal is slower and in addition some faunal species require a certain depth of organic topsoil and/or litter layer before high populations develop. With increasing successional time the food web (based on organic detritus) becomes increasingly complex. Based on the reviewed data, a conceptual model of changes in plant, soil microbial, and soil faunal communities that occur during succession is presented. The significance of such changes to restoration of unweathered mine tailings is also discussed.


      PubDate: 2014-07-29T01:19:07Z
       
  • Preface
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 127




      PubDate: 2014-07-29T01:19:07Z
       
  • Chapter One The Global Dispersion of Pathogenic Microorganisms by Dust
           Storms and Its Relevance to Agriculture
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 127
      Author(s): Cristina Gonzalez-Martin , Nuria Teigell-Perez , Basilio Valladares , Dale W. Griffin
      Dust storms move an estimated 500–5000Tg of soil through Earth’s atmosphere every year. Dust-storm transport of topsoils may have positive effects such as fertilization of aquatic and terrestrial ecosystems and the evolution of soils in proximal and distal environments. Negative effects may include the stripping of nutrient-rich topsoils from source regions, sandblasting of plant life in downwind environments, the fertilization of harmful algal blooms, and the transport of toxins (e.g., metals, pesticides, herbicides, etc.) and pathogenic microorganisms. With respect to the long-range dispersion of microorganisms and more specifically pathogens, research is just beginning to demonstrate the quantity and diversity of organisms that can survive this type of transport. Most studies to date have utilized different assays to identify microorganisms and microbial communities using predominately culture-based, and more recently nonculture-based, methodologies. There is a clear need for international-scale research efforts that apply standardized methods to advance this field of science. Here we present a review of dust-borne microorganisms with a focus on their relevance to agronomy.


      PubDate: 2014-07-29T01:19:07Z
       
  • Contributors
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 127




      PubDate: 2014-07-29T01:19:07Z
       
  • Copyright
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 127




      PubDate: 2014-07-29T01:19:07Z
       
  • Front Matter
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 127




      PubDate: 2014-07-29T01:19:07Z
       
  • Advances in Agronomy
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 127




      PubDate: 2014-07-29T01:19:07Z
       
  • Chapter Four Disease and Frost Damage of Woody Plants Caused by
           Pseudomonas syringae Seeing the Forest for the Trees
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 126
      Author(s): Jay Ram Lamichhane , Leonardo Varvaro , Luciana Parisi , Jean-Marc Audergon , Cindy E. Morris
      Pseudomonas syringae is a phytopathogenic bacterium that causes diseases of monocots, herbaceous dicots, and woody dicots, worldwide. On woody plants, reports of disease due to P. syringae have markedly increased in the last years and the diseases have been recognized as a major threat to the primary products of agroforestry practices. Detection in Italy of a new highly aggressive population of P. syringae in 2008 on kiwifruit, which caused severe epidemics in the following years throughout the kiwifruit-growing areas of Asia, Europe, Oceania, and South America, rendered the entire kiwifruit industry vulnerable to the disease. Similarly, occurrence of an aggressive population of P. syringae on horse chestnut in 2002 in the Netherlands has rapidly established itself as a major threat to horse chestnut throughout Northwest Europe. To better understand the origin of such disease epidemics, a thorough knowledge of the pathogen is needed in sensu lato. Here, we report the most important features of the pathogen and its hosts in an attempt to clarify some key aspects. In particular, the diseases and the economic losses they cause, disease epidemiology, pathogen diversity, and the possible means of disease control have been discussed throughout the manuscript. In addition to the ability to cause the disease, the damage caused to woody plants through the ice nucleation activity of this bacterium is discussed.


      PubDate: 2014-06-18T20:42:54Z
       
  • Chapter Three The Physiology of Potassium in Crop Production
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 126
      Author(s): Derrick M. Oosterhuis , Dimitra A. Loka , Eduardo M. Kawakami , William T. Pettigrew
      Potassium (K) plays a major role in the basic functions of plant growth and development. In addition, K is also involved in numerous physiological functions related to plant health and tolerance to biotic and abiotic stress. However, deficiencies occur widely resulting in poor growth, lost yield, and reduced fiber quality. This review describes the physiological functions of K and the role in stress relief and also provides some agronomic aspects of K requirements, diagnosis of soil and plant potassium status, and amelioration. The physiological processes described include enzymes and organic compound synthesis regulation, water relations and stomates, photosynthesis, transport, cell signaling, and plant response to drought stress, cold stress, salt stress, as well as biotic stresses.


      PubDate: 2014-06-18T20:42:54Z
       
  • Chapter Two Water-Saving Innovations in Chinese Agriculture
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 126
      Author(s): Qiang Chai , Yantai Gan , Neil C. Turner , Ren-Zhi Zhang , Chao Yang , Yining Niu , Kadambot H.M. Siddique
      Water scarcity, water pollution, and water-related waste threaten humanity globally, largely due to the limited supply of freshwater on the planet, the unbalanced distribution of water resources, and the excessive consumption of water from the growing population and its economic development. China is facing severe water shortages; the northern part of the country has an average freshwater availability of 760cubic meter per capita per year, 25% below the internationally accepted threshold for water scarcity. Agriculture in northwest China relies on annual precipitation of 50–500mm, 70% of which occurs from July to September, and annual evaporation from 1500 to 2600mm. In the Hexi Corridor regions where annual precipitation is below 150mm, farming largely depends on irrigation with water from Qilian Mountain snowmelt. However, permanent snow on the mountain has moved upwards at a rate of 0.2–1.0m annually, and groundwater in the valley has declined at a rate of 0.5–1.8myear−1. Consequently, some natural oases, along the old Silk Road, have shrunk or disappeared and wells have dried up. At the meantime, some farms use irrigation water at a rate as high as 11,000m3 ha−1, much greater than crop water requirements for high yield. In recent years, many innovative research projects have dealt with the water issue in arid and semiarid northwestern China. In this chapter, we summarize some key water-saving technologies developed from some of these recently completed research projects, and discuss integrated and innovative approaches for the development of water-saving agricultural systems. Our goal is to encourage the use of innovative water-saving technologies to reduce agricultural water use, increase crop water-use efficiency, and improve agricultural productivity.


      PubDate: 2014-06-18T20:42:54Z
       
  • Preface
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 126
      Author(s): Donald L. Sparks



      PubDate: 2014-06-18T20:42:54Z
       
  • Chapter One Soil Chemical Insights Provided through Vibrational
           Spectroscopy
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 126
      Author(s): Sanjai J. Parikh , Keith W. Goyne , Andrew J. Margenot , Fungai N.D. Mukome , Francisco J. Calderón
      Vibrational spectroscopy techniques provide a powerful approach to the study of environmental materials and processes. These multifunctional analytical tools can be used to probe molecular vibrations of solid, liquid, and gaseous samples for characterizing materials, elucidating reaction mechanisms, and examining kinetic processes. Although Fourier transform infrared (FTIR) spectroscopy is the most prominent type of vibrational spectroscopy used in the field of soil science, applications of Raman spectroscopy to study environmental samples continue to increase. The ability of FTIR and Raman spectroscopies to provide complementary information for organic and inorganic materials makes them ideal approaches for soil science research. In addition, the ability to conduct in situ, real time, vibrational spectroscopy experiments to probe biogeochemical processes at mineral interfaces offers unique and versatile methodologies for revealing a myriad of soil chemical phenomena. This review provides a comprehensive overview of vibrational spectroscopy techniques and highlights many of the applications of their use in soil chemistry research.


      PubDate: 2014-06-18T20:42:54Z
       
  • Contributors
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 126




      PubDate: 2014-06-18T20:42:54Z
       
  • Copyright
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 126




      PubDate: 2014-06-18T20:42:54Z
       
  • Front Matter
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 126




      PubDate: 2014-06-18T20:42:54Z
       
  • Advances in Agronomy
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 126




      PubDate: 2014-06-18T20:42:54Z
       
  • Chapter Four Fertilizer Intensification and Its Impacts in China's HHH
           Plains
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 125
      Author(s): Xiangbin Kong , Rattan Lal , Baoguo Li , Hongbin Liu , Kejiang Li , Guanglong Feng , Qingpu Zhang , Bangbang Zhang
      The accomplishment of China's food security by application of high rates of fertilizers has generated several controversies regarding the quality of soil and water resources. Thus, the objective of this chapter is to assess the effects and causes of the fertilizer intensification in the Huang Huai Hai (HHH) plains in China based on the data from five long-term experiments conducted over a period of 20 years, and those from the National Bureau of Statistics of China. The HHH region produces almost 60–80% of China's wheat and 35–40% of China's corn every year. The average increase in yield (kgha−1) between 1985 and 2009 ranged from 1582 to 5860 for wheat and 4492 to 5610 for corn. However, the average rates (kgha−1year−1) of fertilizer use are about 430 of N, 107 of P, and 17 of K. The results from five long-term experiments on sites representative the HHH indicated that fertilizer intensification resulted in an increasing trend of high input of nutrients→high SOM concentration→high yields of wheat (Triticum aestivum) and corn (Zea mays)→higher SOM concentration→higher rate of application of fertilizer in agroecosystems. These mechanisms motivated the farm households to apply higher rate of fertilizer to obtain higher and stable crop yields despite large uncertainties in crop production due to climate change and other risks. Important among future research needs are precision agriculture, soil test, micronutrients, and foliar applications, to enhance the use efficiency of fertilizers and reduce losses.


      PubDate: 2014-04-29T06:45:13Z
       
  • Chapter Three GlobalSoilMap Toward a Fine-Resolution Global Grid of Soil
           Properties
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 125
      Author(s): Dominique Arrouays , Michael G. Grundy , Alfred E. Hartemink , Jonathan W. Hempel , Gerard B.M. Heuvelink , S. Young Hong , Philippe Lagacherie , Glenn Lelyk , Alexander B. McBratney , Neil J. McKenzie , Maria d.L. Mendonca-Santos , Budiman Minasny , Luca Montanarella , Inakwu O.A. Odeh , Pedro A. Sanchez , James A. Thompson , Gan-Lin Zhang
      Soil scientists are being challenged to provide assessments of soil condition from local through to global scales. A particular issue is the need for estimates of the stores and fluxes in soils of water, carbon, nutrients, and solutes. This review outlines progress in the development and testing of GlobalSoilMap—a digital soil map that aims to provide a fine-resolution global grid of soil functional properties with estimates of their associated uncertainties. A range of methods can be used to generate the fine-resolution spatial estimates depending on the availability of existing soil surveys, environmental data, and point observations. The system has an explicit geometry for estimating point and block estimates of soil properties continuously down the soil profile. This geometry is necessary to ensure mass balance when stores and fluxes are computed. It also overcomes some limitations with existing systems for characterizing soil variation with depth. GlobalSoilMap has been designed to enable delivery of soil data via Web services. This review provides an overview of the system's technical specifications including the minimum data set. Examples from contrasting countries and environments are then presented to demonstrate the robustness of the technical specifications. GlobalSoilMap provides the means for supplying soil information in a format and resolution compatible with other fundamental data sets from remote sensing, terrain analysis, and other systems for mapping, monitoring, and forecasting biophysical processes. The initial research phase of the core project is nearing completion and attention is now shifting toward establishing the institutional and governance arrangements necessary to complete a full global coverage and maintaining the operational version of the GlobalSoilMap. This will be a grand and rewarding challenge for the soil science profession in the coming years.


      PubDate: 2014-04-29T06:45:13Z
       
  • Chapter Two Agronomic Biofortification of Cereal Grains with Iron and Zinc
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 125
      Author(s): Rajendra Prasad , Yashbir S. Shivay , Dinesh Kumar
      Iron and zinc deficiencies in human nutrition are widespread in developing Asian and African countries where cereal grains are the staple food. Effects are therefore underway to develop cereal genotypes with grains denser in Fe and Zn by traditional plant breeding or using genetic engineering techniques. This approach requires a long period and adequate funds. However, the products of genetic engineering are not well accepted in many countries. Also, there is a trade-off between yield and grain biofortification. Agronomic biofortification offers to achieve this without sacrificing on yield and with no problem of product acceptance. From the viewpoint of biofortification, foliar application has been reported to be better than the soil application of Fe and Zn, and for this purpose, chelated Fe and Zn fertilizers are better. When soil applied, water soluble sources of Zn are better. Soil application of Fe is not recommended. Agronomic biofortification depends upon management practices (tillage, water management, nutrient interactions), soil factors (amounts present, pH, mechanisms of Zn fixation other than pH), and plant factors (root characteristics, excretion of phytosiderophores and organic acids by roots, Zn utilization at the cellular level, translocation within plant and mechanisms of Zn accumulation in grain). Genetic and agronomic biofortification are complementary to each other. Once the genotypes having denser grains are developed, they will have to be adequately fertilized with Fe and Zn. However, much more research in agronomy, soil science, and plant physiology is needed to understand the complex soil–plant–management interaction under different agroecological conditions under which cereals are grown. The situation is more complex for rice, which is grown under flooded, upland, and intermediate water conditions.


      PubDate: 2014-04-29T06:45:13Z
       
  • Chapter One Advances in Using Oxygen Isotope Ratios of Phosphate to
           Understand Phosphorus Cycling in the Environment
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 125
      Author(s): Deb P. Jaisi , Ruth E. Blake
      Phosphorus (P) is universally recognized as an essential nutrient for all known forms of life and a key element in mediating between living and nonliving parts of the biosphere. Here, we provide a comprehensive review of the development of oxygen isotope methods of phosphate and application to understand the biogeochemical cycling of P. With the advent of robust analytical techniques able to accurately determine stable oxygen isotope ratios in phosphate (δ18OP) and the increased understanding of isotope effects from controlled process- or reaction-based studies, δ18OP values have been increasingly applied to identify sources and cycling of P in many natural environments. Because different sources have distinct isotopic compositions and various processes impart specific isotopic fractionation or produce distinct pathways of isotopic evolution, application of δ18OP values as a tracer for P in biogeochemical processes is expected to continue to expand as an exciting field of research in the future.


      PubDate: 2014-04-29T06:45:13Z
       
  • Preface
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 125
      Author(s): Donald L. Sparks



      PubDate: 2014-04-29T06:45:13Z
       
  • Contributors
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 125




      PubDate: 2014-04-29T06:45:13Z
       
  • Copyright
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 125




      PubDate: 2014-04-29T06:45:13Z
       
  • Series Page
    • Abstract: Publication date: 2014
      Source:Advances in Agronomy, Volume 125




      PubDate: 2014-04-29T06:45:13Z
       
 
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
 
About JournalTOCs
API
Help
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-2014