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Publisher: John Wiley and Sons   (Total: 1579 journals)

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Showing 1 - 200 of 1579 Journals sorted alphabetically
Abacus     Hybrid Journal   (Followers: 12, SJR: 0.48, h-index: 22)
About Campus     Hybrid Journal   (Followers: 5)
Academic Emergency Medicine     Hybrid Journal   (Followers: 65, SJR: 1.385, h-index: 91)
Accounting & Finance     Hybrid Journal   (Followers: 46, SJR: 0.547, h-index: 30)
ACEP NOW     Free   (Followers: 1)
Acta Anaesthesiologica Scandinavica     Hybrid Journal   (Followers: 51, SJR: 1.02, h-index: 88)
Acta Archaeologica     Hybrid Journal   (Followers: 153, SJR: 0.101, h-index: 9)
Acta Geologica Sinica (English Edition)     Hybrid Journal   (Followers: 3, SJR: 0.552, h-index: 41)
Acta Neurologica Scandinavica     Hybrid Journal   (Followers: 5, SJR: 1.203, h-index: 74)
Acta Obstetricia et Gynecologica Scandinavica     Hybrid Journal   (Followers: 15, SJR: 1.197, h-index: 81)
Acta Ophthalmologica     Hybrid Journal   (Followers: 5, SJR: 0.112, h-index: 1)
Acta Paediatrica     Hybrid Journal   (Followers: 56, SJR: 0.794, h-index: 88)
Acta Physiologica     Hybrid Journal   (Followers: 6, SJR: 1.69, h-index: 88)
Acta Polymerica     Hybrid Journal   (Followers: 9)
Acta Psychiatrica Scandinavica     Hybrid Journal   (Followers: 35, SJR: 2.518, h-index: 113)
Acta Zoologica     Hybrid Journal   (Followers: 6, SJR: 0.459, h-index: 29)
Acute Medicine & Surgery     Hybrid Journal   (Followers: 4)
Addiction     Hybrid Journal   (Followers: 35, SJR: 2.086, h-index: 143)
Addiction Biology     Hybrid Journal   (Followers: 13, SJR: 2.091, h-index: 57)
Adultspan J.     Hybrid Journal   (SJR: 0.127, h-index: 4)
Advanced Energy Materials     Hybrid Journal   (Followers: 26, SJR: 6.411, h-index: 86)
Advanced Engineering Materials     Hybrid Journal   (Followers: 26, SJR: 0.81, h-index: 81)
Advanced Functional Materials     Hybrid Journal   (Followers: 50, SJR: 5.21, h-index: 203)
Advanced Healthcare Materials     Hybrid Journal   (Followers: 13, SJR: 0.232, h-index: 7)
Advanced Materials     Hybrid Journal   (Followers: 258, SJR: 9.021, h-index: 345)
Advanced Materials Interfaces     Hybrid Journal   (Followers: 6, SJR: 1.177, h-index: 10)
Advanced Optical Materials     Hybrid Journal   (Followers: 5, SJR: 2.488, h-index: 21)
Advanced Science     Open Access   (Followers: 5)
Advanced Synthesis & Catalysis     Hybrid Journal   (Followers: 17, SJR: 2.729, h-index: 121)
Advances in Polymer Technology     Hybrid Journal   (Followers: 13, SJR: 0.344, h-index: 31)
Africa Confidential     Hybrid Journal   (Followers: 19)
Africa Research Bulletin: Economic, Financial and Technical Series     Hybrid Journal   (Followers: 12)
Africa Research Bulletin: Political, Social and Cultural Series     Hybrid Journal   (Followers: 9)
African Development Review     Hybrid Journal   (Followers: 34, SJR: 0.275, h-index: 17)
African J. of Ecology     Hybrid Journal   (Followers: 15, SJR: 0.477, h-index: 39)
Aggressive Behavior     Hybrid Journal   (Followers: 15, SJR: 1.391, h-index: 66)
Aging Cell     Open Access   (Followers: 10, SJR: 4.374, h-index: 95)
Agribusiness : an Intl. J.     Hybrid Journal   (Followers: 6, SJR: 0.627, h-index: 14)
Agricultural and Forest Entomology     Hybrid Journal   (Followers: 15, SJR: 0.925, h-index: 43)
Agricultural Economics     Hybrid Journal   (Followers: 45, SJR: 1.099, h-index: 51)
AIChE J.     Hybrid Journal   (Followers: 30, SJR: 1.122, h-index: 120)
Alcoholism and Drug Abuse Weekly     Hybrid Journal   (Followers: 7)
Alcoholism Clinical and Experimental Research     Hybrid Journal   (Followers: 7, SJR: 1.416, h-index: 125)
Alimentary Pharmacology & Therapeutics     Hybrid Journal   (Followers: 33, SJR: 2.833, h-index: 138)
Alimentary Pharmacology & Therapeutics Symposium Series     Hybrid Journal   (Followers: 3)
Allergy     Hybrid Journal   (Followers: 50, SJR: 3.048, h-index: 129)
Alternatives to the High Cost of Litigation     Hybrid Journal   (Followers: 3)
American Anthropologist     Hybrid Journal   (Followers: 139, SJR: 0.951, h-index: 61)
American Business Law J.     Hybrid Journal   (Followers: 24, SJR: 0.205, h-index: 17)
American Ethnologist     Hybrid Journal   (Followers: 90, SJR: 2.325, h-index: 51)
American J. of Economics and Sociology     Hybrid Journal   (Followers: 28, SJR: 0.211, h-index: 26)
American J. of Hematology     Hybrid Journal   (Followers: 33, SJR: 1.761, h-index: 77)
American J. of Human Biology     Hybrid Journal   (Followers: 12, SJR: 1.018, h-index: 58)
American J. of Industrial Medicine     Hybrid Journal   (Followers: 16, SJR: 0.993, h-index: 85)
American J. of Medical Genetics Part A     Hybrid Journal   (Followers: 16, SJR: 1.115, h-index: 61)
American J. of Medical Genetics Part B: Neuropsychiatric Genetics     Hybrid Journal   (Followers: 4, SJR: 1.771, h-index: 107)
American J. of Medical Genetics Part C: Seminars in Medical Genetics     Partially Free   (Followers: 6, SJR: 2.315, h-index: 79)
American J. of Physical Anthropology     Hybrid Journal   (Followers: 37, SJR: 1.41, h-index: 88)
American J. of Political Science     Hybrid Journal   (Followers: 271, SJR: 5.101, h-index: 114)
American J. of Primatology     Hybrid Journal   (Followers: 15, SJR: 1.197, h-index: 63)
American J. of Reproductive Immunology     Hybrid Journal   (Followers: 3, SJR: 1.347, h-index: 75)
American J. of Transplantation     Hybrid Journal   (Followers: 17, SJR: 2.792, h-index: 140)
American J. on Addictions     Hybrid Journal   (Followers: 9, SJR: 0.843, h-index: 57)
Anaesthesia     Hybrid Journal   (Followers: 132, SJR: 1.404, h-index: 88)
Analyses of Social Issues and Public Policy     Hybrid Journal   (Followers: 10, SJR: 0.397, h-index: 18)
Analytic Philosophy     Hybrid Journal   (Followers: 16)
Anatomia, Histologia, Embryologia: J. of Veterinary Medicine Series C     Hybrid Journal   (Followers: 3, SJR: 0.295, h-index: 27)
Anatomical Sciences Education     Hybrid Journal   (Followers: 1, SJR: 0.633, h-index: 24)
Andrologia     Hybrid Journal   (Followers: 2, SJR: 0.528, h-index: 45)
Andrology     Hybrid Journal   (Followers: 2, SJR: 0.979, h-index: 14)
Angewandte Chemie     Hybrid Journal   (Followers: 172)
Angewandte Chemie Intl. Edition     Hybrid Journal   (Followers: 216, SJR: 6.229, h-index: 397)
Animal Conservation     Hybrid Journal   (Followers: 38, SJR: 1.576, h-index: 62)
Animal Genetics     Hybrid Journal   (Followers: 8, SJR: 0.957, h-index: 67)
Animal Science J.     Hybrid Journal   (Followers: 6, SJR: 0.569, h-index: 24)
Annalen der Physik     Hybrid Journal   (Followers: 5, SJR: 1.46, h-index: 40)
Annals of Anthropological Practice     Partially Free   (Followers: 2, SJR: 0.187, h-index: 5)
Annals of Applied Biology     Hybrid Journal   (Followers: 7, SJR: 0.816, h-index: 56)
Annals of Clinical and Translational Neurology     Open Access   (Followers: 1)
Annals of Human Genetics     Hybrid Journal   (Followers: 9, SJR: 1.191, h-index: 67)
Annals of Neurology     Hybrid Journal   (Followers: 47, SJR: 5.584, h-index: 241)
Annals of Noninvasive Electrocardiology     Hybrid Journal   (Followers: 2, SJR: 0.531, h-index: 38)
Annals of Public and Cooperative Economics     Hybrid Journal   (Followers: 9, SJR: 0.336, h-index: 23)
Annals of the New York Academy of Sciences     Hybrid Journal   (Followers: 5, SJR: 2.389, h-index: 189)
Annual Bulletin of Historical Literature     Hybrid Journal   (Followers: 13)
Annual Review of Information Science and Technology     Hybrid Journal   (Followers: 14)
Anthropology & Education Quarterly     Hybrid Journal   (Followers: 25, SJR: 0.72, h-index: 31)
Anthropology & Humanism     Hybrid Journal   (Followers: 17, SJR: 0.137, h-index: 3)
Anthropology News     Hybrid Journal   (Followers: 15)
Anthropology of Consciousness     Hybrid Journal   (Followers: 11, SJR: 0.172, h-index: 5)
Anthropology of Work Review     Hybrid Journal   (Followers: 11, SJR: 0.256, h-index: 5)
Anthropology Today     Hybrid Journal   (Followers: 90, SJR: 0.545, h-index: 15)
Antipode     Hybrid Journal   (Followers: 47, SJR: 2.212, h-index: 69)
Anz J. of Surgery     Hybrid Journal   (Followers: 7, SJR: 0.432, h-index: 59)
Anzeiger für Schädlingskunde     Hybrid Journal   (Followers: 1)
Apmis     Hybrid Journal   (Followers: 1, SJR: 0.855, h-index: 73)
Applied Cognitive Psychology     Hybrid Journal   (Followers: 69, SJR: 0.754, h-index: 69)
Applied Organometallic Chemistry     Hybrid Journal   (Followers: 7, SJR: 0.632, h-index: 58)
Applied Psychology     Hybrid Journal   (Followers: 145, SJR: 1.023, h-index: 64)
Applied Psychology: Health and Well-Being     Hybrid Journal   (Followers: 49, SJR: 0.868, h-index: 13)
Applied Stochastic Models in Business and Industry     Hybrid Journal   (Followers: 5, SJR: 0.613, h-index: 24)
Aquaculture Nutrition     Hybrid Journal   (Followers: 14, SJR: 1.025, h-index: 55)
Aquaculture Research     Hybrid Journal   (Followers: 31, SJR: 0.807, h-index: 60)
Aquatic Conservation Marine and Freshwater Ecosystems     Hybrid Journal   (Followers: 36, SJR: 1.047, h-index: 57)
Arabian Archaeology and Epigraphy     Hybrid Journal   (Followers: 11, SJR: 0.453, h-index: 11)
Archaeological Prospection     Hybrid Journal   (Followers: 12, SJR: 0.922, h-index: 21)
Archaeology in Oceania     Hybrid Journal   (Followers: 13, SJR: 0.745, h-index: 18)
Archaeometry     Hybrid Journal   (Followers: 27, SJR: 0.809, h-index: 48)
Archeological Papers of The American Anthropological Association     Hybrid Journal   (Followers: 15, SJR: 0.156, h-index: 2)
Architectural Design     Hybrid Journal   (Followers: 25, SJR: 0.261, h-index: 9)
Archiv der Pharmazie     Hybrid Journal   (Followers: 4, SJR: 0.628, h-index: 43)
Archives of Drug Information     Hybrid Journal   (Followers: 4)
Archives of Insect Biochemistry and Physiology     Hybrid Journal   (SJR: 0.768, h-index: 54)
Area     Hybrid Journal   (Followers: 12, SJR: 0.938, h-index: 57)
Art History     Hybrid Journal   (Followers: 238, SJR: 0.153, h-index: 13)
Arthritis & Rheumatology     Hybrid Journal   (Followers: 51, SJR: 1.984, h-index: 20)
Arthritis Care & Research     Hybrid Journal   (Followers: 27, SJR: 2.256, h-index: 114)
Artificial Organs     Hybrid Journal   (Followers: 1, SJR: 0.872, h-index: 60)
ASHE Higher Education Reports     Hybrid Journal   (Followers: 14)
Asia & the Pacific Policy Studies     Open Access   (Followers: 15)
Asia Pacific J. of Human Resources     Hybrid Journal   (Followers: 313, SJR: 0.494, h-index: 19)
Asia Pacific Viewpoint     Hybrid Journal   (Followers: 1, SJR: 0.616, h-index: 26)
Asia-Pacific J. of Chemical Engineering     Hybrid Journal   (Followers: 8, SJR: 0.345, h-index: 20)
Asia-pacific J. of Clinical Oncology     Hybrid Journal   (Followers: 6, SJR: 0.554, h-index: 14)
Asia-Pacific J. of Financial Studies     Hybrid Journal   (SJR: 0.241, h-index: 7)
Asia-Pacific Psychiatry     Hybrid Journal   (Followers: 4, SJR: 0.377, h-index: 7)
Asian Economic J.     Hybrid Journal   (Followers: 8, SJR: 0.234, h-index: 21)
Asian Economic Policy Review     Hybrid Journal   (Followers: 4, SJR: 0.196, h-index: 12)
Asian J. of Control     Hybrid Journal   (SJR: 0.862, h-index: 34)
Asian J. of Endoscopic Surgery     Hybrid Journal   (SJR: 0.394, h-index: 7)
Asian J. of Organic Chemistry     Hybrid Journal   (Followers: 5, SJR: 1.443, h-index: 19)
Asian J. of Social Psychology     Hybrid Journal   (Followers: 5, SJR: 0.665, h-index: 37)
Asian Politics and Policy     Hybrid Journal   (Followers: 12, SJR: 0.207, h-index: 7)
Asian Social Work and Policy Review     Hybrid Journal   (Followers: 5, SJR: 0.318, h-index: 5)
Asian-pacific Economic Literature     Hybrid Journal   (Followers: 5, SJR: 0.168, h-index: 15)
Assessment Update     Hybrid Journal   (Followers: 4)
Astronomische Nachrichten     Hybrid Journal   (Followers: 2, SJR: 0.701, h-index: 40)
Atmospheric Science Letters     Open Access   (Followers: 29, SJR: 1.332, h-index: 27)
Austral Ecology     Hybrid Journal   (Followers: 14, SJR: 1.095, h-index: 66)
Austral Entomology     Hybrid Journal   (Followers: 9, SJR: 0.524, h-index: 28)
Australasian J. of Dermatology     Hybrid Journal   (Followers: 8, SJR: 0.714, h-index: 40)
Australasian J. On Ageing     Hybrid Journal   (Followers: 7, SJR: 0.39, h-index: 22)
Australian & New Zealand J. of Statistics     Hybrid Journal   (Followers: 13, SJR: 0.275, h-index: 28)
Australian Accounting Review     Hybrid Journal   (Followers: 4, SJR: 0.709, h-index: 14)
Australian and New Zealand J. of Family Therapy (ANZJFT)     Hybrid Journal   (Followers: 3, SJR: 0.382, h-index: 12)
Australian and New Zealand J. of Obstetrics and Gynaecology     Hybrid Journal   (Followers: 46, SJR: 0.814, h-index: 49)
Australian and New Zealand J. of Public Health     Hybrid Journal   (Followers: 11, SJR: 0.82, h-index: 62)
Australian Dental J.     Hybrid Journal   (Followers: 7, SJR: 0.482, h-index: 46)
Australian Economic History Review     Hybrid Journal   (Followers: 4, SJR: 0.171, h-index: 12)
Australian Economic Papers     Hybrid Journal   (Followers: 29, SJR: 0.23, h-index: 9)
Australian Economic Review     Hybrid Journal   (Followers: 6, SJR: 0.357, h-index: 21)
Australian Endodontic J.     Hybrid Journal   (Followers: 3, SJR: 0.513, h-index: 24)
Australian J. of Agricultural and Resource Economics     Hybrid Journal   (Followers: 3, SJR: 0.765, h-index: 36)
Australian J. of Grape and Wine Research     Hybrid Journal   (Followers: 5, SJR: 0.879, h-index: 56)
Australian J. of Politics & History     Hybrid Journal   (Followers: 14, SJR: 0.203, h-index: 14)
Australian J. of Psychology     Hybrid Journal   (Followers: 18, SJR: 0.384, h-index: 30)
Australian J. of Public Administration     Hybrid Journal   (Followers: 407, SJR: 0.418, h-index: 29)
Australian J. of Rural Health     Hybrid Journal   (Followers: 5, SJR: 0.43, h-index: 34)
Australian Occupational Therapy J.     Hybrid Journal   (Followers: 71, SJR: 0.59, h-index: 29)
Australian Psychologist     Hybrid Journal   (Followers: 12, SJR: 0.331, h-index: 31)
Australian Veterinary J.     Hybrid Journal   (Followers: 19, SJR: 0.459, h-index: 45)
Autism Research     Hybrid Journal   (Followers: 32, SJR: 2.126, h-index: 39)
Autonomic & Autacoid Pharmacology     Hybrid Journal   (SJR: 0.371, h-index: 29)
Banks in Insurance Report     Hybrid Journal   (Followers: 1)
Basic & Clinical Pharmacology & Toxicology     Hybrid Journal   (Followers: 10, SJR: 0.539, h-index: 70)
Basic and Applied Pathology     Open Access   (Followers: 2, SJR: 0.113, h-index: 4)
Basin Research     Hybrid Journal   (Followers: 5, SJR: 1.54, h-index: 60)
Bauphysik     Hybrid Journal   (Followers: 2, SJR: 0.194, h-index: 5)
Bauregelliste A, Bauregelliste B Und Liste C     Hybrid Journal  
Bautechnik     Hybrid Journal   (Followers: 1, SJR: 0.321, h-index: 11)
Behavioral Interventions     Hybrid Journal   (Followers: 9, SJR: 0.297, h-index: 23)
Behavioral Sciences & the Law     Hybrid Journal   (Followers: 24, SJR: 0.736, h-index: 57)
Berichte Zur Wissenschaftsgeschichte     Hybrid Journal   (Followers: 9, SJR: 0.11, h-index: 5)
Beton- und Stahlbetonbau     Hybrid Journal   (Followers: 2, SJR: 0.493, h-index: 14)
Biochemistry and Molecular Biology Education     Hybrid Journal   (Followers: 6, SJR: 0.311, h-index: 26)
Bioelectromagnetics     Hybrid Journal   (Followers: 1, SJR: 0.568, h-index: 64)
Bioengineering & Translational Medicine     Open Access  
BioEssays     Hybrid Journal   (Followers: 10, SJR: 3.104, h-index: 155)
Bioethics     Hybrid Journal   (Followers: 14, SJR: 0.686, h-index: 39)
Biofuels, Bioproducts and Biorefining     Hybrid Journal   (Followers: 1, SJR: 1.725, h-index: 56)
Biological J. of the Linnean Society     Hybrid Journal   (Followers: 16, SJR: 1.172, h-index: 90)
Biological Reviews     Hybrid Journal   (Followers: 3, SJR: 6.469, h-index: 114)
Biologie in Unserer Zeit (Biuz)     Hybrid Journal   (Followers: 42, SJR: 0.12, h-index: 1)
Biology of the Cell     Full-text available via subscription   (Followers: 9, SJR: 1.812, h-index: 69)
Biomedical Chromatography     Hybrid Journal   (Followers: 6, SJR: 0.572, h-index: 49)
Biometrical J.     Hybrid Journal   (Followers: 5, SJR: 0.784, h-index: 44)
Biometrics     Hybrid Journal   (Followers: 36, SJR: 1.906, h-index: 96)
Biopharmaceutics and Drug Disposition     Hybrid Journal   (Followers: 10, SJR: 0.715, h-index: 44)
Biopolymers     Hybrid Journal   (Followers: 18, SJR: 1.199, h-index: 104)
Biotechnology and Applied Biochemistry     Hybrid Journal   (Followers: 45, SJR: 0.415, h-index: 55)
Biotechnology and Bioengineering     Hybrid Journal   (Followers: 180, SJR: 1.633, h-index: 146)
Biotechnology J.     Hybrid Journal   (Followers: 14, SJR: 1.185, h-index: 51)
Biotechnology Progress     Hybrid Journal   (Followers: 39, SJR: 0.736, h-index: 101)
Biotropica     Hybrid Journal   (Followers: 20, SJR: 1.374, h-index: 71)
Bipolar Disorders     Hybrid Journal   (Followers: 9, SJR: 2.592, h-index: 100)
Birth     Hybrid Journal   (Followers: 37, SJR: 0.763, h-index: 64)
Birth Defects Research Part A : Clinical and Molecular Teratology     Hybrid Journal   (Followers: 2, SJR: 0.727, h-index: 77)
Birth Defects Research Part B: Developmental and Reproductive Toxicology     Hybrid Journal   (Followers: 5, SJR: 0.468, h-index: 47)
Birth Defects Research Part C : Embryo Today : Reviews     Hybrid Journal   (SJR: 1.513, h-index: 55)
BJOG : An Intl. J. of Obstetrics and Gynaecology     Partially Free   (Followers: 231, SJR: 2.083, h-index: 125)

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Journal Cover Annals of Applied Biology
  [SJR: 0.816]   [H-I: 56]   [7 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0003-4746 - ISSN (Online) 1744-7348
   Published by John Wiley and Sons Homepage  [1579 journals]
  • Antioxidant system is essential to increase drought tolerance of sugarcane
    • Authors: R.D. Vilela; B.K.L. Bezerra, A. Froehlich, L. Endres
      Abstract: Drought is one of the main factors affecting the productivity of agricultural crops, and plants respond to such stress by activating various physiological and biochemical mechanisms against dehydration. The present study investigated two varieties of sugarcane (Saccharum spp.) with contrasting responses to drought (RB867515, more tolerant; and RB855536, less tolerant) and subjected them to progressive drought conditions (2, 4, 6 and 8 days) followed by rehydration. Drought caused a decrease in water potential (ψw) and osmotic potential (ψos) in the leaves, which recovered to normal levels after rehydration only up to the fourth day of drought. Water stress changed the carbon metabolism of leaves by reducing starch and sucrose contents and increasing glucose and fructose contents in both varieties. Water deficit caused a significant reduction in the maximum quantum efficiency of photosystem II (Fv/Fm) and effective quantum yield (ΦPSII) in both varieties; however, RB867515 recovered faster after rehydration. Under water stress, the more tolerant variety RB867515 exhibited increased activity of the antioxidant enzymes catalase, ascorbate peroxidase and superoxide dismutase compared with the RB855536 variety. The results suggest that RB867515 is more tolerant to drought conditions because of a more efficient antioxidant system, which results in reduced photosynthesis photoinhibition during water stress, thus revealing itself as a potential physiological marker for drought tolerance studies.Two varieties of sugarcane (Saccharum spp.) with contrasting responses to drought (RB867515, more tolerant; and RB855536, less tolerant) were subjected to progressive drought conditions (2, 4, 6 and 8 days) followed by rehydration. Several physiological parameters were measured: leaf water potential and osmotic potential; leaf carbon metabolism; maximum and effective PSII quantum yield; and antioxidant enzymes. The results suggest that RB867515 is more tolerant to drought conditions because of a more efficient antioxidant system, which results in reduced photosynthesis photoinhibition during water stress, thus revealing itself as a potential physiological marker for drought tolerance studies.
      PubDate: 2017-10-11T21:25:34.728509-05:
      DOI: 10.1111/aab.12387
       
  • Effect of tillage, subsidiary crops and fertilisation on plant-parasitic
           nematodes in a range of agro-environmental conditions within Europe
    • Authors: J.H. Schmidt; G. Bergkvist, E. Campiglia, E. Radicetti, R.A. Wittwer, M.R. Finckh, J. Hallmann
      Abstract: The overall goal in nematode management is to develop sustainable systems where nematode populations are kept under the economic damage threshold. Conservation tillage and subsidiary crops, applied as cover crops and living mulches, generally improve soil health by increasing soil organic matter content and stimulating soil microbial activity. However, more permanent crop and weed cover associated with subsidiary crops and noninversion tillage, respectively, may benefit plant-parasitic nematodes with broad host spectra such as Meloidogyne and Pratylenchus. These genera are major constraints to many field crops throughout Europe and there is a need to identify effective and reliable management options that can be applied to avoid excessive infestations. The dynamics of the indigenous fauna of plant-parasitic nematodes were studied in eight coordinated multi-environment field experiments (MEEs) under four agro-environmental conditions in Europe (Continental, Nemoral, Atlantic North and Mediterranean North). The MEEs consisted of a 2-year sequence of wheat combined with a living mulch or subsequent cover crops and second main crops maize, potatoes or tomatoes depending on site. Additionally, the effects of inversion tillage using the plough were compared with various forms of conservation tillage (no-tillage, shallow and deep noninversion tillage). Overall, Helicotylenchus, Paratylenchus, Pratylenchus and Tylenchorhynchus were the most frequent genera across sites while Meloidogyne occurred only in Germany at very low densities. During the wheat–maize sequences in Switzerland, the populations of Pratylenchus increased from 63 to 146 nematodes per 100 mL soil and Helicotylenchus from 233 to 632 nematodes per 100 mL soil. The effects of tillage on plant-parasitic nematodes were generally minor, although no tillage in Italy supported higher densities of Pratylenchus (184 nematodes per 100 mL soil) than inversion tillage (59 nematodes per 100 mL soil). Furthermore, Pratylenchus densities were 160 nematodes per 100 mL soil when leguminous subsidiary crops were grown, 122 nematodes per 100 mL soil in the green fallow and 84 nematodes per 100 mL soil after growing black oat (Avena strigosa) or oilseed radish (Raphanus sativus). The differences were greatest in Italy, in a sandy soil with low organic matter. Application of compost or nitrogen fertiliser had no consistent effects on plant-parasitic nematodes. We conclude that crop rotations including specific subsidiary crops are prominent factors affecting the indigenous nematode community, while tillage and fertiliser are of lower importance.The effects of tillage on plant-parasitic nematodes were generally minor, although no tillage in Italy supported higher densities of Pratylenchus (184 nematodes per 100 ml soil) than inversion tillage (59 nematodes per 100 ml soil). Pratylenchus densities were 160 nematodes per 100 ml soil when leguminous subsidiary crops were grown, 122 nematodes per 100 ml soil in the green fallow, and 84 nematodes per 100 ml soil after growing black oat (Avena strigosa) or oilseed radish (Raphanus sativus). Crop rotations including specific subsidiary crops are therefore prominent factors affecting indigenous nematode communities, while tillage and fertilizer are of lower importance.
      PubDate: 2017-10-04T01:45:31.246357-05:
      DOI: 10.1111/aab.12389
       
  • Comparative analysis of core collection sampling methods for mandarin
           germplasm based on molecular and phenotypic data
    • Authors: A. Garcia-Lor; F. Luro, P. Ollitrault, L. Navarro
      Abstract: Gene banks have been established to conserve the genetic diversity of crop species. Large germplasm collections lead to management problems (space, maintenance costs, etc.), especially in collections involving species with recalcitrant seeds that must be maintained as growing plants. Core collections (CCs) are thus developed to reduce the size of large germplasm collections while keeping the maximum variability. This also facilitates fine phenotypic evaluation. In this study, several software packages (DARwin, PowerMarker and MSTRAT) and methods (Max length subtree, M strategy, simulated annealing and MinSD) were compared to define a mandarin (Citrus reticulata) CC. One hundred and sixty-seven accessions were sampled from two germplasm collections, which were genotyped with 50 SSR, 24 InDel and 68 single nucleotide polymorphism markers. All the CC obtained were tested for the maintenance of the genetic variability parameters (Ho and He) of the initial collection, the level of linkage disequilibrium (LD) and the phenotypic diversity retention. The Max length subtree function from DARWin seemed to be the most appropriate method for establishing a CC in C. reticulata. It maintained 96.82% of the allelic richness and 17.96% of the size of the initial collection with only 30 accessions. Besides it did not increase the LD (r2 value) of the initial collection and retained the vast majority of the phenotypic variability. However, a CC with 70 accessions would be more helpful for genetic association studies.Comparative results of the core collection sampling methods in the two sizes selected (χ2, P < 0.05). Germplasm collections are established to maintain the genetic diversity of the crops. When they are huge and are species with recalcitrant seeds as citrus, their maintenance, costs, space and so on become a problem. To reduce their size, but maintaining their diversity, core collections are being developed.
      PubDate: 2017-10-01T22:40:27.831975-05:
      DOI: 10.1111/aab.12376
       
  • Phenological growth stages of mulberry tree (Morus sp.) codification and
           description according to the BBCH scale
    • Authors: E.M. Sánchez-Salcedo; J.J. Martínez-Nicolás, Fca. Hernández
      Abstract: Recently, mulberry fruits have increased rapidly the production and consumption, due to its high levels of bioactive compounds, excellent taste and nutritional value. Nevertheless there is poorly information about its phenology. In the present study, the different phenological growth stages of mulberry are characterised according to the BBCH (Biologische Bundesanstalt, Bundessortenamt Chemische Industrie) scale. Eight of the 10 principal developmental stages from BBCH scale were described for Morus sp., starting at bud development (stage 0) and ending at the senescence and beginning of the rest period (stage 9). The BBCH code for this species provides a consensual unified approach for standardisation of phenological stages in mulberry, moreover to facilitate agronomic practices.Phenology of the mulberry tree
      PubDate: 2017-10-01T21:56:06.472457-05:
      DOI: 10.1111/aab.12386
       
  • Antagonism between Byssochlamys spectabilis (anamorph Paecilomyces
           variotii) and plant pathogens: Involvement of the bioactive compounds
           produced by the endophyte
    • Authors: S. Rodrigo; O. Santamaria, S. Halecker, S. Lledó, M. Stadler
      Abstract: Fungal endophytes can be part of the defensive system of plants against multiple pathogens by competing for resources, hyperparasitism or producing bioactive compounds with antimicrobial properties. There is an ever-increasing interest for obtaining new and environmentally friendly products to use in the fight against pathogens. With this purpose, Byssochlamys spectabilis (anamorph Paecilomyces variotii), which is a fungal species that commonly occurs, was evaluated as an antagonistic organism towards three phytopathogens (Biscogniauxia mediterranea, Fusarium moniliforme and Phytophthora cinnamomi). First, an in vitro experiment was designed to test the effect that the endophyte filtrate had on the three pathogens. The endophyte filtrate decreased the radius growth rate of F. moniliforme by nearly 10%. Consequently, the antagonism between B. spectabilis and F. moniliforme was evaluated in Lolium rigidum plants under greenhouse conditions by means of co-inoculations. The endophyte produced a decrease of 50–75% in the disease severity caused by the pathogen in the earliest infection stages. Crude extracts of B. spectabilis were obtained to determine the secondary metabolites responsible for such an effect. The bioactivity-guided chromatography and HPLC-MS (high performance liquid chromatography coupled with mass spectrometry) of the active fraction suggested that the antibiotic activity was caused by viriditoxin. In conclusion, the fungal endophyte B. spectabilis and/or its bioactive compounds showed antagonism towards several phytopathogens and deserves further study to investigate its actual potential for use as a biocontrol agent.The fungal endophyte Byssochlamys spectabilis (anamorph Paecilomyces variotii) showed antagonism towards phytopathogens in vitro and in Lolium rigidum plants. The antibiotic activity seemed to be caused by the secondary metabolite viriditoxin produced by the endophyte
      PubDate: 2017-09-29T10:59:12.424241-05:
      DOI: 10.1111/aab.12388
       
  • How do caterpillars cope with xenobiotics' The case of Mythimna
           unipuncta, a species with low susceptibility to Bt
    • Authors: C. López; P. Muñoz, M. Pérez-Hedo, M. Moralejo, M. Eizaguirre
      Abstract: Mythimna unipuncta is a species with low susceptibility to the Bacillus thuringiensis (Bt) toxin, and this insect occasionally causes devastating damage to maize. In the study region, M. unipuncta-developed larvae were observed moving from a non-Bt crop to a nearby Bt crop. Although the first response of many caterpillars to xenobiotics, such as the Bt toxin, is to reduce food intake and prolong development, few studies have focused on the causes and consequences of this response in terms of resistance evolution. To clarify the causes of this response, this work compared changes in the feeding behaviour, cytochrome P450 expression and juvenile hormone titre during the last larval instar of M. unipuncta after Bt ingestion. Four P450 enzymes related to the xenobiotic metabolism of the CYP9 and CYP6 families were identified. Developed larvae fed the Bt diet reduced their food intake and CYP9 expression, experienced prolonged development and presented an altered juvenile hormone balance. The CYP9s were not increased in the larvae that consumed Bt, as previously expected, although their highest expression was observed when larval feeding increased. The high recovery capacity of the larvae contributed to their development when they were fed a non-Bt diet. The efficiency of responses that act jointly as a defence mechanism against Bt might favour the development of field resistance to the toxin. Therefore, these responses should be further investigated for resistance management programmes.How do caterpillars cope with xenobiotics' The case of Mythimna unipuncta, a species with low susceptibility to Bt
      PubDate: 2017-09-21T23:26:19.083633-05:
      DOI: 10.1111/aab.12380
       
  • Grafting to manage infections of top stunting and necrogenic strains of
           cucumber mosaic virus in tomato
    • Authors: R. Spanò; D. Gallitelli, T. Mascia
      Abstract: Cucumber mosaic virus (CMV) lists among the most important etiological agents of tomato diseases. Some isolates of CMV function as helper virus for replication, encapsidation and transmission of satellite RNAs (satRNA), which may exacerbate symptoms induced by CMV in certain hosts. Outbreaks of CMV strains supporting hypervirulent variants of satRNAs are recurrent in tomato with devastating effects on crop production and efficient control measures are still unavailable. In this study, we examined the dynamics of infection of the CMV strains tomato top stunting (TTS) and 77 supporting replication of satRNA variants that codetermine top stunting (TTS-satRNA) and necrotic (77-satRNA) phenotypes in two tomato cultivars denoted Solanum lycopersicum Manduria (Sl-Ma) and S. lycopersicum UC82 (Sl-UC). Sl-Ma but not Sl-UC recovered from disease symptoms induced by CMV-TTS while both the cultivars succumbed to the infection of CMV-77 and its necrogenic satRNA. Ability to recover of the Sl-Ma plants was transmitted by grafting to the susceptible genotype Sl-UC. More interestingly, recovery was observed also against the challenge inoculation of CMV plus 77-satRNA in plants grafted on Sl-Ma and in self-grafted plants of both the Sl-Ma and Sl-UC cultivars. Analysis of small RNAs and genes of the defence plant response based on RNA interference (RNAi) suggested that RNAi is involved in the recovery of Sl-Ma against CMV with hypervirulent satRNAs and in scions grafted on this rootstock. The response of Sl-Ma to the inoculation of CMV-77 plus 77-satRNA was compared with that of the transgenic tomato line S. lycopersicum transgenic line UCTC5.9.2 that expresses constitutively the benign variant of the satRNA denoted Tfn-satRNA. Comparative analysis suggested that the response may operate via similar mechanisms, which involve RNAi, the graft and the presence of the satRNA.Tomato plants grafted on Sl-Ma tomato cultivar recovered from severe symptoms induced by cucumber mosaic virus (CMV) strains supporting hypervirulent satRNAs like those that codetermine stunting (TTS-satRNA) and necrotic (77-satRNA) phenotypes in tomato. The response of Sl-Ma to the inoculation of CMV-77 plus 77-satRNA parallels that of the transgenic tomato line Sl-UCTC that expresses constitutively the benign variant of the satRNA denoted Tfn-satRNA. On the whole, results suggest that in the two tomato genotypes the response may operate via similar mechanisms, which involve RNAi, the graft and the presence of the satRNA.
      PubDate: 2017-09-21T03:15:54.516118-05:
      DOI: 10.1111/aab.12382
       
  • Incidence and control of black spot syndrome of tiger nut
    • Authors: D. Alvares; C. Armero, A. Forte, J. Serra, L. Galipienso, L. Rubio
      Abstract: Tiger nut (Cyperus esculentum) is a very profitable crop in Valencia, Spain, but in the last years, part of the harvested tubers presents black spots in the skin making them unmarketable. Surveys performed in two consecutive years showed that about 10% of the tubers were severely affected by the black spot syndrome whose aetiology is unknown. Disease control procedures based on selection of tubers used as seed (seed tubers) or treatment with hot-water and/or chemicals were assayed in greenhouse. These assays showed that that this syndrome had a negative impact on the germination rate, tuber size and yield. Selection of asymptomatic seed tubers reduced drastically the incidence of the black spot syndrome with respect to using seed tubers with severe symptoms (selection of healthy seed tubers was not possible because the causal agent is undetermined). Thermal treatment of seed tubers with severe symptoms reduced the number of unmarketable harvested tubers by half but was detrimental for the germination. Chemical treatments of seed tubers with severe symptoms decreased the incidence of the black spot syndrome about 40% for sodium hypochlorite and about 10% for hydrochloric acid, trisodium phosphate and the fungicide trioxystrobin.The black spot syndrome, of unknown etiology, causes considerable economical losses in tiger nut crops in Eastern Spain. Our results showed that the best method to control this syndrome was the selection of asymptomatic tubers used as seed, which showed lower incidence of the black spot syndrome and an improvement in the germination rate and the yield of marketable tubers. Thermal and chemical treatments also reduced the incidence of this syndrome. The figure shows the comparison of harvested tubers of tiger nut in pots in greenhouse from seed tubers with severe symptoms of the black spot syndrome (S) and from asymptomatic seed tubers (A). Time-course incidence of the black spot syndrome (proportion of unmarketable tubers, showing severe symptoms), germination rate (proportion of germinated seed tubers), yield of marketable tubers (weight per pot). Dots represent posterior medians and vertical segments credible intervals at 95%.
      PubDate: 2017-09-13T00:45:32.786211-05:
      DOI: 10.1111/aab.12384
       
  • Phenological behaviour of Parthenium hysterophorus in response to climatic
           variations according to the extended BBCH scale
    • Authors: A. Kaur; D.R. Batish, S. Kaur, H.P. Singh, R.K. Kohli
      Abstract: Considering the importance of ecological and biological traits in imparting invasive success to the alien species, the phenological behaviour of an alien invasive weed Parthenium hysterophorus was documented according to the extended BBCH scale in four different seasons. A phenological calendar was prepared using both two- and three- digit coding system, precisely describing the developmental stages of the weed. The phenological documentation is further supplemented with the dates corresponding to a particular growth stage, pictures of the representative growth stages and meteorological data of all the four seasons. Results revealed that the phenology of the weed altered in response to the changing temperature and humidity conditions but no apparent climatic condition could inhibit its germination or flowering. However, the emergence of inflorescence was highly sensitive to the temperature/photoperiodic conditions. Variations in the phenological traits of P. hysterophorus with changing environmental conditions explain the acclimatisation potential of the weed permitting its vast spread in the non-native regions. Since the given phenological illustrations are accurate, unambiguous and coded as per an internationally recognised scale, they could be exploited for agronomic practices, weed management programmes, and research purposes.To evaluate the impact of environmental factors (temperature [T] and humidity [RH]) on the invasiveness of Parthenium hysterophorus, we documented the phenological stages of the weed in different seasons using BBCH scale. For this, various growth stages beginning from the dry seeds until the maturity of the plant, were observed and photographed. Phenology of the weed in season 1 and 4 was remarkably different as it involved the formation of rosette stage unlike in season 2 and 3. The outcome of the study is expected to be useful for devising strategies to manage this invasive weed.
      PubDate: 2017-09-12T03:12:00.616313-05:
      DOI: 10.1111/aab.12374
       
  • Slavery in plants: how the facultative hemi-parasitic plant Rhamphicarpa
           fistulosa can completely dominate its host
    • Authors: S. Kabiri; J. Rodenburg, A. van Ast, L. Bastiaans
      Abstract: The rain-fed lowland rice weed Rhamphicarpa fistulosa (Rice Vampireweed) is a facultative root parasitic plant. Growth and reproduction of R. fistulosa benefit considerably from parasitism, but how this affects the host plant is not well established. We determined accumulation and partitioning of rice–parasite biomass in two pot experiments. First, rice (cv. IR64) was grown under eight R. fistulosa densities (15–1000 seeds per pot) with two sampling times. Next, 2 parasite densities (6 and 13 plants per pot) were combined with 9 destructive samplings. Infection increased host root: shoot ratios and decreased host plant height, leaf area and tiller number. Reductions in light interception were followed by reductions in light use efficiency, causing 22–71% losses in host plant biomass and 78–100% losses in host kernel production. Parasitism eventually caused a complete standstill of host plant growth, while the parasite managed to gradually increase its share in total host plant–parasite biomass up to 50–82%. This implies that ultimately the host plant was producing solely for the sake of the parasite. Due to its facultative nature, R. fistulosa may incorrectly be perceived as relatively harmless. Upon infection this Rice Vampireweed, however, turns into a genuine slave master, whereby it completely dominates its host.The rain-fed lowland rice weed Rhamphicarpa fistulosa (Rice Vampireweed) is a facultative root parasitic plant but how this parasite affects the host plant was not well established. Our key findings are that very low infestation levels of R. fistulosa increased host root : shoot ratios, reduced leaf area and tiller numbers and caused stunting. Light interception and light use efficiency were reduced, causing 22–71% losses in rice biomass and 78–100% losses in kernel production. After successful infection, the parasite eventually manipulated rice plants in such a way that they produced assimilates only to benefit the parasite. The good news is that the facultative nature of the parasite ensures that emergence is preceding infection. It takes around 6 weeks before the first symptoms of parasite infection are noticed. Thus, this time lag can be a window of opportunity to control the parasite and prevent severe damage to the crop.
      PubDate: 2017-09-07T02:45:31.045957-05:
      DOI: 10.1111/aab.12378
       
  • Aspects in oat breeding: nutrition quality, nakedness and disease
           resistance, challenges and perspectives
    • Authors: A. Gorash; R. Armonienė, J. Mitchell Fetch, Ž. Liatukas, V. Danytė
      Abstract: Traditionally, the oat crop (Avena sativa) has been neglected in a number of respects, cultivated in cropping areas not optimal for wheat, barley or maize. In recent years the interest in oats has increased, particularly because of its dietary benefits and therapeutic potential for human health. The uniqueness and advantages of naked oats over other popular cereals, due to its potentially valuable nutritional composition, have been well studied and reported, opening new market “niches” for oats. Despite the well-documented benefits, the status of the oat crop is still fragile, due to many reasons. The area cultivated for the oat crop is much less compared with other cereals, and therefore commercial efforts in oat breeding are less. Oat groat yield is lower than other cereals such as wheat and the nutritious uniqueness has not been reflected in agreeable market prices. The same price still exists for both naked and conventional/covered oats in the world grain market. The absence of visible market competitiveness, and some of the oat biological drawbacks, including low grain yield, keeps the oat crop as a lower profitability minor crop. This review is intended to analyse and summarise main achievements and challenges in oat genetics, agronomy and phytopathology to find possible ways of oat improvement and future perspectives for oat breeding.
      PubDate: 2017-09-07T02:35:39.143613-05:
      DOI: 10.1111/aab.12375
       
  • How do weeds differ in their response to the timing of tillage' A
           study of 61 species across the northeastern United States
    • Authors: S. Cordeau; R.G. Smith, E.R. Gallandt, B. Brown, P. Salon, A. DiTommaso, M.R. Ryan
      Abstract: Previous research has demonstrated that the season in which soil is tilled (spring versus fall) can strongly influence weed community assembly and subsequent species composition and abundance in annual cropping systems. Despite this understanding, it is unknown whether finer-scale, within-season variation in the timing of tillage has similar impacts on weed community assembly. We conducted an experiment on four research farms across the northeastern USA to test the effects of tillage timing on weed emergence periodicity. Soil was tilled at 12 different times that were 2 weeks apart from 29 April to 30 September (the entire growing season) and the composition and abundance of the weed seedlings that emerged was measured 6 weeks later. Weed species clustered into three tillage timing groups at the two New York locations and clustered into five tillage timing groups at the New Hampshire and Maine locations. Individual species associated with each window of tillage time varied by location. No single trait or combination of traits were consistently associated with species-by-tillage time groupings across locations; however, within each location several traits were associated with particular groups of species, including: (a) seed length, (b) seed weight, (c) cotyledon type, (d) life span, (e) ploidy level and (f) photosynthetic pathway. These results suggest that fine-scale variation in the timing of tillage can lead to predictable changes in the species composition and trait distribution of weed communities in annually tilled agroecosystems.Weed species differ in their emergence timing, and previous research has shown that agricultural weed communities can vary based on the season in which the soil was tilled. Here we present results from a field experiment that was conducted in order to quantify the emergence timing of different weed species. Violin plots show the kernel density of the emergence of weed species six weeks after soil was tilled. Our results suggest that fine-scale differences in tillage timing can affect weed species composition and trait distribution in weed communities.
      PubDate: 2017-09-06T02:55:48.963299-05:
      DOI: 10.1111/aab.12377
       
  • Novel phytoplasma strains of X-disease group unveil genetic markers that
           distinguish North American and South American geographic lineages within
           subgroups 16SrIII-J and 16SrIII-U
    • Authors: E. Pérez-López; W. Wei, J. Wang, R.E. Davis, M. Luna-Rodríguez, Y. Zhao
      Abstract: Phytoplasmas in the X-disease group (16SrIII) are highly diverse in terms of geographic distributions, vectorship and plant host specificity. Such biological and ecological diversity is often correlated with distinctive genetic markers present in evolutionarily conserved genes. Based on restriction fragment length polymorphism (RFLP) markers in the 16S rRNA gene sequences, 29 subgroups have been delineated, with most of them being found in the Americas. However, it has been unknown whether distinct geographic lineages are present within a given subgroup. Prior to this study, phytoplasmas belonging to subgroups 16SrIII-J and 16SrIII-U were reported only in countries located in South America. In the present study, we identified new phytoplasmas strains closely related to the reference strains of the two subgroups in Mexico, a North American country. These newly identified Mexican strains possess unique RFLP, single nucleotide polymorphism, and fragmental deletion markers in 16S rRNA- and/or ribosomal protein-encoding genes. Since these markers consistently distinguished the Mexican strains from their South American counterparts, they may represent emerging or previously unknown North American geographic lineages of the subgroups 16SrIII-J and 16SrIII-U.Phytoplasmas in the X-disease group (16SrIII) are highly diverse in terms of geographic distributions, vectorship, and plant host specificity. Such biological and ecological diversity is often correlated with distinctive genetic markers present in evolutionarily conserved genes. In the present study, we identified new phytoplasmas strains based on unique RFLP and SNP markers in 16S rRNA and ribosomal protein-encoding genes. These new phytoplasmas were discovered from periwinkle plants growing in Mexico; they may represent North American lineages of the subgroups 16SrIII-J and 16SrIII-U.
      PubDate: 2017-08-17T23:55:47.415983-05:
      DOI: 10.1111/aab.12383
       
  • Relative importance of natural enemies and abiotic factors as sources of
           regulation of mealybugs (Hemiptera: Pseudococcidae) in Brazilian coffee
           plantations
    • Authors: N. Rodrigues-Silva; S. Oliveira Campos, E. Sá Farias, T.C. Souza, J.C. Martins, M.C. Picanço
      Abstract: In the present study, we determined the critical stages and the key factors of mortality for Planococcus citri (Hemiptera: Pseudococcidae) in Brazilian coffee plantations using a life table to understand the role of natural biological control on its population. Predators, parasitoids, rainfall, sunlight, physiological disturbances and fungal diseases were collectively responsible for 98.79% in the total mortality of P. citri. Predators belonging to the Chrysopidae, Syrphidae, Dolichopodidae and Coccinellidae families were the most important mortality factors in the early developmental stages of P. citri (i.e. eggs and 1st and 2nd instar nymphs), whereas predators belonging to the Coccinellidae and Chrysopidae families were the most important mortality factors for the last instars (i.e. 3rd instars and adults) for P. citri. The generalist predators Harmonia axyridis, Chrysoperla genanigra and Chrysoperla externa were the key mortality factors for P. citri. The third nymph stage was considered the critical life stage (i.e. the life stage that most influences population size). Our results show that generalist predators and climatic factors are important sources of natural mortality of P. citri governing the population dynamics of this pest in the field.In this study, we determined the critical stages and the key factors of mortality for Planococcus citri using a life table to understand the role of natural biological control on its population. Predators, parasitoids, rainfall, sunlight, physiological disturbances and fungal diseases were collectively responsible for 98.79% in the total mortality of P. citri. The generalist predators Harmonia axyridis, Chrysoperla genanigra and C. externa were the key mortality factors for P. citri. The third nymph stage was considered the critical mortality stage. Our results show that these generalist predators are important natural control agents of P. citri in the field.
      PubDate: 2017-08-15T01:55:27.770284-05:
      DOI: 10.1111/aab.12373
       
  • Microbe-mediated control of Aspergillus flavus in stored rice grains with
           a focus on aflatoxin inhibition and biodegradation
    • Authors: M. Mannaa; J.Y. Oh, K.D. Kim
      Abstract: Biological control of mycotoxigenic fungi using antagonistic microbes is a promising alternative to agricultural chemicals for postharvest storage. In this study, we evaluated rice-derived bacterial strains to identify biocontrol agents to inhibit Aspergillus flavus in stored rice grains. Consequently, we obtained three potential biocontrol strains (Microbacterium testaceum KU313, Bacillus megaterium KU143 and Pseudomonas protegens AS15) from 26 tested strains that were prescreened from the 460 strains isolated from rice grains. The three selected strains proved to be effective biocontrol agents showing antifungal activity against A. flavus and good colonisation ability on rice grains, along with inhibition of the fungal growth and aflatoxin production. In particular, P. protegens AS15 greatly inhibited the aflatoxins produced by A. flavus on rice grains to 8.68 (percent aflatoxin reduction relative to control = 82.9%) and 18.05 (68.3 %) ng g−1 dry weight of rice grains, compared with the 50.89 and 56.97 ng g−1 dry weight of rice grains of the MgSO4 control at 1 and 2 weeks after inoculation, respectively. In addition, strain AS15 had a significant ability to not only degrade aflatoxin B1 (the most harmful aflatoxin), but also utilise the toxin for bacterial growth in a nutrient-deficient medium. Therefore, the selected bacterial strains could be environmentally sound alternatives for the management of A. flavus and aflatoxin production by reducing the fungal damage to stored rice grains. This would also reduce the human and animal health hazards associated with the consumption of fungus-contaminated rice grains. To our knowledge, this is the first report of the potential of the bacterial species M. testaceum and P. protegens as biocontrol agents for controlling aflatoxigenic A. flavus on stored rice grains.(A) Aflatoxin degradation by bacterial strain AS15, strain KU408 (negative control), and MgSO4 (untreated control) in various diluted nutrient broth supplemented with aflatoxin B1 at 3 days after inoculation; (B) bacterial populations of the treatments in the diluted medium with or without aflatoxin B1.
      PubDate: 2017-08-14T00:30:34.668151-05:
      DOI: 10.1111/aab.12381
       
  • The role of invertebrates in seedling establishment in a heterocarpic
           plant, Atriplex sagittata
    • Authors: A. Honek; Z. Martinkova, S. Koprdova, P. Saska
      Abstract: Seed heteromorphism is a marked character of many Chenopodioideae (Amaranthaceae). Seed morphs differ in dormancy, germination and seedling biology, but differences in their predation have not yet been studied. Atriplex sagittata produces small black dormant and large brown non-dormant seeds. In this study, the timing of seed release and seedling establishment were ascertained, and their consumption by invertebrates (carabids, isopods and slugs) was studied. Seeds dispersed in the autumn passed the winter on the ground surface, protected from invertebrate predation by low temperatures. In the following vegetative season, ungerminated black seeds exposed to predation on ground surface were preferred by a large carabid species, Pseudoophonus rufipes. Some black and all brown seeds escaped predation by germinating in early spring. The seedlings were little endangered by carabids and isopods but were preferred by an invasive slug, Arion vulgaris, the feeding of which can exterminate seedlings at places in which slugs are abundant. Invertebrate predation is important factor of seed and seedling mortality of A. sagittata and seed heteromorphism modifies its intensity and timing.
      PubDate: 2017-07-10T21:35:46.702817-05:
      DOI: 10.1111/aab.12372
       
  • Recent advances and prospects in Prunus virology
    • Authors: M. Rubio; P. Martínez-Gómez, A. Marais, J.A. Sánchez-Navarro, V. Pallás, T. Candresse
      Abstract: The stone fruit genus Prunus, within the family Rosaceae, comprises more than 230 species, some of which have great importance or value as ornamental or fruit crops. Prunus are affected by numerous viruses and viroids linked to the vegetative propagation practices in many of the cultivated species. To date, 44 viruses and three viroids have been described in the 9 main cultivated Prunus species. Seven of these viruses and one viroid have been identified in Prunus hosts within the last 5 years. This work addresses recent advances and prospects in the study of viruses and viroids affecting Prunus species, mostly concerning the detection and characterisation of the agents involved, pathogenesis analysis and the search for new control tools. New sequencing technologies are quickly reshaping the way we can identify and characterise new plant viruses and isolates. Specific efforts aimed at virus identification or data mining of high-throughput sequencing data generated for plant genomics-oriented purposes can efficiently reveal the presence of known or novel viruses. These technologies have also been used to gain a deeper knowledge of the pathogenesis mechanisms at the gene and miRNA expression level that underlie the interactions between Prunus spp. and their main viruses and viroids. New biotechnological control tools include the transfer of resistance by grafting, the use of new sources of resistance and the development of gene silencing strategies using genetic transformation. In addition, the application of next generation sequencing and genome editing techniques will contribute to improving our knowledge of virus–host interactions and the mechanisms of resistance. This should be of great interest in the search to obtain new Prunus cultivars capable of dealing both with known viruses and viroids and with those that are yet to be discovered in the uncertain scenario of climate change.
      PubDate: 2017-06-30T00:55:58.015283-05:
      DOI: 10.1111/aab.12371
       
  • Brazilian melon landraces resistant to Podosphaera xanthii are unique
           germplasm resources
    • Authors: E.W.L.P. Nunes; C. Esteras, A.O. Ricarte, E.M. Martínez, M.L. Gómez-Guillamón, G.H.S. Nunes, M.B. Picó
      Abstract: Podosphaera xanthii is the most important causal agent of powdery mildew in melon, a crop ranked within the most economically important species worldwide. The best strategy to face this fungus disease, which causes important production losses, is the development of genetically resistant cultivars. Genetic breeding programmes require sources of resistance, and a few ones have been reported in melon, mostly in Momordica and Acidulus horticultural groups. However, the existence of many races that reduces the durability of the resistance makes necessary to find new resistant genotypes with different genetic backgrounds.In this work, Brazilian germplasm, together with a set of Indian landraces, and the COMAV's (Institute for the Conservation and Breeding of Agricultural Biodiversity) melon core collection, representing the whole variability of the species, were assessed for resistance against some common races in Spain and Brazil and genotyped with a 123-SNP (single nucleotide polymorphisms) genotyping platform to study the molecular relationships of the resistant accessions. In the first experiment, carried out in Valencia (Spain) in 2013, seventy-nine melon accessions were evaluated using artificial inoculation. Five accessions selected as resistant were also evaluated against races 1, 3, and 5 in Mossoró (Brazil, 2015) and against race 3.5 in Valencia (2016) under greenhouse conditions, and under four field conditions in Brazil. The accessions, AL-1, BA-3, CE-3, and RN-2, within the Brazilian collection, presented resistance against all the races of P. xanthii assayed in all conditions tested. AL-1, CE-3 and RN-2 were molecularly more similar to wild agrestis and Acidulus melons from Asia and Africa, while BA-3 grouped with Momordica types. Molecular analysis also confirmed that these new Brazilian sources of resistance differ from those previously reported, constituting interesting materials to encourage genetic breeding programmes, especially in Brazil and Spain.
      PubDate: 2017-06-30T00:55:24.093169-05:
      DOI: 10.1111/aab.12370
       
  • Detection of Southern tomato virus by molecular hybridisation
    • Authors: A.V. Puchades; C. Carpino, A. Alfaro-Fernandez, M.I. Font-San-Ambrosio, S. Davino, J. Guerri, L. Rubio, L. Galipienso
      Abstract: Southern tomato virus (STV) is a double-stranded RNA (dsRNA) virus belonging to the genus Amalgavirus from the family Amalgamaviridae. STV has been detected in tomato plants showing symptoms of stunting, fruit discoloration and size reduction, although its role on symptom development is unclear. Also, little is known about the incidence and epidemiology of this virus and how it spreads in tomato crops. In this work, we developed a molecular hybridisation method by using a digoxigenin-labelled RNA probe based on the nucleotide sequence of the STV putative coat protein which was tested with different procedures for preparation of plant material. This technique was sensitive enough to detect STV from sap extracts (obtained just by grinding in buffer) from different plant tissues such as leaves, fruits, roots and seeds. This procedure is suitable for field surveys since it allows a cheap and quick processing of a high number of samples. Surveys performed in three important tomato production areas (Peninsular Spain, the Canary Islands and Sicily) showed that STV is widely spread, with incidences ranging from 18% to 74% in different local and commercial tomato varieties.
      PubDate: 2017-06-27T21:35:29.78246-05:0
      DOI: 10.1111/aab.12367
       
  • A chitinase from Euphorbia characias latex is a novel and powerful
           plant-based pesticide against Drosophila suzukii
    • Authors: S. Martos; D. Spanò, N. Agustí, C. Poschenrieder, F. Pintus, L. Moles, R. Medda
      Abstract: Drosophila suzukii attacks on developing soft fruits have recently caused important economic losses in Europe. This study explores the effectiveness of a new control strategy against this insect pest that is based on a plant chitinase extracted from the latex of the Mediterranean spurge, Euphorbia characias. The ability of the purified Euphorbia latex chitinase (ELC) to degrade the chitin exoskeleton of D. suzukii was assessed using confocal laser scanning microscopy. ELC treatment caused reduced larval growth, higher mortality and notable degradation of external insect structures. Therefore, the chitinase may induce a double effect on the D. suzukii larvae, a direct injury on the larval bodies and an action as antifeedant. The effects of the ELC treatment were also tested on leaves of the insect's host plants, Fragaria × ananassa and Rubus idaeus, using physiological parameters (chlorophyll concentration, chlorophyll fluorescence, leaf gas exchange and water potential) and defence gene expression (FaPGIP, FaChi2_1 and FaChi2_2) as stress indicators. ELC at concentrations effective against D. suzukii did not damage the host plants. Only plant defence gene expression was somewhat enhanced during the early hours after ELC application. In conclusion, ELC, a natural product, proved to be an effective tool for use in the development of an environmentally friendly integrated management strategy against D. suzukii, a pest whose control by conventional chemical insecticides is problematic.
      PubDate: 2017-06-26T20:33:01.624411-05:
      DOI: 10.1111/aab.12369
       
  • The role of domestication and maternal effects on seed traits of
           crop–wild sunflower hybrids (Helianthus annuus)
    • Authors: F. Hernández; L.I. Lindström, E. Parodi, M. Poverene, A. Presotto
      Abstract: Hybridisation between crops and their wild relatives may promote the evolution of weeds. Seed germination and dormancy are the earliest life-history traits and are highly influenced by the maternal parent. However, the ecological role of the maternal effect on seed traits in the evolution of crop–wild hybrids has received little attention. In this study, we test the relative importance of maternal and hybridisation effects on seed traits of the first generation of crop–wild sunflower hybrids (Helianthus annuus). Seed germination was tested in two wild populations with contrasting dormancy, two cultivated materials and their reciprocal crosses at four different times after harvest and three different temperatures. Seed germination at each of the four times, after ripening response and secondary dormancy were recorded along with four morphological traits. Additionally, the pericarp anatomy was analysed with light and scanning electron microscopy. We observed strong maternal effects on all seed traits. Seed germination, morphology and pericarp anatomy differed largely between the crop and wild seeds and these traits in the crop–wild hybrids resembled their female parent. Slight but significant hybridisation effects were observed in germination, mainly in seeds produced on wild plants. Crop hybridisation changed seed germination, the after ripening response and secondary dormancy in the crop direction. Morphological and anatomical traits associated with domestication strongly correlated with the observed differences in seed germination and dormancy in crop–wild sunflower hybrids. The large maternal effects along with the evolutionary divergence in seed traits were responsible for the large phenotypic differences observed in crop–wild hybrids with the same genetic composition. Wild-like seed traits of hybrids suggest that there are no barriers to crop gene introgression at the seed level whereas crop-like seed traits could be strongly selected against, conditioning the selection of traits expressed later in the life cycle and in the next generations.
      PubDate: 2017-06-15T00:35:35.230304-05:
      DOI: 10.1111/aab.12368
       
  • Seed treatment with selected plant growth-promoting rhizobacteria
           increases maize yield in the field
    • Authors: G. Breedt; N. Labuschagne, T.A. Coutinho
      Abstract: Maize, Zea mays is the most important grain crop in South Africa and is a staple food in many African countries. The beneficial effects of plant growth-promoting rhizobacteria on crop growth and yield have been well documented, but obtaining reproducible results under field conditions is often difficult. In the current study, five selected rhizobacterial strains that showed plant growth-promoting activities in pilot studies were evaluated for potential enhancement of maize yield under field conditions. The five strains together with a commercial standard were assessed as seed treatments of maize over three seasons in four different soil types. The strains were identified on the basis of 16S rRNA sequencing as Lysinibacillus sphaericus (T19), Paenibacillus alvei (T29), Bacillus safensis (S7) Bacillus pumilus (A26) and Brevundimonas vesicularis (A40). The best yield increases in maize were obtained during the 2011/2012 and 2012/2013 seasons in the Shortlands ecotope with the rhizobacterial strains T19, T29 and S7, resulting in yield increases ranging from 24% to 34%. Strain T19 rendered the most consistent yield increases during the three successive field trials amounting to 33% and 24% in Shortlands ecotope and 12% in Clovalley ecotope, respectively. During 2013/2014 a consortium of three strains, viz. T19, S7 and A26 gave a 32% yield increase in Clovalley ecotope. All the rhizobacterial strains solubilised phosphate in vitro except T19. Strain T29 showed the best nitrogen-fixing activity in vitro, proliferating on a nitrogen-free substrate and also producing ammonia. All the strains tested positive for indole acetic acid production. The current study demonstrates the ability of rhizobacterial strains T19, T29, S7 and A26 applied as seed treatments to significantly enhance maize yield in the field, making development and commercialisation of these strains a viable option.
      PubDate: 2017-06-15T00:35:21.83683-05:0
      DOI: 10.1111/aab.12366
       
  • A discussion on disease severity index values. Part I: warning on inherent
           errors and suggestions to maximise accuracy
    • Authors: K.S. Chiang; H.I. Liu, C.H. Bock
      Abstract: A special type of ordinal scale comprising a number of intervals of known numeric ranges can be used when estimating severity of a plant disease. The interval ranges are most often based on the percent area with symptoms [e.g. the Horsfall–Barratt (H–B) scale]. Studies in plant pathology and plant breeding often use this type of ordinal scale. The disease severity is estimated by a rater as a value on the scale and has been used to determine a disease severity index (DSI) on a percentage basis, where DSI (%) = [sum (class frequency × score of rating class)]/[(total number of plants) × (maximal disease index)] × 100. However, very few studies have investigated the effects of different scales on accuracy of the DSI. Therefore, the objectives of this study were to investigate the process of calculating a DSI on a percentage basis from ordinal scale data, and to use simulation approaches to explore the effect of using different methods for calculation of the interval range and the nature of the ordinal scales used on the DSI estimates (%). We found that the DSI is particularly prone to overestimation when using the above formula if the midpoint values of the rating class are not considered. Moreover, the results of the simulation studies show that, if rater estimates are unbiased, compared with other methods tested in this study, the most accurate method for estimation of a DSI is to use the midpoint of the severity range for each class with an amended 10% ordinal scale (an ordinal scale based on a 10% linear scale emphasising severities ≤50% disease, with additional grades at low severities). As for biased conditions, the accuracy for calculating DSI estimates (%) will depend mainly on the degree and direction of the rater bias relative to the actual mean value.
      PubDate: 2017-06-06T03:20:39.04349-05:0
      DOI: 10.1111/aab.12362
       
  • Persistence of transgenes in wild rice populations depends on the
           interaction between genetic background of recipients and environmental
           conditions
    • Authors: S.S. Dong; M.Q. Xiao, D.X. Ouyang, J. Rong, B.-R. Lu, J. Su, F. Wang, J.K. Chen, Z.-P. Song
      Abstract: The persistence of transgenes in wild populations may cause unintended ecological consequences, and the possibility of transgenes' persistence and introgression is dependent on fitness performance of transgenic crop–wild hybrids. To investigate the effects of transgene and genotype × environment on the fitness of crop–wild rice hybrids, a total of 11 cross-combination progenies between insect-resistant transgene (CpTI and Bt/CpTI) rice lines and wild rice (Oryza rufipogon) were evaluated at different sites with contrasting insect treatments. The results showed that fitness performance varied between transgenic hybrids having different wild parents and under different environmental conditions, indicating that fitness effects of transgenes on hybrid progenies depend heavily on the genetic background of recipient plants and growing environment. Significant fitness advantages conferred by transgenes were found only in some hybrids under high insect pressure condition, demonstrating that the level of target insects in the field environment influences the persistence and spread of insect-resistant transgenes in wild rice populations. These findings suggest that evolutionary fate of escaped transgenes is different in wild populations with diverse genetic backgrounds under various environmental conditions.
      PubDate: 2017-06-01T02:50:28.325977-05:
      DOI: 10.1111/aab.12365
       
  • Probability distributions for marketable pods and white mould on snap bean
    • Authors: D.A. Shah; H.R. Dillard, S.J. Pethybridge
      Abstract: White mould, caused by Sclerotinia sclerotiorum, is one of the most recalcitrant diseases of snap bean. Probability distributions suitable for describing the total number of marketable pods (hereafter simply referred to as pods) per plant, as well as for the number of pods and stems with white mould per plant, have not been identified. The total number of pods and the number of pods and stems with white mould were measured on a per plant basis in plots of processing snap bean (var. Hystyle) in New York. The total number of pods per plant ranged from 0 to 29, and was best described by the Pólya-Aeppli distribution. The number of pods and the number of stems with white mould per plant were well-described by the negative binomial (NB) distribution. A Sarmanov bivariate distribution with NB marginals was derived and fitted to the joint data on the number of pods and stems with white mould per plant, accounting for correlation between pods and stems with white mould on the same plant. The bivariate distribution was used to formulate an empirical equation for the incidence of plants with white mould as a function of the average number of pods and stems with white mould per plant. The results represented a more complete understanding of the distributional properties of white mould in snap bean.
      PubDate: 2017-05-23T04:11:24.960644-05:
      DOI: 10.1111/aab.12363
       
  • Ethylenediamine-N,N′-disuccinic acid mitigates salt-stress damages in
           strawberry by interfering with effects on the plant ionome
    • Authors: R. Aslantas; I. Angin, M. Kose, N. Bernstein
      Abstract: This study evaluated the hypothesis that the organic chelant ethylenediamine-N,N′-disuccinic acid (EDDS) mitigates plant damage under salinity, and that this is accomplished by EDDS-induced effects on cation uptake. Damaging effects of salinity on plants often involve inhibited uptake of nutritional cations, such as K and Ca, and excessive accumulation of Na. Therefore, mechanisms that improve uptake of K and Ca, or reduce Na uptake, have a potential for ameliorating salinity damages. Organic chelants increase heavy-metal cation availability at the site of uptake and increase their uptake by the roots or in planta transport. Although organic chelants are routinely used in agriculture to enhance uptake of heavy-metal cations into plants, and for soil bioremediation, their effect on uptake of cation-macronutrients is not known, and neither is their impact on plant function under salinity. In this study, we evaluated the response of strawberry plants to EDDS application (0, 1, 3 and 5 mmol kg soil−1), under six levels of NaCl (0, 3, 6, 9, 12 and 15 mmol L−1). EDDS application under salinity improved vegetative development, as well as reproductive growth and chlorophyll content, with statistically significant interaction between chelant dosage and level of salinity. The mitigation of salinity damage by EDDS occurred at high salinity treatments (from 9 mM NaCl). Application rates of 1–3 mmol EDDS kg−1 were optimal for mitigating salinity effects on reproductive development, but in accordance with the extent of chelant-induced accumulation of the macronutrients K, Ca and P in the leaves, higher application rates (3–5 mmol EDDS kg−1) were required for optimal improvement of vegetative development. These results suggest that EDDS improves plant function under mild salinities by interfering with salinity effects on the plant ionome.
      PubDate: 2017-05-23T03:40:29.654703-05:
      DOI: 10.1111/aab.12364
       
  • Effects of Grapevine leafroll-associated virus 3 on the physiology in
           asymptomatic plants of Vitis vinifera
    • Authors: R. Montero; H. El aou ouad, D. Pacifico, C. Marzachì, N. Castillo, E. García, N.F. Del Saz, I. Florez-Sarasa, J. Flexas, J. Bota
      Abstract: Grapevine leafroll disease is one of the most important viral diseases of grapevine (Vitis vinifera) worldwide. Grapevine leafroll-associated virus 3 (GLRaV-3) is the most predominant virus species causing this disease. Therefore, it is important to identify GLRaV-3 effects, especially in plants which do not systematically show visual symptoms. In this study, effects of GLRaV-3 on grapevine physiology were evaluated in asymptomatic plants of Malvasía de Banyalbufar and Cabernet Sauvignon cvs. Absolute virus quantification was performed in order to determine the level of infection of the treatment. The net carbon dioxide (CO2) assimilation (AN) and electron transport rate (Jflux) were the main parameters affected by the virus. The AN reduction in infected plants was attributed to restrictions in CO2 diffusion caused by anatomical leaf changes and a reduction of Rubisco activity. Those effects were more evident in Malvasia de Banyalbufar plants. The reduction of AN leads to a decrease in the total oxygen uptake rate by the activity of the cytochrome oxidase pathway, producing slight differences in plant growth. Therefore, even though no symptoms were expressed in the plants, the effects of the virus compromised the plant vital processes, showing the importance of early detection of the virus in order to fight against the infection.
      PubDate: 2017-05-17T03:41:11.103456-05:
      DOI: 10.1111/aab.12356
       
 
 
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