Download or read book Quantifying Yield Losses Due to Barley Yellow Dwarf on Winter Wheat in Kansas Using Disease Phenotypic Data written by Genna Marie Gaunce and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Barley yellow dwarf (BYD) is one of the most important wheat diseases in the state of Kansas. Despite the development of cultivars with improved levels of resistance to BYD, little is known about the impact that this resistance has on yield loss from the disease. The intent of this research was to estimate yield loss in winter wheat cultivars in Kansas due to BYD and quantify the reduction in losses associated with resistant cultivars. During seven years, BYD disease incidence was visually assessed on numerous winter wheat cultivars in replicated field nurseries. Cultivars were planted about three weeks early to promote disease. When grain yields were regressed against BYD incidence scores, negative linear relationships significantly fit the data for each year and for the combined dataset covering all seven years. The models showed that, depending upon the year, 19-48% (average 33%) of the yields was explained by BYD incidence. For the combined dataset, 29% of the relative yield was explained by BYD incidence. The models predicted that cultivars showing high disease incidence had 25-86% (average 49%) less yield than a hypothetical cultivar that showed zero incidence. Using the models, the moderate level of resistance in the cultivar Everest was calculated to reduce yield loss from BYD by about 73%. Therefore, utilizing visual BYD symptom evaluations in Kansas, coupled with grain yields, is useful to estimate yield loss from the disease. Furthermore, linear models that incorporate those parameters can be used to calculate the impact of improving cultivar resistance to BYD on yield losses.
Download or read book Barley Yellow Dwarf Disease written by Monique Henry and published by CIMMYT. This book was released on 2002* with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Wheat Yield and Barley Yellow Dwarf Virus Infection as Affected by Planting Date Ahd Chemical Control written by Salani Nkhori and published by . This book was released on 1997 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Cyber age Approach for Global Management of Barley Yellow Dwarf Virus in Winter Wheat written by Joseph Walls and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Precision agriculture often uses computer-based decision-support systems (DSS's) to disseminate pest and disease information to growers to more efficiently manage agricultural productions. In this thesis, a DSS is developed to be accessed by growers for management of barley yellow dwarf disease caused by Barley yellow dwarf virus. The disease devastates grain growing regions around the world in epidemic patterns. It is a well-studied disease, but management can be greatly improved with determination of necessity and optimal timing of insecticide-treated seed, planting date, pest scouting, and foliar insecticide spray treatments, in chronological order. Using published literature and interviews with experts in BYDV epidemiology and agricultural decision-making, dependency networks were used to model field conditions that would logically warrant these management actions. The networks represented nine possible outputs: use insecticide-treated seed, use untreated seed, plant crop immediately, delay planting, scout for aphid vectors of BYDV, do not scout, full foliar insecticide spray, 1/2 (diluted) insecticide spray, and no insecticide spray. There were a total of 243 total combinations of conditions to reach the seed treatment recommendations, 9,720 to reach the planting date recommendations, 62,208 to reach the scouting recommendations, and 216 to reach the insecticide spray recommendations. In this work, I consider and strive to improve the mechanism for inferring output recommendations even when using only partial data sets.Inference mechanisms are necessary components of DSS's to extrapolate outputs from input data to give users recommendations. The dependency networks represent inference mechanisms that require all input information be present before a management recommendation can be made. This thesis proposes a novel secondary inference mechanism structure to be overlaid onto the dependency networks that uses a numerical, rather than categorical or ordinal, calculation system to handle partial input information. This inference mechanism used the dependency networks as a template to make a prototype numerical representation of importance of field conditions in making management decisions. Secondly it calculates a likely success of these management decisions when executed, and penalizes the grower if he or she executes an incorrect management tactic. The success or penalties are measured in terms of optimum yield. It is also proposed that this secondary inference mechanism can allow a BYD management decision forecast based on pest and disease statuses, as well as real-time recommendations. The purpose of the DSS developed in this thesis is to show the applicability of implementing DSS's based on expert knowledge into a platform (iPIPE) that is capable of gathering data from users in a two-way feedback loop. Since future management decisions rely on previous ones the feedback loop allows management practices conducted by the grower to alter future management recommendations given by the system. It also enhances large scale (regional) pest monitoring with input of individual field data. The DSS reported in this thesis will serve as a basis for the evolution of precision management of crop diseases. It will aid in reducing input cost and increasing sustainability and cereal grain yield in BYD management and eventually it will serve as model to better manage other crop pests and diseases.
Download or read book Plant Diseases Barley Yellow Dwarf Virus in Winter Wheat written by Washington State University. Cooperative Extension Service and published by . This book was released on 1983 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bibliography of Agriculture written by and published by . This book was released on 1996 with total page 2376 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Eriophyoid Mites written by E.E. Lindquist and published by Elsevier. This book was released on 1996-07-03 with total page 823 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a timely compilation of synthesized information on behaviourally fascinating and economically important mites. The book gives much attention to fundamental aspects of eriophyoid anatomy, behaviour, ecology and even systematics, as bases for understanding the ways of life of eriophyoid mites and their effects on host plants; in turn, this will lead to developing the most appropriate means of regulating mites as detrimental or beneficial organisms. It presents new views intended to stimulate interest in eriophyoids and their enemies, and it points to areas where further research is needed. This book is intended for extension workers, experts of acarology and plant protection as well as students, teachers and researchers. It stimulates readers to critically test the view presented and aimes ultimately toward environmentally safe, sustainable and economically efficient means of regulating detrimental and beneficial eriophyoid mites.
Download or read book The Cereal Rusts Origins specificity structure and physiology written by William Rodgers Bushnell and published by . This book was released on 1984 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: Origins, specificity, structure, and physiology; Evolution at the center of origin; Taxonomy of the cereal rust fungi; Specificity; The formae speciales; Race specificity and methods of study; Genetics of the pathogen: host association; Histology and molecular biology of host: parasite; Virulence frequency dynamics of cereal rust fungi; The rust fungus; Controlled infection by Puccinia graminis f.sp. tritici under artificial conditions; Developmental ultrastructure of hyphae and spores; Development and physical of teliospores; Obligate parasitism and axenic culture; The host parsite interface; The rusted host; Effects of rust on plant development in relation to the translocation of inorganic and organic solutes.
Download or read book Agrindex written by and published by . This book was released on 1991 with total page 1546 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Yield gap analysis of field crops written by Food and Agriculture Organization of the United Nations and published by Food & Agriculture Org.. This book was released on 2018-06-29 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: To feed a world population that will exceed 9 billion by 2050 requires an estimated 60% increase over current primary agricultural productivity. Closing the common and often large gap between actual and attainable crop yield is critical to achieve this goal. To close yield gaps in both small and large scale cropping systems worldwide we need (1) definitions and techniques to measure and model yield at different levels (actual, attainable, potential) and different scales in space (field, farm, region, global) and time (short and long term); (2) identification of the causes of gaps between yield levels; (3) management options to reduce the gaps where feasible and (4) policies to favour adoption of sustainable gap-closing solutions. The aim of this publication is to critically review the methods for yield gap analysis, hence addressing primarily the first of these four requirements, reporting a wide-ranging and well-referenced analysis of literature on current methods to assess productivity of crops and cropping systems.
Download or read book Managing Global Genetic Resources written by National Research Council and published by National Academies Press. This book was released on 1993-02-01 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt: This anchor volume to the series Managing Global Genetic Resources examines the structure that underlies efforts to preserve genetic material, including the worldwide network of genetic collections; the role of biotechnology; and a host of issues that surround management and use. Among the topics explored are in situ versus ex situ conservation, management of very large collections of genetic material, problems of quarantine, the controversy over ownership or copyright of genetic material, and more.
Download or read book Aphids as Crop Pests 2nd Edition written by Helmut F van Emden and published by CABI. This book was released on 2017-08-23 with total page 716 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aphids are among the major global pest groups, causing serious economic damage to many food and commodity crops in most parts of the world. This revision and update of the well-received first edition published ten years ago reflects the expansion of research in genomics, endosymbionts and semiochemicals, as well as the shift from control of aphids with insecticides to a more integrated approach imposed by increasing resistance in the aphids and government restrictions on pesticides. The book remains a comprehensive and up-to-date reference work on the biology of aphids, the various methods of controlling them and the progress of integrated pest management as illustrated by ten case histories.
Download or read book Neglected Crops written by J. Esteban Hernández Bermejo and published by Food & Agriculture Org.. This book was released on 1994 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: About neglected crops of the American continent. Published in collaboration with the Botanical Garden of Cord�ba (Spain) as part of the Etnobot�nica92 Programme (Andalusia, 1992)
Download or read book Insect Pests of Rice written by M. D. Pathak and published by Int. Rice Res. Inst.. This book was released on 1994 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Plant Nutrition written by Allen V. Barker and published by CRC Press. This book was released on 2016-04-19 with total page 662 pages. Available in PDF, EPUB and Kindle. Book excerpt: The burgeoning demand on the world food supply, coupled with concern over the use of chemical fertilizers, has led to an accelerated interest in the practice of precision agriculture. This practice involves the careful control and monitoring of plant nutrition to maximize the rate of growth and yield of crops, as well as their nutritional value.
Download or read book Areawide Pest Management written by Opender Koul and published by CABI. This book was released on 2008 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pest management has long been a problem for farmers worldwide and new techniques are continually being developed to reduce the adverse effects of pest populations. The use of areawide pest management has increased dramatically over the past decade and offers potential advantages to traditional and more localized approaches. Suppression over a broad area can reduce re-infestation of previously treated areas and the specific pest management techniques may be more effective when applied over larger areas. Providing the first comprehensive discussion of areawide pest management, this book will explore the theoretical development and implementation of techniques from a worldwide perspective. Areas covered include history and development, biological and ecological impacts and recent case studies of pest management programmes.
Download or read book Mosaic Diseases of Wheat and Related Cereals written by Harold Hall McKinney and published by . This book was released on 1937 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
