Download or read book Increasing Weed management Tools with an Herbicide Safener for Control of Annual Grasses in Wheat written by Damilola A. Raiyemo and published by . This book was released on 2020 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Pacific Northwest is a highly productive wheat growing region of the world. One of the challenges confronting wheat farmers in the region is control of weeds below levels that negatively impact crop yield. Annual grasses are most troublesome to wheat farmers in the region due to similarities in growth habits between wheat and annual grasses. Growers often rely on preemergence or early postemergence herbicides for control of annual grasses. Preemergence herbicides include the very-long-chain fatty acid synthesis (VLCFA) inhibitors, such as flufenacet, pyroxasulfone or their premix with other herbicides while early postemergence herbicides include (1) acetyl CoA carboxylase (ACCase) inhibitors, such as diclofop, pinoxaden, and (2) acetolactate synthase (ALS) inhibitors, such as flucarbazone, pyroxsulam, mesosulfuron. However, selection pressure from consistent herbicide use resulted in annual grasses evolving resistant populations to multiple groups of herbicides, leaving growers with few herbicide options for control. The very-long-chain fatty acid-inhibiting herbicides are effective herbicides for control of annual grasses and small-seeded broadleaf weeds in corn, soybeans, wheat, cotton and sorghum with few reported cases of resistance. Pyroxasulfone, a VLCFA inhibitor, controls annual grass and small-seeded broadleaf weeds such as Italian ryegrass, barnyardgrass, foxtails, crabgrasses, Palmer amaranth and common waterhemp in corn, wheat and soybeans at low use rate with efficacy also against populations resistant to glyphosate, acetolactate synthase inhibitors, acetyl CoA carboxylase inhibitors and triazines. Despite the use of several VLCFA inhibitors for over six decades, potential problem associated with herbicides in the group is crop injury. Differential tolerance of crop varieties under adverse environmental conditions or soil type could hinder the selective use of some herbicides. Herbicide safeners, applied either as tank mixture with the herbicide for preemergence or postemergence use or as seed treatments in the form of seed dressing have been used to protect crops from herbicide injury. Safeners increase the expression of genes encoding enzymes involved in herbicide detoxification including cytochrome P450 monooxygenases, glycosyltransferases, glutathione S-transferases and ATP-binding cassette transporters. Fluxofenim (Concep III, Syngenta Crop Protection, LLC, Greensboro, NC) is a widely used seed treatment safener for protection of sorghum from S-metolachlor injury at the rate of 0.4 g ai kg-1 seed. Perhaps, fluxofenim could protect newly bred wheat cultivars of the Pacific Northwest from soil-applied preemergence herbicides. Chapter 1 includes a general introduction to wheat production in Idaho, challenges of annual grass control in wheat, herbicide options for annual grass control in wheat, effectiveness of very-long-chain fatty acid-inhibiting herbicides in annual grass control, tolerance of crops to VLCFA inhibitors via rapid metabolism, concept of crop safening, history, mechanism of action and use. Chapter 2 provides information on series of experiments evaluating the protection of soft white wheat varieties and a hard spring wheat variety from very-long-chain fatty acid-inhibiting herbicides using fluxofenim safener. Data analysis showed that fluxofenim protection of soft white wheat varieties from VLCFA-inhibiting herbicides was variety-dependent. Fluxofenim significantly increased dry biomass of varieties LWW 15-72223, LWW 14-75044, Bruneau and UI Sparrow for S-metolachlor and dimethenamid-P herbicides, and LWW 15-72458 for pyroxasulfone herbicide. Varieties 09-15702A, UI Castle CL+ and UI Palouse CL+ were however tolerant to the three herbicide treatments regardless of fluxofenim treatment at the herbicide rates evaluated. Dose-response analysis showed effective doses resulting in 10% biomass reduction due to fluxofenim-alone treatment ranged from 0.55 g ai kg-1 seed for UI Magic CL+ to 1.23 g ai kg-1 seed for UI Palouse CL+. Effective doses resulting in 90% tolerance to S-metolachlor due to fluxofenim ranged from 0.07 g ai kg-1 seed for UI Castle CL+ to 0.55 g ai kg-1 seed for Brundage 96 and a similar pattern of response to dimethenamid-P and pyroxasulfone herbicides were also observed for the varieties, suggesting UI Castle CL+ has some level of tolerance to the herbicides. Glutathione S-transferase (GST) assay revealed that variety UI Castle CL+ had a 58% increase in GST specific activity relative to UI Sparrow and Brundage 96 with 30% and 38% increase in enzyme activity respectively at 0.36 g ai kg-1 seed treatment. Chapter 3 describes experiments to determine fluxofenim protection of six soft white winter wheat varieties selected based on prior greenhouse experiments from S-metolachlor, dimethenamid-P or pyroxasulfone injury under field conditions. Wheat density, height, head count and grain yield were evaluated in response to herbicide treatments with or without fluxofenim safener. Results indicated that fluxofenim had a negative impact on parameters observed in these field studies. Fluxofenim at 0.4 g ai kg-1 seed sorghum label rate failed to confer protection to soft white wheat varieties in the field studies conducted in fall 2018. The results of these field studies were therefore inconclusive and efficacy of fluxofenim to protect winter wheat would need to be evaluated further under different environmental conditions and soil types.
Download or read book Systems of Weed Control in Wheat in North America written by William W. Donald and published by . This book was released on 1990 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Herbicides for Annual Weed Control in Eastern Oregon Wheat written by Donald J. Rydrych and published by . This book was released on 1984 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Herbicides for Annual Weed Control in Wheat in Eastern Oregon written by Donald J. Rydrych and published by . This book was released on 1981 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book National Summit on Strategies to Manage Herbicide Resistant Weeds written by National Research Council and published by National Academies Press. This book was released on 2012-10-22 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: Preserving the efficacy of herbicides and of herbicide-resistance technology depends on awareness of the increasing resistance of weeds to herbicides used in agriculture and coordinated action to address the problem by individuals at the farm level and beyond. This summit served as a venue to bring the attention of important stakeholders to the issue and as an opportunity for experts from diverse disciplines to strategize in a coordinated way to address herbicide-resistant weeds. In convening stakeholders for this event, participants took a step toward a recommendation from the 2010 National Research Council report The Impact of Genetically Engineered Crops on Farm Sustainability in the United States that federal and state government agencies, private-sector technology developers, universities, farmer organizations, and other relevant stakeholders collaborate to document emerging weed-resistance problems and to develop cost-effective resistance-management programs and practices that preserve effective weed control. The summit provided the opportunity for stakeholders to explore the scientific basis of the emergence of herbicide resistance and to consider different perspectives on both opportunities and barriers to overcoming the problem of herbicide-resistant weeds. National Summit on Strategies to Manage Herbicide-Resistant Weeds contains a brief synopsis of key points made by each speaker at the summit.
Download or read book Crop Management Systems to Improve the Competitiveness of Wheat Against Weeds and Reduce the Reliance on Herbicides written by Cory Fee and published by . This book was released on 1997 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Harvest Weed Seed Control written by Drew J. Lyon and published by . This book was released on 2019 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Herbicide resistance is of growing concern to wheat growers in the Pacific Northwest (PNW). Harvest weed seed control (HWSC) is an innovative, non-chemical approach developed in Australia that takes advantage of seed retention at maturity in many dominant annual weed species. Harvest weed seed control systems are focused on the management of chaff material in which most weed seed resides. Although HWSC has not been fully evaluated in the PNW, early work suggests that it can be an effective tool in an integrated weed management program. The choice of which particular HWSC system to use is dependent on the constraints of the cropping systems in which they are used and the specific needs of the grower. This publication discusses the various HWSC systems and their potential suitability for PNW wheat production systems across rainfall regions.
Download or read book Integrated Weed Management in Kansas Winter Wheat written by Dawn E. Refsell and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Integrated weed management (IWM) is an ecological approach to weed control that reduces dependence on herbicides through understanding of weed biology and involves using multiple weed control measures including cultural, chemical, mechanical and biological methods. The critical period of weed control is the duration of the crop life cycle in which it must be kept weed-free to prevent yield loss from weed interference. Eight experiments were conducted throughout Kansas between October 2010 and June 2012 to identify this period in winter wheat grown under dryland and irrigated conditions. Impact of henbit and downy brome density on winter wheat yields were evaluated on four farmer's fields with natural populations and on a research station with overseeded populations. Henbit density up to 156 plants m−2 did not affect winter wheat yield, while downy brome at a density of 40 plants m−2 reduced yield by 33 and 13% in 2011 and 2012, respectively. In the presence of downy brome, winter wheat should be kept weed-free approximately 30 to 45 days after planting to prevent yield loss; otherwise, weeds need to be removed immediately following release from winter dormancy to prevent yield loss due to existing weed populations. Flumioxazin and pyroxasulfone are herbicides registered for use in winter wheat, soybean and corn for control of broadleaf and grass weeds. Flumioxazin and pyroxasulfone were evaluated for plant response to localized herbicide exposure to roots, shoots, or both roots and shoots utilizing a novel technique. Two weed species, ivyleaf morningglory and shattercane, as well as two crops, wheat and soybean, were evaluated for injury after localized exposures. The location and expression of symptoms from the flumioxazin and pyroxasulfone herbicides were determined to be the shoot of seedling plants. The utilization of preemergence herbicides in winter wheat is not a common practice, although application may protect winter wheat from early season yield losses as determined by the critical weed-free period. Kansas wheat growers should evaluate the presence and density of weed species to determine which weed management strategy is most advantageous to preserving winter wheat yield.
Download or read book Herbicides written by Andrew Price and published by BoD – Books on Demand. This book was released on 2013-06-12 with total page 666 pages. Available in PDF, EPUB and Kindle. Book excerpt: Herbicide use is a common component of many weed management strategies in both agricultural and non-crop settings. However, herbicide use practices and recommendations are continuously updated and revised to provide control of ever-changing weed compositions and to preserve efficacy of current weed control options. Herbicides - Current Research and Case Studies in Use provides information about current trends in herbicide use and weed control in different land and aquatic settings as well as case studies in particular weed control situations.
Download or read book Weed Management Strategies for Wheat in the Irrigated Punjab written by and published by . This book was released on 1988 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Weed Control Using Herbicides and Planting Pattern in Wheat written by Tesfay Amare and published by . This book was released on 2014-08-09 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Weed Control Manual written by and published by . This book was released on 1976 with total page 944 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Weed and Crop Resistance to Herbicides written by Rafael de Prado and published by Springer Science & Business Media. This book was released on 1997-05-31 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent decades, repeated use of herbicides in the same field has imposed selection for resistance in species that were formerly susceptible. On the other hand, considerable research in the private and public sectors has been directed towards introducing herbicide tolerance into susceptible crop species. The evolution of herbicide resistance, understanding its mechanisms, characterisation of resistant weed biotypes, development of herbicide-tolerant crops and management of resistant weeds are described throughout the 36 chapters of this book. It has been written by leading researchers based on the contributions made at the International Symposium on Weed and Crop Resistance to Herbicides held at Córdoba, Spain. This book will be a good reference source for research scientists and advanced students.
Download or read book 1972 Herbicides for Annual Weed Control in Wheat in Eastern Oregon written by Donald J. Rydrych and published by . This book was released on 1972 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Competitive Effects and Control of Weeds in Winter Wheat on the Anatolian Plateau Turkey written by Cengiz Tezel and published by . This book was released on 1975 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wheat is the major crop produced on the Anatolian Plateau of Turkey. Annual weeds cause large yields reductions in the wheat crop. Several formulations of 2, 4-D and mixtures of 2, 4-D and 2,4, 5-T are the only materials currently available for use in Turkey on wheat. The objective of this study was to determine the optimum time for application of herbicides in order to reduce competition between winter wheat (Triticum aestivum cv. 'Bolal') and annual weeds. Several herbicides and herbicide mixtures were compared for their effectiveness against two major weed species, yellowweed (Boreava orientalis L.) and cornflower (Centaurea cyanus L.). Herbicides were applied at three different dates according to growth stages of wheat and weeds. Two series of handweeded plots were also included. One set allowed weed competition with the wheat for 4 and 8 weeks and was handweeded for the remainder of the season. The other set was kept free of weeds for 4 and 8 weeks and left weedy for the remainder of the season. Weed-free and weedy control plots were included. Wheat which was free from weed competition in the early part of the growing season produced the highest yields. Plots on which herbicides were applied at the earliest date produced higher yields than where herbicides were applied later. Optimum time for herbicide application was when wheat was in the two to three tiller stage and weeds were small, five to six leaf stage. Delaying the application of herbicides beyond the critical period of competition, which is determined by stage of growth of weeds and wheat, resulted in a continuing decrease in wheat yields. Chemicals which produced satisfactory weed control and increased wheat yields were, 2,4-D, 2,4-D + 2,4,5-T, bromoxynil + MCPA, and terbutryn + 2,4-D combinations. The terbutryn + 2,4-D combination needs further research because of possible phytotoxicity to wheat. It was concluded that using only herbicides now available in Turkey, wheat yield increases of 25 to 50% or more are possible by applying herbicides at the optimum time.
Download or read book Herbicides for Annual Weed Control in Eastern Oregon Wheat written by D.J. Rydrych and published by . This book was released on 1984 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Weed Control Manual and Herbicide Guide written by and published by . This book was released on 1972 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:
