Download or read book Palmer Amaranth Control in Established Alfalfa and Documentation of Glyphosate resistant Amaranthus Species in Kansas written by Joshua Adam Putman and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Palmer amaranth is a troublesome weed that competes for water, nutrients, and sunlight in many cropping systems throughout the United States. It is a serious production problem for alfalfa growers in the southern Great Plains region because of extended germination and impact on forage quality and yields. Glyphosate has been used extensively to control Palmer amaranth but control has become difficult. The objectives of this research were to (1) evaluate various herbicide treatments for Palmer amaranth control in established alfalfa, (2) confirm the presence and scope of glyphosate-resistance in common waterhemp and Palmer amaranth populations in eastern Kansas, and (3) to characterize glyphosate-resistance in two Palmer amaranth populations from south central Kansas. Residual Palmer amaranth control in alfalfa varied among herbicide treatments. The best late season Palmer amaranth control was accomplished with sequential treatments that included flumioxazin at 140 g ha−1 or diuron at 2,690 g ha−1 as dormant applications followed by a between cutting treatment of flumioxazin at 70 g ha−1, which was still providing 85 to 96% control in late summer. Several other treatments provided good early season Palmer amaranth control, but control diminished as the season progressed. Palmer amaranth emerges throughout the growing season and therefore, sequential herbicide treatments with good residual activity may be necessary for season-long control. Greenhouse studies indicated that glyphosate-resistant common waterhemp is present throughout eastern Kansas with several populations that survived glyphosate up to two times the suggested use rate. Glyphosate-resistant Palmer amaranth was documented in several populations collected from various counties throughout Kansas. Two populations collected in south central Kansas in 2011 survived up to eight times the typical field use rate of glyphosate. Six more populations collected in 2012 displayed similar resistance characteristics with three populations surviving up to four times the typical rate of glyphosate. Shikimate assays on susceptible and resistant Palmer amaranth biotypes confirmed resistance to glyphosate.
Download or read book Physiological and Genetic Characterization of 2 4 D resistant Palmer Amaranth Amaranthus Palmeri S Watson and Its Management written by Chandrima Shyam and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Palmer amaranth (Amaranthus palmeri S. Watson) is one of the topmost troublesome, C4 dioecious weeds in the US. Biological traits such as aggressive growth habits, prolific seed production, and the ability to withstand environmental stresses hinder control of this weed. Additionally, numerous Palmer amaranth populations across the US have been found to have evolved resistance to multiple herbicides. In 2018, a population of Palmer amaranth from a conservation tillage study from Riley County, Kansas was suspected to have evolved resistance to multiple herbicides including 2,4-dichlorophenoxyacetic acid (2,4-D) and was designated as Kansas Conservation Tillage Resistant (KCTR). 2,4-D, a synthetic auxin herbicide, is widely used for controlling broadleaf weeds in cereal crops. However, over-reliance on 2,4-D to control other herbicide-resistant weeds, along with the commercialization of 2,4-D-tolerant crop technology, has resulted in increased usage of this herbicide. The objectives of this dissertation were to 1) characterize the evolution of multiple herbicide resistance including 2,4-D in KCTR Palmer amaranth; 2) investigate the physiological mechanism of 2,4-D resistance in KCTR compared to two known susceptible Palmer amaranth populations i.e., Kansas Susceptible (KSS) and Mississippi Susceptible (MSS); 3) assess the genetic basis of 2,4-D resistance in KCTR; and 4) evaluate herbicide programs that can manage glyphosate-resistant Palmer amaranth in 2,4-D tolerant soybean. Experiments were conducted under either greenhouse or controlled growth chamber conditions. Standard herbicide dose-response, physiological, biochemical (using radiolabeled herbicides), breeding, and field experiments were designed and conducted. The results of these experiments found that KCTR Palmer amaranth had evolved resistance to six herbicide modes of action, including acetolactate synthase (ALS)-, photosystem II (PS II)-, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS)-, 4-hydroxyphenylpyruvate dioxygenase (HPPD)-, protoporphyrinogen oxidase (PPO)- inhibitors, and synthetic auxins (2,4-D). Sequencing and analyses of genes coding for the herbicide targets indicated absence of all known mutations that confer resistance, except for EPSPS-inhibitor, with a massive amplification of EPSPS gene (up to 88 copies). Investigation of non-target site resistance mechanism(s) in KCTR confirmed the predominance of metabolic resistance to multiple herbicides mediated by either cytochrome P450 (P450) or glutathione S-transferase enzyme activity. Whole-plant dose-response analyses confirmed a 6- to 11- fold resistance to 2,4-D in KCTR compared to two susceptible populations (KSS or MSS). [14C] 2,4-D uptake and translocation studies indicated a 10% less and 3 times slower translocation of [14C] 2,4-D in KCTR compared to susceptible populations, while there was no difference in the amount of [14C] 2,4-D absorbed. However, KCTR plants metabolized [14C] 2,4-D much faster than the susceptible KSS and MSS, suggesting that enhanced metabolism bestows resistance to this herbicide in KCTR. Further, use of P450-inhibitor (e.g., malathion) indicated that the metabolism of 2,4-D in KCTR is mediated by P450 activity. Genetic analyses of F1 and F2 progenies, derived from crossing between KCTR and KSS, revealed that 2,4-D resistance in KCTR Palmer amaranth is an incompletely dominant, nuclear trait. Segregation of F2 progenies did not follow the Mendelian single gene inheritance model (3:1), suggesting the involvement of multiple genes in mediating 2,4-D resistance in KCTR. Evaluation of herbicide programs for Palmer amaranth management in the field suggested that pre-emergence herbicides with residual activity followed by post-emergence application of either 2,4-D or glufosinate or 2,4-D and glufosinate can control glyphosate-resistant Palmer amaranth in 2,4-D-tolerant soybean. Overall, the outcome of this dissertation documents the first case of a six-way resistance in a single Palmer amaranth population and also for the first time characterizes the physiological and genetic basis of 2,4-D resistance in this weed. These findings will help in predicting and minimizing further evolution and spread of 2,4-D resistance in Palmer amaranth.
Download or read book Palmer Amaranth Amaranthus Palmeri Control in Double crop Dicamba glyphosate Resistant Soybean Glycine Max and Dicamba and 2 4 D Efficacy on Palmer Amaranth and Common Waterhemp Amaranthus Rudis written by Nathaniel Russell Thompson and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Auxin herbicides have been widely used for broadleaf weed control since the mid-1940's. With new auxinic herbicide-resistant traits in corn, soybean, and cotton, use of these herbicides is likely to increase. Glyphosate-resistant Palmer amaranth (Amaranthus palmeri) and common waterhemp (Amaranthus rudis) are two primary problematic weed species that will be targeted with dicamba and 2,4-D in the new systems. No-till double-crop soybean after winter wheat harvest is a popular cropping system in central and eastern Kansas, however, management of glyphosate resistant Palmer amaranth has become a serious issue. Field experiments were established near Manhattan and Hutchinson, KS, in 2016 and 2017, to compare seventeen herbicide treatments for control of Palmer amaranth and large crabgrass (Digitaria sanguinalis) in dicamba/glyphosate resistant no-till double-crop soybean after winter wheat. Herbicide programs that included a residual preemergence (PRE) treatment followed by a postemergence (POST) treatment offered greater Palmer amaranth control 8 weeks after planting when compared to PRE-only, POST-only and burndown-only treatments. All treatments that contained glyphosate POST provided complete control of large crabgrass compared to less than 43% control with PRE-only treatments. Soybean grain yield was greater in programs that included PRE followed by POST treatments, compared to PRE-only and burndown-only treatments. A second set of field experiments were established in 2017 near Manhattan and Ottawa, KS to evaluate dicamba and 2,4-D POST efficacy on Palmer amaranth and common waterhemp. Five rates of dicamba (140, 280, 560, 1121, and 2242 g ae ha−1) and 2,4-D (140, 280, 560, 1121, and 2242 g ae ha−1) were used to evaluate control of the Amaranthus spp. Each experiment was conducted twice at each location. Dicamba provided better Palmer amaranth and common waterhemp control than 2,4-D across the rates evaluated. Control of Palmer amaranth was 94% and 99% with dicamba rates of 1121 and 2242 g ae ha−1, respectively, but 2,4-D never provided more than 80% control at any rate. The highest rates of both dicamba and 2,4-D provided greater than 91% common waterhemp control, but control was less than 78% with all other rates of both herbicides. Palmer amaranth and common waterhemp control did not exceed 73% with the highest labelled POST rates of either dicamba or 2,4-D. Auxinic herbicide-resistant traits in corn, soybean, and cotton offer new options for controlling glyphosate-resistant Palmer amaranth and common waterhemp, however proper stewardship is vital to maintain their effectiveness.
Download or read book Integration and Management of Winter annual Cover Crops and Herbicides to Control Glyphosate resistant Palmer Amaranth Amaranthus Palmeri S Wats written by Matthew Scott Wiggins and published by . This book was released on 2014 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main objective of this research was to evaluate the integration of high residue winter-annual cover crops with herbicides, both preemergence and postemergence, to control glyphosate-resistant Palmer amaranth. The results of these trials indicated that winter-annual cover crops improved early-season weed suppression. However, cover crops alone or as part of an integrated weed management system including only preemergence or only postemergence herbicides was not sufficient to control of glyphosate-resistant Palmer amaranth. Therefore, winter-annual cover crops should be used in conjunction with existing weed control tactics to achieve adequate glyphosate-resistant Palmer amaranth control, where applicable.
Download or read book Glyphosate resistant Palmer Amaranth amaranthus Palmeri in Arkansas written by Griff Michael Griffith and published by . This book was released on 2013 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since 2000, there have been thirteen weed species confirmed resistant (R) to glyphosate in the United States, six of those resistant species are present in Arkansas. The goal of this research was to confirm and to determine the level of resistance in two R Palmer amaranth biotypes from Mississippi (MC-R) and Lincoln (LC-R) Counties, Arkansas, and one susceptible (S) biotype from Clarendon County, South Carolina, which had never been exposed to glyphosate. Shikimic acid concentration over time was significantly greater in the S biotype than both the MC-R and LC-R biotypes. The lethal dose required to kill 50% (LD50) of the population was 2,255 and 3,223 g ae ha -1 for the MC-R and LC-R biotypes, respectively, and it was hypothesized that the two Arkansas biotypes each had a different resistance mechanism. Results indicate metabolism of glyphosate to its major metabolite, aminomethylphosphonic acid (AMPA), was not responsible for resistance in any biotype. Reduced absorption in the LC-R and limited translocation from the treated leaf in the MC-R were at least partially responsible for the observed resistance to glyphosate. The LC-R biotype effectively colonized a field within two years of a single resistant female producing ̃20,000 seed. Cotton lint yield was reduced over 100 kg ha-1 by some densities of LC-R Palmer, depending on the soil and relative elevation in that region. Several resistant management options exist in cotton; however, results indicate that timely herbicide applications based off of Palmer amaranth size are required for effective season-long control and management of the soil seedbank.
Download or read book Physiological Basis of Herbicide Interaction and Integrated Management of Palmer Amaranth Amaranthus Palmeri written by Ivan Bernardo Cuvaca and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Palmer amaranth is a major threat to many cropping systems in the USA. As a result of selection, Palmer amaranth has evolved resistance to at least six herbicide modes of action including microtubule-, 5-enolpyruvylshikimate-3-phosphate synthase-, acetolactate synthase-, photosystem II-, hydroxyphenylpyruvate dioxygenase-, and protoporphyrinogen oxidase- inhibitors. Dicamba is effective for Palmer amaranth control; however, extensive use of this herbicide increases the likelihood of evolution of resistance to dicamba. The overall objective of this dissertation was to investigate the physiological basis of interaction of herbicides with different modes of action in Palmer amaranth control and evaluate use of integrated approaches to manage Palmer amaranth in field conditions. The specific objectives were to: 1) evaluate the effect of plant height on dicamba efficacy to control Palmer amaranth; 2) investigate the mechanism of resistance to glyphosate in a Palmer amaranth accession from Kansas, and evaluate efficacy of glyphosate and dicamba tank-mix to control this accession; 3) investigate the physiological basis of glyphosate and dicamba interaction in tank-mix to control Palmer amaranth; 4) determine the efficacy of reduced dicamba use on Palmer amaranth control in irrigated corn production; and 5) investigate grain sorghum and Palmer amaranth growth and reproductive attributes in response to sorghum density and nitrogen rate under irrigated conditions. All experiments were repeated and appropriate statistical tests were used for data analyses. The results indicate: a) increased absorption and translocation of dicamba contribute to increased efficacy to control Palmer amaranth at early growth stage; b) tank mixing glyphosate and dicamba had a synergistic effect on Palmer amaranth control; c) rapid absorption of dicamba and increased translocation of glyphosate resulted in increased Palmer amaranth control when applied in combination; d) there is an opportunity to maintain grain yield while effectively controlling Palmer amaranth in irrigated corn with the integration of increased corn plant population density and reduced dicamba application and e) integrating sorghum plant population and nitrogen did not suppress Palmer amaranth in irrigated sorghum, although sorghum grain yield was maintained. The outcome of this dissertation provides several strategies to improve control of Palmer amaranth.
Download or read book Integrated Weed Management for Sustainable Agriculture written by Robert Zimdahl and published by Burleigh Dodds Series in Agric. This book was released on 2017-12-14 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt: Weeds remain a major obstacle to improved yields in agriculture. At the same time, established methods of control are being undermined by problems such as herbicide resistance. This major collection reviews key developments in integrated weed management (IWM) to manage weeds more sustainably.
Download or read book Genetically Engineered Crops written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2017-01-28 with total page 607 pages. Available in PDF, EPUB and Kindle. Book excerpt: Genetically engineered (GE) crops were first introduced commercially in the 1990s. After two decades of production, some groups and individuals remain critical of the technology based on their concerns about possible adverse effects on human health, the environment, and ethical considerations. At the same time, others are concerned that the technology is not reaching its potential to improve human health and the environment because of stringent regulations and reduced public funding to develop products offering more benefits to society. While the debate about these and other questions related to the genetic engineering techniques of the first 20 years goes on, emerging genetic-engineering technologies are adding new complexities to the conversation. Genetically Engineered Crops builds on previous related Academies reports published between 1987 and 2010 by undertaking a retrospective examination of the purported positive and adverse effects of GE crops and to anticipate what emerging genetic-engineering technologies hold for the future. This report indicates where there are uncertainties about the economic, agronomic, health, safety, or other impacts of GE crops and food, and makes recommendations to fill gaps in safety assessments, increase regulatory clarity, and improve innovations in and access to GE technology.
Download or read book Physiological Ecology of North American Plant Communities written by Brain F. Chabot and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although, as W.D. Billings notes in his chapter in this book. the development of physiological ecology can be traced back to the very beginnings of the study of ecology it is clear that the modern development of this field in North America is due in the large part to the efforts of Billings alone. The foundation that Billings laid in the late 1950s came from his own studies on deserts and subsequently arctic and alpine plants, and also from his enormous success in instilling enthusiasm for the field in the numerous students attracted to the plant ecology program at Duke University. Billings' own studies provided the model for subsequent work in this field. Physiological techniques. normally confined to the laboratory. were brought into the field to examine processes under natural environmental conditions. These field studies were accompanied by experiments under controlled conditions where the relative impact of various factors could be assessed and further where genetic as opposed to environmental influences could be separated. This blending of field and laboratory approaches promoted the design of experiments which were of direct relevance to understanding the distribution and abundance of plants in nature. Physiological mechanisms were studied and assessed in the context of the functioning of plants under natural conditions rather than as an end in itself.
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 Herbicide Resistant Crops written by Stephen O. Duke and published by CRC Press. This book was released on 2018-01-18 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: Edited by a recognized leader in the field, Herbicide-Resistant Crops is the first book to cover all of the issues related to the controversial topic of herbicide-resistant crops. It provides extensive discussions of the modern biotechnological methods that have been used to develop such crops, and reviews the implications - both positive and negative - of developing crops that are resistant to herbicides. The creation and anticipated applications of specific herbicide-resistant crops are also discussed. In addition, the book covers the potential impact of herbicide-resistant crops on weed management practices and the environment, and presents issues related to the regulation and economics of these crops. The editor has brought together a diverse group of professionals, representing the several distinct areas impacted by the new technology of herbicide-resistant crops. The wide range of viewpoints presented in this book creates a balanced and complete survey, providing a notable contribution to the literature.
Download or read book Herbicides written by Andrew Price and published by BoD – Books on Demand. This book was released on 2015-11-26 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: Herbicides are one of the most widely used groups of pesticides worldwide for controlling weedy species in agricultural and non-crop settings. Due to the extensive use of herbicides and their value in weed management, herbicide research remains crucial for ensuring continued effective use of herbicides. Presently, a wide range of research continues to focus on improved herbicide use and weed biology. The authors of Herbicides, Agronomic Crops and Weed Biology cover multiple topics concerning current valuable herbicide research.
Download or read book Steel in the Field written by Greg Bowman and published by . This book was released on 1997 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Decision Support Systems for Weed Management written by Guillermo R. Chantre and published by Springer Nature. This book was released on 2020-07-31 with total page 341 pages. Available in PDF, EPUB and Kindle. Book excerpt: Weed management Decision Support Systems (DSS) are increasingly important computer-based tools for modern agriculture. Nowadays, extensive agriculture has become highly dependent on external inputs and both economic costs, as well the negative environmental impact of agricultural activities, demands knowledge-based technology for the optimization and protection of non-renewable resources. In this context, weed management strategies should aim to maximize economic profit by preserving and enhancing agricultural systems. Although previous contributions focusing on weed biology and weed management provide valuable insight on many aspects of weed species ecology and practical guides for weed control, no attempts have been made to highlight the forthcoming importance of DSS in weed management. This book is a first attempt to integrate `concepts and practice’ providing a novel guide to the state-of-art of DSS and the future prospects which hopefully would be of interest to higher-level students, academics and professionals in related areas.
Download or read book Mobile DNA written by Douglas E. Berg and published by Amer Society for Microbiology. This book was released on 1989-01 with total page 972 pages. Available in PDF, EPUB and Kindle. Book excerpt: Documents the remarkable mobility of DNA in procaryotic and eucaryotic genomes: the ability of various DNA segments to move to new sites, to invert, and to undergo deletion or amplification, generally without the extensive DNA sequence homology needed for classical recombination. Seventy contributors explore the mechanisms of these rearrangements, how they are regulated, their biological consequences, and their potential use as research tools. For students and researchers of molecular genetics. Annotation copyrighted by Book News, Inc., Portland, OR
Download or read book Biological Resources and Migration written by Dietrich Werner and published by Springer Science & Business Media. This book was released on 2004-06-09 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Migration of humans and animals, plants and even microbes is a ubiquitous global phenomenon. This book covers all forms of migration - plant, microbial, animal or human - and their mutual impact in detail. The contributions in this book are the result of an innovative International Conference and OECD Workshop aimed at triggering off the interdisciplinary dialogue between natural scientists and socioeconomists.
Download or read book Herbicide Classes in Development written by Peter Böger and published by Springer. This book was released on 2011-09-23 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemical pest control is in use in practically every country in the world since agrochemicals play a decisive role in ensuring food supply and protection against damage by pests, insects and pathogenic fungi. Particularly in the half century since World War II, food production has risen dramatically in most parts of the world. In the last 20 years, the yield of major crops has roughly doubled in Western agriculture and there is still the potential for further achievements, particularly in the developing countries. The world's cereal and rice production, now more than 2 billion tons/year, has to increase by 2. 4% annually to cope with the rising food demand caused mainly by the growing population and improvement of living standards in most of the developing countries. Such a demand for food has to be achieved by higher yields from the restricted arable land already in use. Global farm land resources are about 1. 4 billion ha, of which 1. 2 billion ha is cultivated with major crops. Experts agree that a future substantial addition of new produc tive areas is unlikely. Those with a high yield potential are already in use; new fields with a lower output may possibly be obtained by cultivation of arid or cold areas. More recently, new areas of large-scale farmland have been devel oped in tropical regions of Latin America, primarily in Argentina and Brazil, at the cost of the destruction of tropical rain forest.
