Download or read book Evaluating Commercial Cultivars and Farm collected Biotypes of Italian Ryegrass lolium Perenne L Ssp Multiflorum lam Husnot for Potential Herbicide Resistance in Georgia written by Danielle Burke Simmons and published by . This book was released on 2017 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: Italian ryegrass [Lolium perenne ssp. multiflorum (Lam.) Husnot] is known for being the most troublesome weed in small grains in Georgia. This Lolium species is also a highly recommended cool-season forage that becomes problematic when total control is never achieved in warm-season bermudagrass or tall-fescue hayfields. Concerns about the lack of control in Italian ryegrass require Georgia populations be evaluated. Therefore, the response of Italian ryegrass populations to small grain herbicides was assessed. Greenhouse experiments from 2015 to 2017 indicate that post-emergence use herbicides lack control of some Georgia commercialized Italian ryegrass cultivars and farm-collected biotypes. A continuation of these experiments within the field setting are needed to determine if the responses can be replicated, and further analyses on other ryegrass populations should be conducted to determine if these trends are developing in experimental seed lots and currently available populations.

Download or read book Control of Italian Ryegrass Lolium Perenne L Spp Multiflorum Lam Husnot in Wheat Triticum Spp and Evaluation of Resistance to Acetyl CoA Carboxylase Inhibiting Herbicides written by and published by . This book was released on 2009 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: Control of Italian ryegrass is important to Tennessee wheat producers. Control of Italian ryegrass has become more difficult over the years due to diclofop resistance. Italian ryegrass resistance to diclofop has been documented in several countries including the US. Tennessee producers have begun to notice that ryegrass escapes are becoming more prevalent than in years past. The purpose of this research was to use glasshouse methods to screen selected populations of Italian ryegrass for resistance to diclofop and to a more recent wheat herbicide pinoxaden and to utilize field experiments to develop herbicide programs for control Italian ryegrass in the field. Resistance to diclofop was found in eight TN populations. The eight populations did not show cross-resistance to pinoxaden. One population from Union County, NC (R1) was found to be resistant to both diclofop and pinoxaden. The level of resistance to pinoxaden of the R1 population was 14 x that of the susceptible population. Field experiments demonstrated preemergence (PRE) Italian ryegrass control with chlorsulfuron (71 to 94%) and flufenacet + metribuzin (84 to 96%). Italian ryegrass control with pendimethalin applied PRE or delayed preemergence (DPRE) was variable (0 to 85%). Postemergence control of Italian ryegrass was good with pinoxaden, mesosulfuron, flufenacet + metribuzin, and chlorsulfuron + flucarbazone (>80%). Timing of application and herbicide treatment had no effect upon wheat yield, except for diclofop and pendimethalin treatments where Italian ryegrass was not controlled. Pinoxaden is in the phenylpyrazolin herbicide family which offers control of Italian ryegrass but is not toxic to wheat. Pinoxaden has only been on the market for three years yet several wheat producers have suspected resistance in Italian ryegrass biotypes. An experiment was conducted to identify Italian ryegrass biotypes resistant to pinoxaden and to determine the mechanism of resistance using derived Cleaved Amplified Polymorphic Sequence (dCAPS) methods. Two populations were found resistant to pinoxaden, one from the state of Washington (R2) and the other from North Carolina (R1). The substitution of isoleucine by leucine at the 1781 ACCase residue was identified in the R1 biotype but not in the R2. The NC1 biotype is the first known pinoxaden resistant Italian ryegrass population to be documented having the 1781 target-site mutation.

Download or read book Distribution and Control of Herbicide Resistant Italian Ryegrass Lolium Perenne L Ssp Multiflorum Lam Husnot in Winter Wheat Triticum Aestivum L in North Carolina written by Zachary Ryan Taylor and published by . This book was released on 2015 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Distribution and Control of Herbicide resistant Italian Ryegrass Lolium Perenne L Ssp Multiflorum Lam Husnot in Arkansas written by James Walker Dickson and published by . This book was released on 2012 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: Italian ryegrass populations have evolved resistance to herbicides that producers rely on for weed control both in wheat and burn-down. The objectives of this research were to: test populations of Italian ryegrass from across Arkansas for resistance to glyphosate, diclofop, pinoxaden, and pyroxsulam; determine if there were any differences in control of 12 glyphosate-resistant populations in relation to glyphosate rate or application timing; determine the level of glyphosate resistance in one selected population versus a susceptible standard and a previously discovered glyphosate-resistant population; and determine the best options for controlling Italian ryegrass prior to planting crops. A total of 215 population samples were tested. On average 17% of the samples were resistant to glyphosate, 95% were resistant to diclofop, 64% were resistant to pyroxsulam, and 12% were resistant to pinoxaden. A few were resistant to all four chemistries tested. Control of glyphosate-resistant populations was improved with the high rate of glyphosate at the three- to four-tiller growth stage; however, results for individual populations were variable. When averaged across populations, no rate or timing of glyphosate controlled these resistant populations greater than 62%. One population was found to be 23 times more tolerant to glyphosate than a susceptible standard. Three field experiments were conducted for Italian ryegrass control in the spring, in no-till production in the fall, and following fall tillage. Herbicide applications in the spring were unsuccessful, especially when glyphosate is not an option. Even when postemergence (POST) treatments visually controlled ryegrass at least 80%, enough ryegrass residue remained that would cause problems with spring tillage, planting, and overall crop stand establishment. In the fall-tilled study, the residual herbicides flumioxazin plus S-metolachlor, S-metolachlor, clomazone, and pyroxasulfone applied immediately following fall tillage reduced Italian ryegrass biomass by 83 to 95% at 200 days after treatment.

Download or read book Herbicide Resistance Mechanism s in Italian Ryegrass Lolium Perenne Ssp Multiflorum Populations in the Southern United States written by Reiofeli Algodon Salas and published by . This book was released on 2012 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: Italian ryegrass is a principal weed problem in wheat production fields in the southern US. Resistance to herbicides diclofop, mesosulfuron, and pinoxaden among ryegrass populations has been reported. Glyphosate-resistant Italian ryegrass populations were identified in Desha County, Arkansas. This research aimed to 1) determine resistance patterns to ACCase (diclofop and pinoxaden) and ALS (imazamox, mesosulfuron, and pyroxsulam) herbicides among Italian ryegrass populations from the southern US; 2) determine if cytochrome P450-mediated enhanced herbicide metabolism contributed to resistance; and 3) elucidate the resistance mechanism to glyphosate in four Arkansas populations (Des03, Des05, Des14, and D8). For objective 1, 30 accessions from problematic fields in the southern US between 2008 and 2010 were subjected to dose-response bioassays. Among the 30 accessions, 27 were resistant to both diclofop and mesosulfuron, 25 of which were also resistant to pyroxsulam. Ten Arkansas accessions collected in 2008 were resistant to diclofop, mesosulfuron, pyroxsulam, and imazamox. One accession from Georgia and three accessions from North Carolina were resistant to diclofop, mesosulfuron, pyroxsulam, and pinoxaden. For objective 2, six ryegrass populations with different resistance patterns to glyphosate, ALS- and ACCase herbicides, were treated with P450 inhibitors malathion (1000 g ai ha-1) and 1-aminobenzotriazole (100 microM ABT) before herbicide application. Malathion improved herbicide activity in some populations, but did not completely overcome resistance to any herbicide. This indicates that P450-mediated metabolism is only partially responsible for resistance in these populations. For objective 3, plants from Des03 population were analyzed for resistance level, EPSPS genetic mutation(s), EPSPS enzyme activity, and EPSPS gene copy number. The absorption and translocation of 14C-glyphosate were similar in R and S plants. The EPSPS gene in the R plants did not contain any point mutation(s) associated with glyphosate resistance. Resistance to glyphosate in Des03 is due to increased basal EPSPS enzyme activity resulting from amplification of the EPSPS gene. Follow-up experiments conducted on other glyphosate-R populations, Des05, Des14, and D8, showed 11-fold to 516-fold more copies of the EPSPS gene in resistant plants than their susceptible counterparts indicating that EPSPS gene amplification also confers resistance to glyphosate in these populations.

Download or read book The Ryegrasses written by Harry August Schoth and published by . This book was released on 1940 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evolution of Herbicide Resistance in Lolium Perenne Ssp Multiflorum Populations written by Elizabeth Karn and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Herbicide-resistant weeds provide a unique system in which to study the evolution of adaptive traits. The selection pressures, adaptive traits, and often the underlying basis for herbicide resistance are typically known, allowing for studies of adaptive variation across large agricultural landscapes that vary in selection pressures and intensities over space and time. In the last several years, populations of Lolium perenne ssp. multiflorum (Lam.) in orchards and vineyards of northwest California were suspected of evolving resistance to the herbicides glyphosate and glufosinate. Earlier work identified that a non-synonymous mutation in 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene is responsible for glyphosate resistance in the Central Valley of California. The research presented in this dissertation characterizes phenotypes resistant to glyphosate and glufosinate and examines the evolution of glyphosate resistance in northwest California populations of L. perenne ssp. multiflorum using neutral genetic diversity and adaptive genetic variation, to gain a greater understanding of contemporary adaptive evolution across landscapes. In Chapter 1, I measure the frequency of glyphosate-resistant and glufosinate-resistant individuals in 14 populations of L. perenne across three screening times and measure the population-average level of resistance in selected populations. The analysis demonstrates that while both glyphosate- and glufosinate-resistant individuals are present in northwest California with distinct mechanisms conferring resistance to each herbicide, these resistance phenotypes are variable over time, especially for glufosinate. In Chapter 2, using microsatellite genetic variation at 12 loci in the sampled individuals, I show that California L. perenne contains high genetic diversity and admixture across populations, with a potential for spread of glyphosate resistance through gene flow. In Chapter 3, I genotype adaptive genetic variation in the sampled individuals and identified four distinct glyphosate-resistant EPSPS alleles at codon site 106, indicating multiple evolutionary origins of glyphosate resistance in the region, although resistance in some populations cannot be explained by EPSPS mutations at site 106. Together, these results demonstrate that the evolution of adaptive traits across a landscape can be quite complex, with variable phenotypes conferred by multiple independent evolutionary origins of the same adaptive trait with subsequent spread through gene flow.

Download or read book A Survey of Italian Ryegrass Lolium Multiflorum Herbicide Resistance in Northern Idaho and Eastern Washington written by Seth A. Gersdorf and published by . This book was released on 2009 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multiple resistant Italian Ryegrass Lolium Perenne Spp Multiflorum Populations in Oregon written by Mingyang Liu and published by . This book was released on 2013 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: Italian ryegrass (Lolium perenne spp. multiflorum) is a common weed management problem in turfgrasses, cereals and non-crop areas in the United States. In Oregon, the number of populations with multiple-resistance continues to increase. To manage these resistant populations, the resistance patterns must be determined. In this study, five Italian ryegrass populations (CT, R1, R2, R3 and R4) from two cropping systems were studied for resistance patterns and mechanisms. The CT population is from a Christmas tree plantation and was resistant to at least six herbicides with four different mechanisms of action: atrazine, diuron (2.4-fold), glyphosate (7.4-fold), hexazinone (3.1-fold), imazapyr (1.8-fold), and sulfometuron. The resistant indices (RI) for sulfometuron and atrazine could not be calculated because 50% growth reduction for the CT population was not reached even with the highest rates applied, 17.6 kg ai ha−1and 16 kg ai ha−1, respectively, which are 16 times the recommended field application rates for this two herbicides. The CT population accumulated less shikimate than the S population. There were two mutations in the CT population, Trp591 to Leu in the ALS gene and Ser264 to Gly in the psbA gene, which explain the ALS and PII cross resistance, respectively. R1, R2, R3 and R4 were collected from annual cropping systems. All four populations were resistant to flufenacet. RIs for two populations, R2 and R4, were 8.4 and 5.9, respectively. R2 and R4 also were resistant to mesosulfuron-methyl, pinoxaden, quizalofop and clethodim. R4 was resistant to diuron, but R2 was not. An Asp-2078-Gly substitution in the ACCase gene was found in both R2 and R4 populations, while another Ile-2041-Asn substitution in the ACCase gene was found in the R4 population. These mutations explain the ACCase cross resistance in the R2 and R4 populations. The mechanisms for the glyphosate resistance in the CT population and the flufenacet resistance in R1, R2, R3 and R4 populations were not identified in this study. None of the five populations were resistant to the herbicide pyroxasulfone.

Download or read book Ecology Production and Management of Lolium for Forage in the USA written by Francis Marion Rouquette and published by American Society of Civil Engineers. This book was released on 1997 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Characterization of Herbicide Resistance in Lolium Multiflorum Populations from California and Oregon written by Caio Augusto De Castro Grossi Brunharo and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Italian ryegrass (Lolium multiflorum) is a troublesome weedy species spread throughout the United States, competing for light, water and nutrients with crops. Its control has been chiefly dependent on herbicides due to their effectiveness and practicality. As result of heavy selection pressure, herbicide-resistant populations of Italian ryegrass have been selected in California and Oregon trees and vines. Recently, poor control of Italian ryegrass with paraquat was reported by orchard managers in California, whereas glufosinate-resistant populations were reported in Oregon. We hypothesize that the low paraquat efficacy observed in a California population is due to the selection of a paraquat-resistant biotype. We also hypothesized that non-target-site mechanisms of resistance were selected in glufosinate-resistant Italian ryegrass populations from Oregon. Greenhouse, field and laboratory experiments were carried out to characterize herbicide-resistant Italian ryegrass populations from California. Laboratory experiments were conducted to characterize the resistance to glufosinate in Oregon Italian ryegrass populations. Greenhouse dose-response experiments confirmed the presence of paraquat resistance in an Italian ryegrass population from California, with multiple resistance to clethodim and glyphosate. Glyphosate resistance is due to amino acid substitutions in the EPSPS at position 106. Field experiments with PRE herbicides indicated that tankmixes containing indaziflam and flumioxazin can provide adequate L. multiflorum control up to 150 days after treatment. Resistance to paraquat likely involves vacuolar sequestration of the herbicide. Laboratory experiments with Oregon Italian ryegrass populations indicate that metabolism of glufosinate is involved in the resistance mechanism. These results add generally to the body of knowledge of herbicide resistance in ryegrass and should influence how multiple herbicide-resistant populations are managed in trees and vines of the western US.

Download or read book Crop Rotation on Organic Farms written by Charles L. Mohler and published by Natural Resource Agriculture and Engineering Service (Nraes). This book was released on 2009 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Wheat Improvement Management and Utilization written by Ruth Wanyera and published by BoD – Books on Demand. This book was released on 2017-05-24 with total page 396 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Wheat Improvement, Management, and Utilization book covers some of the most recent research areas that touch on enhancement of wheat productivity. It is obvious that wheat is one of the major staple crops grown globally. This crop has widely been researched on considering that, for instance, it is afflicted by various abiotic and biotic stresses that limit its growth and productivity. Today?s goal of wheat improvement consistently is to develop varieties that are high yielding with good processing and technological qualities, well adapted and tolerant to prevailing biotic and abiotic stresses. Therefore, this is a valuable reference book on wheat improvement, agronomy, and end-use qualities, particularly for those who work in research organizations and higher academic institutions. Moreover, it provides an invaluable resource for readers interested in a quick review of trending topics in wheat.

Download or read book IPM for Shrubs in Southeastern U S Nursery Production written by Matthew Chappell and published by . This book was released on 2016-06-30 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: IPM for Shrubs in Southeastern US Nursery Production Volume II is the third book released by the Southern Nursery Integrated Pest Management Working Group (SNIPM). The first two books are available for download as chapter .pdf files at http://wiki.bugwood.org/SNIPM and as an eBook from the iTunes Bookstore https://itunes.apple.com/us/book/ipm-for-select-deciduous-trees/id541182125?mt=11 and https://itunes.apple.com/us/book/ipm-for-shrubs-in southeastern/id903114207?mt=11

Download or read book Fundamentals of Weed Science written by Robert Zimdahl and published by Academic Press. This book was released on 2012-12-02 with total page 465 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fundamentals of Weed Science provides an introduction to the basic principles of weed science for undergraduate courses. It discusses several aspects of weed biology and control, and traces the history of herbicide development. The book begins with an introduction to weeds, covering their definition, characteristics, harmful aspects, and the cost of weed control. This is followed chapters on weed classification, the uses of weeds, weed biology, weed ecology, allelopathy, the significance of plant competition, weed management and control methods, and biological weed control. Later chapters deal with herbicidesthe most important weed control tools and the ones with the greatest potential for untoward effects. Students of weed science must understand herbicides and the factors governing their use as well as the potential for misuse. These chapters discuss chemical weed control, the properties and uses of herbicides, factors affecting herbicide performance, herbicide application, herbicide formulation, ecological impact of herbicides, pesticide registration and legislation, weed management systems, and the future of weed science.

Download or read book 2017 Southeastern U S Pest Control Guide for Nursery Crops and Landscape Plantings written by Joseph C. Neal and published by NC State Extension. This book was released on 2017-04-30 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This pest control guide is a project of the Southern Nursery IPM Working Group (SNIPM) and collaborators. Featuring 25 tables and 14 graphs, this guide provides up to date information about pest control products used in nursery crops and ornamental landscape plantings in the southeast. It is a quality resource on its own or as a supplement to more comprehensive integrated pest management (IPM) manuals for trees and shrubs. This publication and more comprehensive IPM manuals are available in free downloadable PDF versions from the SNIPM web site at https: //wiki.bugwood.org/SNIPM.

Download or read book Weeds of California and Other Western States written by Joseph M. DiTomaso and published by UCANR Publications. This book was released on 2007 with total page 979 pages. Available in PDF, EPUB and Kindle. Book excerpt: This encyclopedic yet easy-to-use 2-volume set covers 262 individual entries, including a full description of 451 species and another 361 plants compared as similar species, representing 63 plant families. 13 shortcut identification tables for groups that share similar, unusual, or relatively uncommon characteristics. 2 grass identification keys - a key to all characteristics including inflorescences and reproductive parts and a key to vegetative characteristics only. 67 tables comparing important characteristics of difficult-to-distinguish weedy species. Color photos of over 700 weeds including seeds, seedlings, flowers, and mature plants. Appendix of non-native plants rarely or occasionally naturalized in California. Glossary of botanical terms. Bibliography of some of the most pertinent publications. Index to common names, scientific names, and synonyms. Each entry describes the plant category, family name, common name, and synonyms along with a summary of the important aspects of the plant’s life cycle, size, growth form, impact, method of introduction, and toxicity. You'll also find a description of the seedling, mature plant, roots and underground structures, flowers, fruits and seeds, spikelets and florets, spore-bearing structures, and post senescence characteristics for each entry. Also includes a description of the habitat where each is typically found and distribution in California, other states, and worldwide, along with maximum elevation at which the species is found. Rounding out each entry is a description of the methods of reproduction, seed dispersal, germination requirements and conditions, seed survival and longevity, early establishment characteristics and requirements, cultural practices and management options that have proven effective or ineffective in controlling infestations, and a notation of the species' inclusion on federal or state noxious weed lists.