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 Herbicide Resistance in Weeds Early Detection Mechanisms Dispersal New Insights and Management Issues written by Ilias Travlos and published by Frontiers Media SA. This book was released on 2020-10-28 with total page 329 pages. Available in PDF, EPUB and Kindle. Book excerpt: This eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contact.
Download or read book Herbicide Resistance in Weeds and Crops written by Zvonko Pacanoski and published by BoD – Books on Demand. This book was released on 2017-10-04 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Herbicides are the dominant technology and the most effective weed control tools ever developed that are used for the control of weeds that infest crops. Over the last several decades, in situations of intense herbicide usage, there have been many examples of the evolution of weed populations resistant to herbicides. Weed adaptations to management tactics, including biochemical mimicry in the form of evolved resistance to the herbicides used for weed control, have increased rapidly throughout agriculture and now threaten global food security. Nowadays, expended space of research activities remains to focus on the herbicide resistance to weeds and crops. The authors of Herbicide Resistance in Weeds and Crops cover various issues regarding the present relevant research.
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 Multiple Herbicide Resistant Weeds and Non target Site Resistance Mechanisms A Global Challenge for Food Production written by Joel Torra and published by Frontiers Media SA. This book was released on 2021-12-20 with total page 174 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 Investigation of Inheritance of Glyphosate Resistance and the Mechanisms of Glufosinate Resistance in Italian Ryegrass Lolium Perenne L Spp Multiflorum Lam Husnot Populations written by Wilson Vidal Avila Garcia and published by . This book was released on 2011 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: Italian ryegrass populations have been identified with evolved resistance to glyphosate in orchards with a history of glyphosate use. Two of these populations were selected to investigate the inheritance of glyphosate resistance. The mechanisms involved in the herbicide resistance were an altered target site for the population SF and reduced herbicide translocation for the population OR1. Mendelian inheritance studies and dose response experiments were conducted on the two populations. Four F1 families were formed by reciprocal crosses between each of the glyphosate resistant populations (SF and OR1) and the susceptible population (S) C1. Eight backcross families (BC1) were formed between the F1 individuals from each family and the susceptible population C1. Most of the F1 families resulting from SF and C1 had susceptible:resistant ratios of approximately 1:1. Similar trends were observed in the backcross families concluding that glyphosate resistance due to target site mutation in the SF Italian ryegrass population is likely conferred by a single, nuclear, partially-dominant gene. For population OR1, there was significant variation in the susceptible:resistant ratios in the F1 families. Chi-square analysis for backcross families failed to fit the model for a single major gene suggesting that the glyphosate resistance due to reduced herbicide translocation in the Italian ryegrass population OR1 is multigenic. Italian ryegrass glyphosate resistant populations OR1, OR2, and OR3, the population MG, and three susceptible populations C1, C2, and C3 were selected to conduct dose-response experiments, ammonia accumulation assays, and enzymatic studies to quantify their sensitivity to glufosinate. The glufosinate rates required to reduce the growth by 50% (GR50) were 0.15, 0.18, and 0.21 kg ai ha−1 for the susceptible populations C1, C2, and C3, respectively, and for the resistant populations OR1, OR2, OR3, and MG, the GR50 values were 0.49, 0.42, 0.40, and 0.45 kg ai ha−1 respectively, resulting in an average resistance index of 2.4. The same trend was observed in ammonia accumulation studies between 48 and 96 hours after glufosinate treatment. The susceptible populations accumulated between 1.5 to 2.5 times more ammonia than the resistant populations. The glufosinate concentration required to reduce glutamine synthetase enzyme activity by 50% (I50) was not different for the resistant OR1, OR2, and OR3 and susceptible populations. However, a different response was observed for the population MG. The I50 values ranged from 3.1 to 3.6 uM for the resistant populations OR1, OR2, and OR3, and from 3.7 to 4.3 uM for the susceptible populations. The population MG had an I50 of 10.7 uM resulting in a resistant ratio 2.6-fold higher than the average of the control populations C1 and C2. Eighty-three percent of the plastidic GS gene from the resistant population MG and the susceptible C1 was cloned and sequenced. One amino acid substitution was found in the population MG that may be responsible for the reduced enzyme sensitivity. These results are the first reports of target site and non target site based glufosinate resistance in a weed species.
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 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 Glyphosate resistance in Italian Ryegrass Lolium Multiflorum Evaluation and Investigation of the Mechanisms of Resistance written by Alejandro Perez-Jones and published by . This book was released on 2007 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt: A suspected glyphosate-resistant Italian ryegrass (Lolium multiflorum ) (OR) population was collected from a filbert (Corylus avellana L.) orchard near Portland, OR. Based on the dose-response experiments conducted in the greenhouse, it was found that the suspected glyphosate-resistant population was approximately fivefold more resistant to glyphosate than the susceptible (S) population. Furthermore, it was found that the S population accumulated between three and five times more shikimic acid than the OR population, confirming its resistance to glyphosate. The mechanisms conferring glyphosate resistance in two glyphosate-resistant L. multiflorum populations, one from Oregon, USA (OR), and one from Chile (SF), were also studied. Based on a Petri dish dose-response bioassay, the OR and the SF populations were two and fivefold more resistant to glyphosate when compared to the S population, respectively; however, based on a whole-plant dose-response bioassay, both OR and SF populations were fivefold more resistant to glyphosate than the S population. The S population accumulated two and three times more shikimic acid in leaf tissue 96 h after glyphosate application than the glyphosate-resistant OR and SF populations, respectively. There were no differences between the S and the glyphosate-resistant OR and SF populations in 14C-glyphosate leaf uptake; however, the patterns of 14C-glyphosate translocation were significantly different. In the OR population, a greater percentage of 14C-glyphosate absorbed by the plant moved distal to the treated section and accumulated in the tip of the treated leaf. In contrast, in the S and in the SF populations, a greater percentage of 14C-glyphosate moved to the untreated leaves and the stem. cDNA sequence analysis of the EPSP synthase gene indicated that the SF population has a proline 106 to serine amino acid substitution, which has been previously shown to confer moderate levels of glyphosate resistance. We confirmed glyphosate resistance in two different L. multiflorum populations, and found that they have different mechanisms of resistance. The OR population has limited glyphosate translocation while the SF population has a mutation of the EPSP synthase gene.
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 Weed Control written by Nicholas E. Korres and published by CRC Press. This book was released on 2018-12-19 with total page 664 pages. Available in PDF, EPUB and Kindle. Book excerpt: In light of public concerns about sustainable food production, the necessity for human and environmental protection, along with the evolution of herbicide resistant weeds, call for a review of current weed control strategies. Sustainable weed control requires an integrated approach based on knowledge of each crop and the weeds that threaten it. This book will be an invaluable source of information for scholars, growers, consultants, researchers and other stakeholders dealing with either arable, row, cash, vegetables, orchards or even grassland-based production systems. The uniqueness of this book comes from the balanced coverage of herbicide effects on humans and environment in relation to best weed control practices of the most important cropping systems worldwide. Furthermore, it amalgamates and discusses the most appropriate, judicious and suitable weed control strategies for a wide range of crops. It reviews the available information and suggests solutions that are not merely feasible but also optimal.
Download or read book Weed Science and Weed Management in Rice and Cereal Based Cropping Systems 2 Volumes written by Aurora M. Baltazar and published by John Wiley & Sons. This book was released on 2023-03-29 with total page 1145 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book presents discussions on: Biology and ecology of major troublesome weeds infesting rice, wheat, corn, soybean, focusing on different cropping patterns in both tropical and temperate cropping systems and science-based weed management practices involving chemical, non-chemical, biological, integrated methods. Herbicides used, with their most recent classification, identification of new target sites, mechanisms and modes of action and how and why weeds evolve resistance to herbicides. New concepts, new paradigms and new technologies to manage evolution of resistance to herbicides including weed genomics, bioherbicides and allelochemicals. Highly recommended for students, teachers, researchers, agronomists, horticulturists, crop physiologists, and crop protection specialists in tropical and temperate agricultural systems, particularly in areas where major tropical weeds are posing potential threats to temperate agricultural systems.
Download or read book Management Strategies for Glyphosate resistant Italian Ryegrass Lolium Perenne L Ssp Multiflorum Lam Husnot written by Robin Christa Bond and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Glyphosate-resistant (GR) Italian ryegrass has been documented in many different countries around the world and has now become a major problem in row crop production areas of Mississippi. Field experiments were conducted from 2006 to 2008 in the Mississippi Delta to evaluate various herbicide and tillage treatment programs for its control. Highest level of control and reduction of GR Italian ryegrass biomass was observed with mechanically incorporated as well as surface applied residual herbicides in the fall of the year. Control of GR Italian ryegrass was 86-95% with surface applications of clomazone at 0.56, 0.84, and 1.12 kg ai/ha, s-metolachlor at 1.79 kg ai/ha and KIH-485 at 0.16 kg ai/ha 171 days after emergence. Using a systems approach, preplant incorporated (PPI) clomazone and/or s-metolachlor followed by preemergence (PRE) application of paraquat + linuron+ non-ionic surfactant was also found to control and reduce biomass of GR Italian ryegrass.
Download or read book Glyphosate Resistance and Tolerance in Italian Ryegrass Lolium Perenne Spp Multiflorum written by Robert Chase MacPherran and published by . This book was released on 2015 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annual ryegrass, or Italian ryegrass (Lolium perenne spp. multiflorum), has been the most stable, in terms of acres, grass produced for the past 25 years in Oregon. Increased interest in Italian ryegrass as a cover crop has increased demand for quality seed. Ideal Italian ryegrass cover crop cultivars are named cultivars, have winter hardiness and uniform germination, emergence, and growth to guarantee effective termination and reduce the potential for volunteer carryover. The typical method of cover crop termination is through chemical means with a non-selective herbicide or with tillage. In this study, nine termination treatments were used to determine effective treatments and explore potential differences in control between a diploid and a tetraploid cultivar. There was no difference in response based on ploidy level between the treatments. Glyphosate and glyphosate tank mixtures effectively controlled Italian ryegrass. A cultivar evaluation was also conducted to determine if there was a difference in response to glyphosate between ploidy levels. There was no difference in response to glyphosate due to ploidy level. Shikimate acid assays did suggest possible differences in the amount of glyphosate binding to EPSPS depending on the cultivar. An Italian ryegrass population (OR10) was found to be glyphosate resistant. Along with screening the OR10 suspected resistant population, samples collected from seed production fields were collected and screened. No glyphosate resistant populations were found.
Download or read book Seed Testing written by Sabry Gobran Elias and published by . This book was released on 2012 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: An essential reference for students, seed technologists, researchers, and seed industry personnel, this comprehensive guide outlines the most widely performed modern seed quality tests, explores the principles behind them, the history of seed testing, why seeds are tested and when, and sampling, sub-sampling, seed laboratory management, accreditation, and seed quality assurance programs. The authors describe statistical applications to seed testing and tolerances, and they provide a detailed morphological and structural description of seed formation and development. The book examines the testing of genetic traits and transgenic seeds, including DNA and protein genetic purity tests, and cultivar purity identification for conventional seeds. In addition to the most common seed purity and viability tests, tests for seed and seedling vigor, seed-borne diseases and seed moisture determination are also discussed.
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.
