Download or read book Effects of Phosphorus on Italian Ryegrass Lolium Multiflorum Lam Growth and Alternative Herbicide Management for Diclofop resistant Italian Ryegrass in Winter Wheat Triticum Aestivum L written by Trinidad María Pérez-Fernández and published by . This book was released on 1999 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2000 with total page 956 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Chlorsulfuron on Diclofop methyl Toxicity to Italian Ryegrass Lolium Multiflorum and Italian Ryegrass Interference in Wheat Triticum Aestivum written by Rex Allan Liebl and published by . This book was released on 1985 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effectiveness of Diclofop for Control of Italian Ryegrass Lolium Multiflorum in Winter Wheat Triticum Aestivum written by Edward L. Robinson and published by . This book was released on 1983 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effectiveness of Diclofop for Control of Italian Ryegrass Lolium Multiflorum in Winter Wheat Triticum Aestivum written by E. L. Robinson and published by . This book was released on 1983 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Selected Herbicides on Italian Ryegrass Lolium Multiflorum and Returns from Hard Red Winter Wheat Triticum Aestivum written by Matthew Austin Barnes and published by . This book was released on 1999 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Italian Ryegrass Lolium Multiflorum Control in Imidazolinone tolerant Wheat Triticum Aestivum Under the Direction of Dr Alan York written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Italian ryegrass is the most problematic weed of small grains in North Carolina. This weed has traditionally been controlled in wheat with diclofop. However, after many years of continuous use, much of the Italian ryegrass in the state is now resistant to diclofop. A field experiment was conducted at three locations to determine control of Italian ryegrass and response of imidazolinone-tolerant wheat to imazamox and other herbicides. Imazamox ammonium salt applied POST in the fall to 3- to 4-leaf Italian ryegrass at 35 to 53 g ae/ha controlled Italian ryegrass 90 to 100% 10 weeks after treatment. Late-season control ranged from 83 to 98% at two locations and 24 to 55% at the third location. Late-season control from spring-applied imazamox on 1- to 3-tiller ryegrass ranged from 53 to 58% at one location and 7 to 16% at the other locations. Split application of imazamox at 27 g/ha in the fall and 27 g/ha in the spring was less effective than fall-applied imazamox at 53 g/ha at two of three locations. However, split application was more effective than spring application. Fall-applied imazamox was less effective than fall-applied diclofop on diclofop-susceptible Italian ryegrass but more effective on mixed populations of diclofop-resistant and -susceptible biotypes. Pendimethalin applied PRE at 1120 g ai/ha increased late-season control 10 to 33 percentage points when used in combination with fall-applied imazamox at 35 g/ha. Imazethapyr ammonium salt at 70 g ae/ha was less effective than imazamox, while imazethapyr at 47 g/ha plus imazapyr isopropylamine salt at 16 g ae/ha and imazamox were similarly effective. Imazapic ammonium salt at 70 g ae/ha and imazamox at 53 g/ha were similarly effective at two locations, while imazapic was more effective at the third location. Imidazolinone herbicides caused only minor, temporary chlorosis on the wheat. In greenhouse experiments, a diclofop-susceptible biotype of Italian ryegrass was more sensitive to imazamox than a diclofop-
Download or read book Influence of Lime on Italian Ryegrass Control in Winter Wheat with Five Herbicides written by Engin Ozdilek and published by . This book was released on 1978 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liming has been shown to increase the activity of certain soil-applied herbicides. One research worker reported improved weed control with diuron after lime had increased soil pH levels. This could be caused by improved competitive ability of the wheat, greater availability of the herbicide, or a combination of the two factors, Field studies were conducted at two locations to determine the effect of three lime rates on wheat growth alone, on ryegrass growth alone, and on ryegrass control from five herbicides. Lime rates were 0, 4.5, and 9.0 t/ha, giving an approximate pH range from 5. 0 to 6.1. Herbicides used were trifluralin, triallate, diclofop, rnetribuzin, and diuron, each applied at three rates. Diuron at eight rates was also studied in the greenhouse at five rates of lime. All of the herbicides in the field studies caused large increases in wheat grain yield when compared to untreated ryegrass-infested wheat. However, liming had no effect on ryegrass growth nor activity of the herbicides and, except in one case, no effect on wheat growth. The high rate of metribuzin, 1.12 kg/ha, caused severe wheat injury at one location but only minor injury at the other. The other herbicides caused little or no injury even at double the commercial rate. In one greenhouse experiment, application of lime increased ryegrass growth but did not affect diuron activity. In the other experiment, lime alone did not influence ryegrass growth but tended to increase diuron activity at the 4.5 t/ha lime rate. The application of lime is not expected to have wide-spread effects on weed control in winter wheat in western Oregon, at least with the five herbicides tested in these studies.
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 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 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 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 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 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 Weed Biology and Management written by Inderjit and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt: Weeds hold an enigmatic and sometimes-controversial place in agriculture, where they are generally reviled, grudgingly tolerated, and occasionally admired. In most cases, growers make considerable effort to reduce the negative economic impact of weeds because they compete with crops for resources and hinder field operations, thereby affecting crop productivity and quality, and ultimately the sustainability of agriculture. Weed control in production agriculture is commonly achieved through the integration of chemical, biological, and mechanical management methods. Chemicals (herbicides) usually inhibit the growth and establishment of weed plants by interfering with various physiological and biochemical pathways. Biological methods include crop competition, smother crops, rotation crops, and allelopathy, as well as specific insect predators and plant pathogens. Mechanical methods encompass an array of tools from short handled hoes to sophisticated video-guided robotic machines. Integrating these technologies, in order to relieve the negative impacts of weeds on crop production in a way that allows growers to optimize profits and preserve human health and the environment, is the science of weed management.
Download or read book The Effect of Soil Factors on Glyphosate Availability in Soil written by Michael Ken Kawate and published by . This book was released on 1986 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: Glyphosate (N-(phosphonomethyl)glycine) is an effective foliar-applied herbicide with broad-spectrum activity. Greenhouse and laboratory experiments were conducted to determine the importance of soil moisture, autoclaved soil, soil type, sphagnum peat, soil pH, added phosphorus, and plant residues on crop establishment and growth when glyphosate was applied before emergence of the crop. Glyphosate was applied preemergence with a track-mounted sprayer in 281 or 374 L/ha spray volume. Counts and fresh weights were taken to determine the effect of the glyphosate application. Radiolabelled glyphosate was used to determine Freundlich adsorption isotherms for Chehalis, Crooked, and Semiahmoo-2 soils at various pH or phosphorus levels. Glyphosate application to sandy soils (Chehalis and Crooked) reduced fresh weight of Italian ryegrass (Lolium multiflorum Lam.), whereas application to finer-textured soils seldom caused plant injury, indicating that soil texture may be an important factor. Also, on Chehalis and Crooked soils, increasing the soil pH caused increased injury to Italian ryegrass, suggesting that more glyphosate was available at higher soil pH. This was confirmed in an adsorption study using radiolabelled glyphosate. Other interactions also should be considered. The incidence of damping-off (Pythium spp.) was higher on plants grown in glyphosate-treated Chehalis soil than plants grown in untreated soil. Barnyardgrass (Echinochloa crusgalli (L.) Beauv.) and Italian ryegrass were injured by a preemergence application of glyphosate to sphagnum peat. However, glyphosate application to muck (organic) soils did not injure bioassay species. These results suggest that nondecomposed organic matter does not render glyphosate unavailable, and therefore, caution is advised when applying glyphosate to media with sphagnum peat or other nondecomposed plant material. Adjusting soil moisture, autoclaving soil, or adding phosphorus did not influence glyphosate availability in soil. Dead or dying perennial ryegrass residues, whether chemically treated or not, reduced fresh weight of Italian ryegrass seedlings. Roots or whole plant residues were more inhibitory than shoots. Increasing the time interval between treating perennial ryegrass and planting Italian ryegrass reduced phytotoxicity to Italian ryegrass. Adding fertilizer to pots to alleviate competition for nutrients did not prevent the phytotoxic effect of perennial ryegrass residues. Experiments exposing ryegrass seedling roots or shoots to various concentrations of glyphosate, in the absence of soil, showed that roots were damaged more than shoots when roots were treated with glyphosate. However, roots and shoots were injured equally when shoots were treated with glyphosate, indicating that glyphosate is readily translocated to the roots. Italian ryegrass and bentgrass (Agrostis tenuis Sibth. 'Highland') were more sensitive to glyphosate applied preemergence than crimson clover (Trifolium incarnatum L.), alfalfa (Medicago sativa L.), and tomato (Lycopersicon esculentum Mill. 'Bonny Best'). Glyphosate activity in soil varied considerably from one study to another, suggesting that a particular factor, or combination of factors has not been identified. But, soil activity did occur, hence, precautions should be taken when applying glyphosate preplant or preemergence to: a) light-textured soils; b) limed soils; c) potting media with sphagnum peat; and d) areas with high weed densities (plant residues). One precaution could be to increase the time interval between treatment and planting to reduce the possibility of glyphosate or phytotoxin injury because microorganisms would have more time to degrade glyphosate or phytotoxins.
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.
