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1.
Altered target sites as a mechanism of herbicide resistance 总被引：4，自引：0，他引：4
Over 200 distinct herbicide resistant weed biotypes have evolved worldwide. In most of these, resistance is conferred by an altered target site, i.e. a modified target protein with reduced affinity for the herbicide(s) in question. This has been documented for herbicides that target most major known sites of action, including those that inhibit photosynthetic electron transfer at photosystem II, acetyl-CoA carboxylase, acetolactate synthase, and tubulin polymerization. Patterns of cross-resistance to structurally similar herbicides and those from other chemical classes that target the same site vary, depending on the mutation and its effect on protein steric and electronic properties. Mechanisms of target site-based herbicide resistance are reviewed, with emphasis on the biochemical and molecular basis for resistance. 相似文献
2.
Iñigo Loureiro Enrique Rodríguez-García Concepción Escorial José María García-Baudín José Luis González-Andújar María Cristina Chueca 《Crop Protection》2010
Lolium rigidum is the most prevalent and damaging grass weed of winter cereals in Spain. L. rigidum infestations are frequently treated with herbicides and, consequently, populations have evolved resistance. The objective of this study was to determine the extent and frequency of herbicide resistance in L. rigidum populations in Spain to the selective herbicides chlortoluron, diclofop-methyl and chlorsulfuron, commonly used for its control in-crop, and to glyphosate. The response to these herbicides was evaluated on 123 accessions surveyed randomly across cereal cropping areas of the regions of Castile and León, Catalonia and Andalusia. The fresh weight and the frequency of undamaged plants were calculated for each accession and herbicide. At the regional level, higher frequencies of accessions displaying resistance occurred in Catalonia, an intensively cropped region with a greater herbicide selection pressure. Of concern is that in this region the 60% of the accessions displayed some level of resistance to the ALS-inhibiting herbicide chlorsulfuron. The 6.9% of the accessions found in Castile and León with some resistance to glyphosate could also indicate an incipient problem of resistance to this herbicide. For the other herbicides and regions the majority of the accessions remained susceptible. The possible mechanisms of herbicide resistance development in L. rigidum accessions (target-site versus non-target-site resistance) and their variation among regions was discussed. This study can be used to generate herbicide resistance-management schemes for farmers, based upon the herbicide the site and the potential for resistance development. 相似文献
3.
Wild oat (Avena fatua L.) is the most troublesome weed in cereal crops in Argentina. With the aim of studying the effects of different herbicides, doses, and wild oat growth stage at application on weed control and crop yield, field experiments were conducted in wheat and barley crops during three growing seasons in the south of Buenos Aires Province, Argentina. Treatments were post-emergence applications of new herbicide, pinoxaden + cloquintocet mexyl (5%-1.25%), at doses that ranged from 20 g to 60 g a.i. pinoxaden ha−1, applied at two to three leaves and the beginning of tillering of wild oat. In addition, standard treatments were included and applied at the same wild oat growth stages. Diclofop methyl at 511 g a.i. ha−1 and fenoxaprop-p-ethyl at 55 g a.i. ha−1 were applied in barley. In wheat, diclofop methyl was replaced by clodinafop-propargyl + cloquintocet mexyl (24%-6%) at 36 g a.i. clodinafop-propargyl + 9 g cloquintocet mexyl ha−1 and in 2008/09 wheat experiments, iodosulfuron plus metsulfuron methyl (5%-60%) at 3.75 g a.i. ha−1 + 3 g a.i. ha−1 also was included. In both crops, pinoxaden at 30 g a.i. ha−1 and at higher rates, fenoxaprop-p-ethyl and clodinafop-propargyl gave the best control of wild oat. In 2006/07 wheat crops, treatments applied at tiller initiation provided better control than the early timing averaged across herbicides. However, wheat yield generally was greater with early application. In barley, wild oat control and crop yield were similar regarding time of application. Variations in crop yield were correlated with grain number m−2 both in wheat and barley, but relationships between both grain number and spikes m−2 and with grains per spike were identified only in wheat. 相似文献
4.
A bioeconomic model is described and used to investigate the agronomic and economic consequences of using a range of management strategies for the control of winter wild oats (Avena sterilis L.) in cereal cropping systems representative of central Spain. The results of simulations indicated that growing winter wheat continuously with the annual application of herbicides may be the optimum strategy, resulting in acceptable wild oat populations and maximum economic benefits. However, the practice of wheat monoculture was only a valid option as long as herbicides were applied annually: spraying herbicides in alternate years failed to control wild oats adequately and resulted in major economic losses. The rotation of wheat with a fallow year, with no herbicides applied in either of the two years, may be a satisfactory low-cost alternative when wild oat infestation levels are low, but it is not valid when infestation levels are high. The strategy that combines the use of a fallow year with herbicide application in the wheat year resulted in optimum wild oat control and moderate profitability under all conditions. However, the net returns obtained were substantially lower than in the continuous wheat plus herbicide strategy. The sensitivity of the model to variation in various key parameters was tested: wheat yield level and fixed costs were the two parameters that had the largest effect on model output. In general, the effect of changing parameter values was more pronounced in continuous wheat systems than in wheat-fallow rotations 相似文献
5.
Site-specific weed management implies detecting the location of weeds in order to generate maps of their spatial distribution. This information facilitates a more accurate application of herbicides, spraying them in the exact areas of weed growth and in the required doses. In order to explore the potential of commercial satellites to discriminate and map weeds, we used the information contained in high spatial resolution images acquired by the QuickBird satellite to assess the density of sterile oat (Avena sterilis) present in a winter barley field at two different dates (March and June). Our results confirmed the potential of using satellite images in the spectral discrimination of weed patches in infested fields. The results of binary logistic regressions showed that the best matches in the classification of three categories (low, medium, or high sterile oat densities) corresponded to the March image. QuickBird’s March image provided reliable estimates of sterile oat patches in barley crops when weed density was relatively high (between 86% and 94% of agreement between predicted and observed densities). However, when weed densities were lower than 10 plants/m2 there were serious difficulties to distinguish them from weed-free zones (between 72 and 75% of global agreement in the classification) with large underestimation of medium density weed patches (10 plants/m2). This is a potential limitation considering than the thresholds used for herbicide application decisions are generally close to this density. However, the information obtained may still be useful for producing field maps to describe the spatial distribution of this weed. Moreover, these studies have provided valuable information on the best spectral regions and/or vegetation indices for approaching discrimination between sterile oat and cereal crops and the most suitable period for it. 相似文献
6.
Phalaris paradoxa is a competitive grass commonly found in durum wheat crops of central and southern Italy. Among the 85 populations screened from 1998 to 2008 for resistance to ACCase-inhibitors and graminicide sulfonylureas, 17 resulted as being resistant to at least one ACCase inhibitor while none of the populations showed resistance to sulfonylureas. ACCase resistance in hood canary-grass seems to be spreading rather slowly in Italy. Out of the 17 populations, seven were characterised through outdoor dose-response pot experiments to investigate resistance levels and cross-resistance patterns to ACCase-inhibitors and multiple resistance to other mode of action. Molecular bases of resistance to the recently introduced DEN herbicide pinoxaden were also investigated. Six populations were confirmed to be ACCase-resistant with various cross-resistance patterns. Two populations were resistant to all tested ACCase herbicides, with pinoxaden resistance indexes (RI) based on survival ranging from 22 to 50. The two populations have been molecularly characterised for resistance to pinoxaden. A single point-mutation in the ACCase gene was identified in each population, causing the amino-acid substitutions of Ile1781Val and Asp2078Gly in 0478L and 0025, respectively. The results suggest that resistance of P. paradoxa to pinoxaden is due to an altered target site and different mutations cause different resistance levels. The biological characteristics of the species, mainly self-pollinated, and the absence of multiple resistance allow herbicides with different modes of action to be used for controlling ACCase-resistant populations. Chemical tools should be carefully used within integrated weed management strategies. 相似文献
7.
WANG Guangda GAO Peng YANG Wenyan CUI Ao ZHAO Jianhua FENG Zhiming CAO Wenlei CHEN Zongxiang ZUO Shimin 《中国水稻科学》1986,34(4):316-324
【Objective】Cultivating herbicide resistant rice varieties is an important direction in rice breeding. Developing efficient functional markers can accelerate the screening of herbicide resistance trait. 【Method】dCAPS and KASP techniques were used to analyze the genotypes of the experimental materials. In addition, the phenotypes were identified by herbicide spraying test. 【Result】Through sequence alignment analysis, we further confirmed that the mutation of 627 amino acid of acetolactate synthase (ALS) gene from serine (S) into asparagine (N) in Jinjing 818 (here after named ALS627N) produces strong resistance to imidazolinone herbicides. According to the DNA sequence flanking the mutation site, we developed two novel functional markers, dC-ALS-627 and K-ALS-627, for detecting this resistant allele ALS627N. The two markers can effectively distinguish homozygous ALS627N type, heterozygous type and homozygous wild type. Combined with herbicide spraying test, we confirmed that ALS627N is a dominant herbicide resistant gene. 【Conclusion】 We validated that the two markers have great potential in marker-assisted breeding for ALS627N gene. Totally, this study will accelerate the development of new varieties with resistance to imidazolinone herbicides, and have significance in breeding practice. 相似文献
8.
【目的】培育抗除草剂品种是水稻育种中的一个重要方向,开发高效的功能标记可以加快抗除草剂性状的筛选工作。【方法】利用开发的dCAPS和KASP分子标记对试验材料的基因型分型,另结合除草剂喷施试验进行表型鉴定。【结果】测序结果验证了前人发现的金粳818中乙酰乳酸合成酶（acetolactate synthase,ALS）基因第627位氨基酸由丝氨酸（serine,S）突变为天冬酰胺（asparagine,N）是其抗咪唑啉酮类除草剂的主要原因,本文将其命名为ALS627N。根据此变异位点的DNA序列差异,开发了两个新的功能标记dC-ALS-627和K-ALS-627,可有效区分ALS627N纯合型、杂合型及非突变纯合型。【结论】两个标记均可以广泛用于ALS627N基因的标记辅助选择育种,有助于加快培育抗咪唑啉酮类除草剂新品种,具有重要的实际应用价值。 相似文献
9.
Red rice is the main weed in rice paddy fields. Imidazolinone herbicides in resistant rice cultivars currently provide a unique opportunity to control red rice in large-scale rice fields. However, the continuous use of this technology has resulted in imidazolinone-resistant red rice biotypes. This study aimed to identify the mechanism of herbicide resistance and the frequency and spatial distribution of the known imidazolinone herbicide-resistant alleles in red rice. The nucleotide sequence of the ALS gene indicated that the G654E, S653D and A122T mutations are present in the imidazolinone herbicide-resistant rice cultivars IRGA 422 CL, SATOR CL and PUITÁ INTA CL, respectively. This information and the nucleotide sequence surrounding these mutations were used for the development of single nucleotide polymorphism (SNP) molecular markers to identify the possible mutations that confer herbicide resistance in red rice. This analysis was carried out in a total of 481 plants from 38 populations collected as individuals that escaped control with the herbicides imazethapyr and imazapic in rice paddy fields in Southern Brazil. The G654E mutation was the most frequent, being found in 100% and 90.9% of the populations in the 2006/2007 and 20007/2008 seasons, respectively. In addition, the S653D and A122T mutations were also present either alone or as double or triple mutations in some plants. Target site insensitivity is the predominant mechanism of resistance in red rice resistant to imidazolinone herbicides in Southern Brazil. The high frequency of the S653D mutation, the same mutation responsible for the resistance in the rice cultivar largely used in Southern Brazil, indicates that gene flow is occurring from the rice cultivar to red rice. Management practices related to increasing crop sanitation and decreasing of herbicide selection pressure through crop rotation should be enforced to prevent the evolution of herbicide resistance in red rice. 相似文献
10.
Cyperus difformis L. is one of the worst weeds of rice world-wide and has evolved resistance to acetolactate synthase (ALS)-inhibiting herbicides in rice fields of California. Propanil use was intensified to control the widespread resistant biotypes. Rice growers have recently experienced poor control, suggesting resistance to this photosystem II-inhibiting herbicide may have evolved in C. difformis populations. The objectives of this study were to detect the presence of propanil resistance, to establish resistance levels, and to investigate involvement of enhanced herbicide detoxification as mechanism of resistance through the use of metabolic inhibitors. Four C. difformis populations collected in rice fields from the Sacramento Valley of California were confirmed resistant to propanil. This is the first case of such resistance outside the Poaceae and the first time C. difformis exhibits resistance to an herbicide mechanism of action other than ALS inhibition. Carbaryl and malathion applied individually in mixture with propanil had minor effects on herbicide toxicity suggesting metabolic detoxification was not a resistance mechanism. A resistant biotype produced more than 80% biomass after a propanil (6.7 kg a.i. ha−1) and carbaryl (1.9 kg a.i. ha−1) or propanil and malathion (1.0 kg a.i. ha−1) treatment compared to <20% by a susceptible biotype, suggesting substantial resistance still persisted in spite of insecticide addition. Propanil-resistant plants were cross-resistant to bensulfuron-methyl, imazosulfuron, halosulfuron-methyl and penoxsulam, but susceptible to carfentrazone. The loss of propanil to control this important weed of rice underscores the fragility of herbicide-based weed control in monoculture rice. Integrated weed management approaches to decrease herbicide selection pressure are needed to mitigate the evolution of multiple-herbicide resistance in C. difformis of California rice. 相似文献
11.
黑龙江省稻稗对丁草胺的抗性测定及交互抗性的研究 总被引：1，自引：0，他引：1
【目的】明确黑龙江省水田稻稗(Echinochloa oryzicola Vasing)对丁草胺的抗药性水平以及对其他细胞分裂抑制剂的交互抗药性水平。【方法】采用琼脂法和整株盆栽法测定了黑龙江省14个地区53个田块的稻稗对丁草胺的抗药性以及对其他3种细胞分裂抑制剂丙草胺、苯噻酰草胺和莎稗磷的交互抗性。【结果】琼脂法检测出庆安03、东京城镇02等4个稻稗生物型对丁草胺产生了中等水平抗性,抗性指数为12.92~26.03,占供试稻稗生物型的7.55%;兴隆镇03、阿城04等4个稻稗生物型对丁草胺产生了低等水平抗性,抗性指数为6.63~8.86,占供试稻稗生物型的7.55%;庆安01、汤原01等5个稻稗生物型对丁草胺敏感性下降,抗性指数为3.18~4.84,占供试稻稗生物型的9.43%;其余阿城02、尚志02等40个稻稗生物型对丁草胺表现敏感,抗性指数均小于3,占供试稻稗生物型的75.47%。选取上述测定结果当中抗性最高的两个生物型,使用整株盆栽法进行对丁草胺的抗性水平验证。发现庆安03和东京城镇02同样产生了中等水平抗性,抗性指数分别为16.78和13.27;同时测定两个抗性生物型对丙草胺、苯噻酰草胺和莎稗磷3种细胞分裂抑制剂的交互抗性,结果显示,庆安03稻稗生物型对丁草胺和丙草胺产生了交互抗性;东京城镇02稻稗生物型对丁草胺、丙草胺和莎稗磷产生了交互抗性。【结论】黑龙江省部分地区稻稗对丁草胺产生了抗药性,且对丙草胺和莎稗磷产生了交互抗性。 相似文献
12.
【目的】明确黑龙江省水田稻稗(Echinochloa oryzicola Vasing)对丁草胺的抗药性水平以及对其他细胞分裂抑制剂的交互抗药性水平。【方法】采用琼脂法和整株盆栽法测定了黑龙江省14个地区53个田块的稻稗对丁草胺的抗药性以及对其他3种细胞分裂抑制剂丙草胺、苯噻酰草胺和莎稗磷的交互抗性。【结果】琼脂法检测出庆安03、东京城镇02等4个稻稗生物型对丁草胺产生了中等水平抗性，抗性指数为12.92~26.03，占供试稻稗生物型的7.55%；兴隆镇03、阿城04等4个稻稗生物型对丁草胺产生了低等水平抗性，抗性指数为6.63~8.86，占供试稻稗生物型的7.55%；庆安01、汤原01等5个稻稗生物型对丁草胺敏感性下降，抗性指数为3.18~4.84，占供试稻稗生物型的9.43%；其余阿城02、尚志02等40个稻稗生物型对丁草胺表现敏感，抗性指数均小于3，占供试稻稗生物型的75.47%。选取上述测定结果当中抗性最高的两个生物型，使用整株盆栽法进行对丁草胺的抗性水平验证。发现庆安03和东京城镇02同样产生了中等水平抗性，抗性指数分别为16.78和13.27；同时测定两个抗性生物型对丙草胺、苯噻酰草胺和莎稗磷3种细胞分裂抑制剂的交互抗性，结果显示，庆安03稻稗生物型对丁草胺和丙草胺产生了交互抗性；东京城镇02稻稗生物型对丁草胺、丙草胺和莎稗磷产生了交互抗性。【结论】黑龙江省部分地区稻稗对丁草胺产生了抗药性，且对丙草胺和莎稗磷产生了交互抗性。 相似文献
13.
Recent Advances in Development of Herbicide Resistant Transgenic Hybrid Rice in China 总被引：3，自引：0，他引：3
XIAO Guo-ying 《水稻科学》2009,16(3):235-239
In addition to weed control in direct seeding field of hybrid rice, herbicide resistance genes were used by Chinese scientists to increase and identify the purity of hybrid seeds, and to realize the mechanization of hybrid seed production. The elite restorer lines, such as Minghui 63, R752, T461, R402, D68 and E32 were transformed directly with herbicide resistance genes, in which D68 and E32 are restorer lines of two-line system and the others are of three-line system. Because almost all of important restorer lines are indica varieties and are recalcitrant in transformation, many herbicide resistant near-isogenic restorer lines were developed by sexual hybridization of indica and japonica varieties and backcross with indica restorer lines later, such as Ce 64, Minghui 63, Teqing, Milyang 46, R402 and 9311, in which 9311 is a restorer line of two-line system. The elite photoperiod-sensitive/thermo-sensitive genic male sterile lines, such as Pei'ai 64S, P88S, 4008S and 7001S, were transformed with herbicide resistance genes. A few herbicide resistant male sterile lines were developed through sexual hybridization and subsequently systemic selection, such as Bar1259S, Bar2172S, 05Z221A and 05Z227A. With the employment of herbicide resistant male sterile lines or herbicide resistant restorer lines, a few herbicide resistant hybrid rice combinations were developed, such as Xiang 125S/Bar 68-1 and Pei'ai 64S/Bar 9311. Based on herbicide resistance, the research was marching on to investigate the parental lines of hybrid rice with insect resistance, drought tolerance, etc. 相似文献
14.
15.
大豆抗除草剂资源筛选 总被引：1，自引：0，他引：1
通过三年的大田和分栽试验，研究了２０００多份大豆对绿黄隆和阿特拉津的抗性反应。结果表明，不同大豆对绿黄隆的抗性反应差异较大，多数材料抗性很差，没有发现具有高度抗性，可用于理论研究或育种实践的材料，不同大豆对阿特拉津的抗性在苗期存在差异，但绝大多数材料在第一复叶未展开前即死掉，仅有极少数材料能结荚，而荚又很少。用常规方法筛选抗绿黄隆的材料是有希望的，筛选抗阿特拉津的材料及为困难。 相似文献
16.
Rick S. Llewellyn Robert K. Lindner David J. Pannell Stephen B. Powles 《Crop Protection》2002,21(10):1067-1075
In Australian grain-growing regions, the evolution of weeds resistant to multiple herbicides threatens the sustainability of existing cropping systems. As a result, herbicide susceptibility is considered to be a potentially exhaustible resource. Based on a survey of 132 Western Australian grain growers, perceptions of various factors relating to the herbicide resource were measured. These include the rate of resistance evolution, cost of resistance, the future availability of replacement herbicides, reductions in the level of resistance in a population over time, and mobility of resistance. Growers were found to have a generally high level of awareness of herbicide resistance and consider it to have a high potential cost. However, many perceive that the stock of effective herbicides is likely to be renewed in the short term, either through new herbicide development or resistance reversion. Potential opportunities for targeted extension to improve farmer decision-making are identified. 相似文献
17.
Rita Redaelli Viviana Del Frate Silvia Bellato Giovanna Terracciano Roberto Ciccoritti Christoph U. Germeier Ester De Stefanis Daniela Sgrulletta 《Journal of Cereal Science》2013
A growing interest in oat (Avena ssp.) soluble fibre (β-glucan) is related to its role in the promotion of human health, and to its utilization in the production of functional foods with increased health benefits. Genetic variability and environmental conditions can exert significant effects on the grain β-glucan content. In this study 658 European oat genotypes grown in different environments in 2008 or 2009 within the European Project “Avena genetic resources for quality in human consumption” were analysed for total β-glucan content; the soluble fraction of β-glucan was also determined in a sub-set of 165 samples. Total β-glucan content ranged from 2.85 to 6.77% d.m. and the soluble fraction from 2.05 to 5.29% d.m. The estimated percentage of the soluble fraction ranged from 50.7 to 87.0%. β-glucan content and solubility were significantly influenced by both genotype and growing environment. Hierarchical cluster analysis allowed accessions with similar β-glucan compositions to be grouped. The accessions with the highest contents of both fractions included Avena sativa varieties from several countries and wild species. Finally, the data obtained were used to develop a NIRS calibration equation to predict the contents of total and soluble β-glucan in both naked and husked genotypes. 相似文献
18.
The objectives of this study were to describe the intra-specific variation in herbicide response of weed populations when subjected to new vs. well-established herbicides, and to assess distributions of logLD50- and logGR50-estimates as a potential indicator for early resistance detection. Seeds of two grass weeds (Alopecurus myosuroides, Apera spica-venti) were collected in southern Sweden, mainly in 2002. In line with the objectives of the study, the collections sites were not chosen for noted herbicide failures nor for detected herbicide resistance, but solely for the presence of the target species. For each species, seedlings were subjected to two herbicides in dose-response experiments in a greenhouse. One herbicide per species was recently introduced and the other had been on the market for control of the species for a decade, with several reports of resistance in the literature. Fresh weight of plants and a visual vigour score were used to estimate GR50 and LD50, respectively. Resistance to fenoxaprop-P-ethyl in A. myosuroides was indicated by the LD50-estimates to be present in frequencies sufficient to affect the population-level response in 9 of 29 samples, and was correlated to response to flupyrsulfuron, while low susceptibility to isoproturon in A. spica-venti populations was not linked to the response to sulfosulfuron. In the study as a whole, the magnitude of the estimated herbicide susceptibility ranges differed irrespective of previous exposure. No consistent differences were found in the distribution of LD50-estimates for new and “old” herbicides, and normality in the distribution of estimates could not be assumed for a non-exposed sample, even in the absence of an indication of cross-resistance. 相似文献
19.
Field resistances of nine accessions of common wild rice (Oryza rufipogon Griff.) and one rice variety (IR24) were evaluated by using nine strains of bacterial blight pathogen (Xanthomonas oryzae pv. oryzae) from the Philippines. IR24 was highly susceptible to all the strains, and six common wild rice accessions resisted all the nine strains, with a resistance frequency of 67%. The accessions Yulin and Wanning were only susceptible to PXO280 and PXO71, respectively. The accession Gaozhou was susceptible to the three strains PXO79, PXO99 and PXO339, whereas resistant to the other six strains. It could be concluded that there is at least one resistance gene in each common wild rice accession. The functional markers of the genes xa5, xa13, Xa21 and Xa27 were used to detect the presence of these resistance genes in the nine tested wild rice accessions, and it was found that four wild rice accessions contained heterozygous xa13. Among the nine common wild rice accessions, five were homozygous for Xa27 and three homozygous for xa27, and the accession Laibin contained neither xa27 nor Xa27. In addition, there were no xa5 and Xa21 in all of these accessions. 相似文献
20.
A purported drawback to the use of transgenic herbicide-resistant crops is the fear that the crop or interbreeding wild relatives will become weedy. It has been posited that a change even in a single trait can confer weediness. This hypothesis was tested with Brachypodium distachyon. This innocuous species came into contact with herbicides through the use of crushed rock from its habitat for road foundations. It evolved s-triazine resistance and developed as a monoculture. When true weeds later evolved simazine resistance, B. distachyon was partially competed from the ecosystem and then disappeared upon the use of non-triazine herbicides. Thus, this wild species remained a weed only until true weeds evolved resistance or until other herbicides were used. One gene mutation did not convert it into a weed, which implies that this will be equally improbable in other cases, when the gene codes for an otherwise neutral trait such as herbicide resistance. 相似文献