• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Molecular Genetics of Herbicide Resistance in Palmer Amaranth (Amaranthus palmeri): Metabolic Tembotrione Resistance and Geographic Origin of Glyphosate Resistance
【24h】

Molecular Genetics of Herbicide Resistance in Palmer Amaranth (Amaranthus palmeri): Metabolic Tembotrione Resistance and Geographic Origin of Glyphosate Resistance

机译：Palm菜（Amaranthus palmeri）中除草剂抗性的分子遗传学：代谢性滕康酮抗性和草甘膦抗性的地理起源

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Palmer amaranth (Amaranthus palmeri) is a major weed in U.S. cotton and soybean production systems, partly because it evolved resistance to five different herbicide modes of action. Resistance to the 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibitor tembotrione in a population from Nebraska (NER) is due to enhanced metabolism. This type of non-target-site resistance is especially troublesome because of its potential for cross-resistance. Tembotrione-susceptible (NES) and NER formed the same tembotrione metabolites but NER exhibited faster 4-hydroxylation followed by glycosylation. The T50 value (time for 50% production of the maximum 4-hydroxylation product) was 4.9 and 11.9 h for NER and NES, respectively. Hydroxylation is typically catalyzed by cytochrome P450 monooxygenases (CYPs). Metabolism differences between NER and NES were most prominent under 28 °C conditions and herbicide application at the four-leaf stage. An RNA-Seq transcriptome analysis was conducted with Pseudo-F2 tembotrione-resistant and -susceptible individuals originating from three separate NER x NES crosses that were sampled before, six, and twelve h after treatment (HAT). Differential gene expression analysis identified CYP72A219 and CYP81E8 as strong candidates for metabolic resistance. The contigs were constitutively expressed in resistant plants, as were the contigs for several glycosyltransferases (GTs), oxidase, and glutathione-S-transferase (GST). Exposure to tembotrione further increased their expression in both resistant and susceptible plants.;Originally native to the Southwest, A. palmeri has spread throughout the country. In 2004 a population was identified with resistance to glyphosate, a herbicide heavily relied on in modern no-tillage and transgenic glyphosate-resistant crop systems. Glyphosate resistance in the species is now highly prevalent in USA and was also discovered in Brazil in 2015. This was confirmed by species identification with a genetic marker, dose-response studies, shikimate accumulation assay, and EPSPS copy number assay. The Brazilian population was also resistant to sulfonylurea and imidazolinone ALS inhibitor herbicides conferred by two different alleles for target-site mutations in the ALS gene (W574L and S653 N). The degree of genetic relatedness among eight different populations of glyphosate-resistant (GR) and -susceptible (GS) A. palmeri from various geographic regions in USA was investigated by analyzing patterns of phylogeography and diversity to ascertain whether resistance evolved independently or spread from outside to an Arizona locality (AZ-R). Shikimate accumulation and EPSPS genomic copy assays confirmed resistance or susceptibility. With a set of 1,351 single nucleotide polymorphisms (SNPs), discovered by genotyping-by-sequencing (GBS), UPGMA phylogenetic analysis, principal component analysis, Bayesian model-based clustering, and pairwise comparisons of genetic distances were conducted. A GR population from Tennessee and two GS populations from Georgia and Arizona were identified as genetically distinct while the remaining GS populations from Kansas, Arizona, and Nebraska clustered together with two GR populations from Arizona and Georgia. Within the latter group, AZ-R was most closely related to the GS populations from Kansas and Arizona followed by the GR population from Georgia. GR populations from Georgia and Tennessee were genetically distinct from each other. The data suggest the following two possible scenarios: either glyphosate resistance was introduced to the Arizona locality from the east, or resistance evolved independently in Arizona. Glyphosate resistance in the Georgia and Tennessee localities most likely evolved separately. Thus, modern farmers need to continue to diversify weed management practices and prevent seed dispersal to mitigate herbicide resistance evolution in A. palmeri.
机译：er菜（Amaranthus palmeri）是美国棉花和大豆生产系统中的主要杂草，部分原因是它演变成对五种不同除草剂作用方式的抗性。内布拉斯加州（NER）人群对4-羟苯基丙酮酸双加氧酶（HPPD）抑制剂替莫三酮的耐药性是由于新陈代谢增强所致。这种类型的非目标站点电阻特别麻烦，因为它具有交叉电阻的潜力。 Tembotrione敏感（NES）和NER形成相同的Tembotrione代谢产物，但NER表现出更快的4-羟基化，随后发生糖基化。 NER和NES的T50值（产生最大4-羟基化产物的50％的时间）分别为4.9和11.9 h。羟基化通常由细胞色素P450单加氧酶（CYP）催化。 NER和NES之间的代谢差异在28°C条件下和四叶期施用除草剂时最为明显。用抗假性F2 tembotrione耐药和易感个体进行RNA-Seq转录组分析，这些个体来自三个单独的NER x NES杂交，分别在治疗前，治疗后六小时和十二小时取样（HAT）。差异基因表达分析确定CYP72A219和CYP81E8为代谢抗性的强候选者。重叠群在抗性植物中组成性表达，几种糖基转移酶（GTs），氧化酶和谷胱甘肽-S-转移酶（GST）的重叠群也是如此。暴露于替康三酮进一步提高了它们在抗性和易感植物中的表达。；棕榈原产于西南地区，已遍布全国。 2004年，人们确定了对草甘膦具有抗性的种群，草甘膦是现代免耕和转基因草甘膦抗性作物系统中高度依赖的除草剂。现在，该物种对草甘膦的抗性在美国非常普遍，并于2015年在巴西被发现。这一点已通过使用遗传标记进行物种鉴定，剂量反应研究、,草酸积累测定和EPSPS拷贝数测定得到了证实。巴西人对ALS基因（W574L和S653 N）的靶位点突变的两个不同等位基因所赋予的磺酰脲类和咪唑啉酮ALS抑制剂除草剂也具有抗性。通过分析系统地理学和多样性的模式，研究了美国不同地理区域八种不同草甘膦抗性（GR）和易感性（GS）棕榈棕榈种群之间的遗传相关程度，以确定抗性是独立发生还是从外部传播到亚利桑那州（AZ-R）。 Shikimate积累和EPSPS基因组拷贝测定证实了耐药性或敏感性。通过序列分型（GBS），UPGMA系统发育分析，主成分分析，基于贝叶斯模型的聚类以及成对比较遗传距离，发现了一组1351个单核苷酸多态性（SNP）。田纳西州的GR种群与佐治亚州和亚利桑那州的两个GS种群在遗传上是不同的，而堪萨斯州，亚利桑那州和内布拉斯加州的其余GS种群与亚利桑那州和乔治亚州的两个GR种群聚在一起。在后一组中，AZ-R与来自堪萨斯州和亚利桑那州的GS人群关系最密切，其次是来自佐治亚州的GR人群。来自佐治亚州和田纳西州的遗传资源种群在遗传上彼此不同。数据表明存在以下两种可能的情况：草甘膦抗性从东部引入亚利桑那州，或在亚利桑那州独立发展。佐治亚州和田纳西州的草甘膦抗药性很可能是分开发展的。因此，现代农民需要继续使杂草管理方法多样化，并防止种子散播，以减轻棕榈A.的除草剂抗性演变。

著录项

  • 作者

    Kuepper, Anita.;

  • 作者单位

    Colorado State University.;

  • 授予单位 Colorado State University.;
  • 学科 Plant sciences.
  • 学位 Ph.D.
  • 年度 2018
  • 页码 156 p.
  • 总页数 156
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号