Kleinman Ziv, Rubin Baruch
Robert H Smith Institute of Plant Sciences and Genetics in Agriculture, Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Rehovot, Israel.
Pest Manag Sci. 2017 Jan;73(1):246-253. doi: 10.1002/ps.4293. Epub 2016 May 20.
Conyza spp. were the first broadleaf weeds reported to have evolved glyphosate resistance. Several mechanisms have been proposed for glyphosate resistance. In an effort to elucidate the mechanism of this resistance in Conyza bonariensis, possible target-site and non-target-site mechanisms were investigated in glyphosate-resistant (GR) C. bonariensis biotypes.
Using differential glyphosate applications and analyses of shikimate accumulation, we followed the herbicide effect in different plant organs and monitored the herbicide's apparent mobility. We found high shikimate levels in the roots and young leaves of glyphosate-sensitive (GS) plants, regardless of the site of application, whereas in GR plants, shikimate accumulated mainly in treated young leaves. C-glyphosate studies, however, revealed the expected source-to-sink translocation pattern in both GS and GR plants. Sequencing of the appropriate EPSPS DNA fragments of GR and GS plants revealed no alteration at the Pro106 position.
These data support the hypothesis that the glyphosate resistance of our C. bonariensis GR biotypes is associated with altered subcellular distribution of glyphosate, which keeps the herbicide sequestered away from the EPSPS target site in the chloroplast. © 2016 Society of Chemical Industry.
白酒草属植物是最早被报道对草甘膦产生抗性的阔叶杂草。针对草甘膦抗性已提出了多种机制。为了阐明阿根廷白酒草对草甘膦的抗性机制，对草甘膦抗性（GR）阿根廷白酒草生物型的可能靶标位点和非靶标位点机制进行了研究。
通过不同的草甘膦施用方式和莽草酸积累分析，我们跟踪了除草剂在不同植物器官中的作用效果，并监测了除草剂的表观移动性。我们发现，无论施药部位如何，草甘膦敏感（GS）植物的根和幼叶中莽草酸水平都很高，而在GR植物中，莽草酸主要积累在处理过的幼叶中。然而，C-草甘膦研究揭示了GS和GR植物中预期的源到库的转运模式。对GR和GS植物的适当EPSPS DNA片段进行测序，发现在第106位脯氨酸处没有改变。
这些数据支持这样的假设，即我们的GR阿根廷白酒草生物型对草甘膦的抗性与草甘膦亚细胞分布的改变有关，这种改变使除草剂与叶绿体中的EPSPS靶标位点隔离。©2016化学工业协会。
