Jalaludin Adam, Yu Qin, Zoellner Peter, Beffa Roland, Powles Stephen B
Australian Herbicide Resistance Initiative, School of Plant Biology, University of Western Australia, WA, Australia.
Research Technologies Bayer AG, Industriepark Hoechst, Frankfurt, Germany.
Pest Manag Sci. 2017 Jun;73(6):1091-1100. doi: 10.1002/ps.4528. Epub 2017 Feb 20.
An Eleusine indica population has evolved resistance to glufosinate, a major post-emergence herbicide of global agriculture. This population was analysed for target-site (glutamine synthetase) and non-target-site (glufosinate uptake, translocation and metabolism) resistance mechanisms.
Glutamine synthetase (GS) activity extracted from susceptible (S) and resistant (R*) plants was equally sensitive to glufosinate inhibition, with IC values of 0.85 mm and 0.99 mm, respectively. The extractable GS activity was also similar in S and R* samples. Foliar uptake of [ C]-glufosinate did not differ in S and R* plants, nor did glufosinate net uptake in leaf discs. Translocation of [ C]-glufosinate into untreated shoots and roots was also similar in both populations, with 44% to 47% of the herbicide translocated out from the treated leaf 24 h after treatment. The HPLC and LC-MS analysis of glufosinate metabolism revealed no major metabolites in S or R* leaf tissue.
Glufosinate resistance in this resistant population is not due to an insensitive GS, or increased activity, or altered glufosinate uptake and translocation, or enhanced glufosinate metabolism. Thus, target-site resistance is likely excluded and the exact resistance mechanism(s) remain to be determined. © 2017 Society of Chemical Industry.
牛筋草种群已对草铵膦产生抗性，草铵膦是全球农业中一种主要的苗后除草剂。对该种群进行了靶标位点（谷氨酰胺合成酶）和非靶标位点（草铵膦吸收、转运和代谢）抗性机制分析。
从敏感（S）和抗性（R*）植株中提取的谷氨酰胺合成酶（GS）活性对草铵膦抑制同样敏感，IC值分别为0.85 mM和0.99 mM。S和R样品中可提取的GS活性也相似。[14C]-草铵膦的叶面吸收在S和R植株中无差异，叶圆片中草铵膦的净吸收也无差异。[14C]-草铵膦向未处理的地上部和根部的转运在两个种群中也相似，处理后24小时，44%至47%的除草剂从处理叶片中转运出去。草铵膦代谢的HPLC和LC-MS分析表明，S或R*叶组织中没有主要代谢物。
该抗性种群对草铵膦的抗性不是由于GS不敏感、活性增加、草铵膦吸收和转运改变或草铵膦代谢增强。因此，可能排除了靶标位点抗性，确切的抗性机制仍有待确定。© 2017化学工业协会。
