Malone Jenna M, Morran Sarah, Shirley Neil, Boutsalis Peter, Preston Christopher
School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, SA, Australia.
Department of Plant Sciences, University of California Davis, Davis, CA, USA.
Pest Manag Sci. 2016 Jan;72(1):81-8. doi: 10.1002/ps.4019. Epub 2015 May 6.
Glyphosate is the most widely used herbicide in the world and has been intensively used to control B. diandrus, a problematic weed of crops and pastures in southern Australia.
Resistance to glyphosate was identified in two populations of B. diandrus that were nearly fivefold more resistant to glyphosate than wild-type plants. Both populations contained EPSPS gene amplification, with resistant plants having an average of around 20-fold the number of copies of EPSPS compared with susceptible plants. EPSPS expression was also increased in resistant plants of both populations; however, expression levels were not correlated with the number of EPSPS copies. Amplification of only one of the four EPSPS genes present in B. diandus was detected. Investigation into the inheritance of glyphosate resistance found no segregation in the F2 generation. Every individual in the F2 populations contained between three and 30 copies of EPSPS; however, on average they contained fewer copies compared with the parent resistant population.
Glyphosate resistance in B. diandrus is due to EPSPS gene amplification. Resistance is heritable but complex.
草甘膦是世界上使用最广泛的除草剂，已被大量用于防治澳大利亚南部农作物和牧场中的有害杂草——双穗雀稗。
在两个双穗雀稗种群中鉴定出了对草甘膦的抗性，这些种群对草甘膦的抗性比野生型植物高近五倍。两个种群均存在5-烯醇丙酮酰莽草酸-3-磷酸合成酶（EPSPS）基因扩增，与敏感植物相比，抗性植物的EPSPS拷贝数平均约为其20倍。两个种群的抗性植物中EPSPS的表达也有所增加；然而，表达水平与EPSPS拷贝数无关。在双穗雀稗中存在的四个EPSPS基因中，仅检测到其中一个基因的扩增。对草甘膦抗性遗传的研究发现，在F2代中没有分离现象。F2种群中的每个个体含有3至30个EPSPS拷贝；然而，与亲本抗性种群相比，它们平均含有的拷贝数较少。
双穗雀稗对草甘膦的抗性是由于EPSPS基因扩增。抗性是可遗传的，但较为复杂。
