Kaundun Shiv Shankhar, Jackson Lucy Victoria, Hutchings Sarah-Jane, Galloway Jonathan, Marchegiani Elisabetta, Howell Anushka, Carlin Ryan, Mcindoe Eddie, Tuesca Daniel, Moreno Raul
Herbicide Bioscience, Syngenta Ltd, Jealott's Hill International Research Centre, Bracknell, RG42 6EY, UK.
Syngenta, Research Triangle Park, NC 27709, USA.
Plants (Basel). 2019 Nov 16;8(11):512. doi: 10.3390/plants8110512.
The mechanism and expression of resistance to glyphosate at different plant growing temperatures was investigated in an population (VM1) from a soybean field in Vicuña Mackenna, Cordoba, Argentina. Resistance was not due to reduced glyphosate translocation to the meristem or to duplication, as reported for most US samples. In contrast, a proline 106 to serine target-site mutation acting additively with over-expression (1.8-fold increase) was respectively a major and minor contributor to glyphosate resistance in VM1. Resistance indices based on LD values generated using progenies from a cross between 52 PS106 VM1 individuals were estimated at 7.1 for homozygous SS106 and 4.3 for heterozygous PS106 compared with homozygous wild PP106 plants grown at a medium temperature of 24 °C day/18 °C night. A larger proportion of wild and mutant progenies survived a single commonly employed glyphosate rate when maintained at 30 °C day/26 °C night compared with 20 °C day/16 night in a subsequent experiment. Interestingly, the P106S mutation was not identified in any of the 920 plants analysed from 115 US populations, thereby potentially reflecting the difference in control practices in Argentina and USA.
在来自阿根廷科尔多瓦省维库尼亚·麦肯纳市一块大豆田的一个种群（VM1）中，研究了不同植物生长温度下对草甘膦抗性的机制和表达情况。抗性并非像大多数美国样本所报道的那样，是由于草甘膦向分生组织的转运减少或基因重复所致。相反，脯氨酸106突变为丝氨酸的靶位点突变与过表达（增加1.8倍）相加作用，分别是VM1中草甘膦抗性的主要和次要贡献因素。基于使用52个PS106 VM1个体杂交后代产生的致死剂量（LD）值计算的抗性指数，与在24℃日/18℃夜的中等温度下生长的纯合野生型PP106植株相比，纯合SS106的抗性指数估计为7.1，杂合PS106的抗性指数为4.3。在随后的实验中，与20℃日/16℃夜相比，当维持在30℃日/26℃夜时，更大比例的野生型和突变型后代在单一常用草甘膦剂量下存活。有趣的是，在从115个美国种群分析的920株植物中，未发现任何一株存在P106S突变，这可能反映了阿根廷和美国在防治措施上的差异。
