湖南省部分地区棉田牛筋草(Eleusine indica)对精喹禾灵的抗性

采用整株法测定了湖南省部分地区棉田牛筋草(Eleusine indica)对精喹禾灵的抗性水平,还测定了精喹禾灵对牛筋草抗(R)、感(S)种群体内GSTs及SOD、POD、CAT影响的差异。整株法测定结果显示,相对于敏感的南县种群,其他地区棉田牛筋草对精喹禾灵的抗性指数在1.6~9.7之间,其中湘阴种群最高为9.7,澧县种群最低为1.6;精喹禾灵处理2d后,R种群GSTs活性急剧上升,在第3天达到最高,随后急剧下降,5d之后趋于平缓。S种群GSTs活性在施药后先上升后下降。药剂处理后,R种群的SOD和POD活性在中期显著低于S种群,R、S种群的CAT活性在药后第9天有明显差异。结果表明,R种群对精喹禾灵产生抗性的原因可能是GSTs对精喹禾灵的代谢作用加强,抗氧化酶系活性的变化可能与抗性相关。

Resistance of Eleusine indica to quizalofop-P-ethyl in some cotton fields in Hunan Province

In order to evaluate the resistance of Eleusine indica populations to quizalofop-P-ethyl, whole-plant bioassay was carried out and the differences in GSTs, SOD, POD and CAT of the resistant (R) and susceptible (S) populations to quizalofop-P-ethyl were preliminarily compared. The results of whole-plant bioassay showed that the populations of E.indica had different levels of resistance to quizalofop-P-ethyl, and the highest resistance index (RI) was 9.7, which was found in Xiangyin County. The activity of R population increased immediately, with a peak value of 2.6 times of the control, while the S population increased at first and then declined, with a peak value of 2.2 times. The SOD and POD activities of R population were significantly lower than that of S population in the medium term. The CAT activity of R population was significantly higher than that of S population after 9 days. The results indicated that the increased metabolic activity may be one of the resistance mechanisms to quizalofop-P-ethyl in E. indica. Oxidative stress may be related to the mode of action of quizalofop-P-ethyl.