截形叶螨对阿维菌素的抗性遗传方式研究

Study on the inheritance of resistance of Tetranychus truncatus Ehara to abamectin

采用室内盆栽试验研究了截形叶螨(Tetranychus truncates Ehara)抗性品系(RR)对杀菌剂阿维菌素的遗传方式。结果表明,截形叶螨抗性种群的杂交F1代(SS♀×RR♂和RR♀×SS♂)的显性度D值分别为0.479和0.636,均在0 <D<1范围内,表明抗性由不完全显性基因控制;两个D值(DSR和DRS)95%置信限有重叠,并且经t检验,两个D值不存在显著差异(P>0.05),证明截形叶螨对阿维菌素的抗性遗传受母体或核外效应的影响不大,其抗性基因在常染色体上;回交F2代两个种群的(BC1SR和BC1RS)的实际死亡率和期望值经χ2检验,均差异显著,证实由多基因控制。

Cross and backcross between the resistant strain(RR) and the susceptible strain(SS) of Tetranychus truncatus Ehara were carried out to explore the inheritance of resistance of T. truncatus Ehara to abamectin. The Results showed that the D for the F1 females from SS♀×RR♂ crosses and RR♀×SS♂ crosses were 0.479 and 0.636, respectively, which were in the range of 0 < D < 1, illustrating an incompletely dominant inheritance feature. The 95 % confidence limit of the two degrees of dominance superposed, showing no significant difference between DSRand DRS. It revealed that the resistance gene was located in the autosome. The chi-square(X^2) goodness-of-fit analysis indicated that mortalities observed in F2 females(BC1 SRand BC1 RS) were significantly different(X^2= 16.92, df=9, P<0.05) from expected values for multiple genes control. Consequently, abamectin should be used in rotation with the other insecticides to reduce selection pressure, and it is very important to take out and implement preventive resistance management strategy and measures.