截形叶螨抗哒螨灵种群抗性遗传方式的研究

Resistance inheritance patterns to pyridaben in Tetranychus truncatus

通过对室内选育出的截形叶螨敏感品系和抗哒螨灵品系的杂交和回交试验表明:所测得的截形叶螨正交F1SR(SS♀×RR♂)和反交F1RS(RR♀×SS♂)代的显性度DSR和DRS分别为0.40和0.60,表明抗性由不完全显性基因控制;两个D值(DRS和DSR)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),证明截形叶螨对哒螨灵的抗性遗传为常染色体控制;回交F2代(BC1RS和BC1SR)的实际死亡率和期望值经χ2检验,无显著性差异(χ2=9.72,df=9,P>0.05),表明抗性遗传由单基因控制。

Cross and backcross between the pyridaben-resistant strain （Py-R）and susceptible strain （SS） were used to ex- plore the inheritance pattern of Tetranychus truncatus Ehara to pyridaben. The estimated degrees of dominance （D） for the F1 females from SS♀- XRR♂ crosses and RR♀- XSS♂ crosses were 0.40 and 0.60, reslZectively, illustrating an in- completely dominant inheritance of resistance. The 95% confidence limit of the two degrees of dominance was super- posed, showing no significant difference between Dsn and Din. It revealed that the resistance inheritance was not mater- nal inheritance. The chi- square （ Z2 ） goodness- of- fit analysis indicated that the mortalities observed in F2 females （F15R♀XSS♂ and MRs ♀- XRR♂ ） were not significantly different （x2 =9.72, df=9, P〉0. 05）from the expected values. It indicated that the resistance was consistent with single-gene inheritance model.