Abstract: The resistant inheritance mode of Tetranychus cinnabarinus to fenpropathrin were studied based on the resistance selection in laboratory. After 40 generations selection, T. cinnabarinus developed 68.5-fold resistance to fenpropathrin. The methods of cross and back-cross between resistant (R) and sensitive (S) strains were used for exploring the inheritance mode of the resistance of this mite to fenpropathrin. The log (LC)-P equation of F1 got from obverse (SR) and reverse (RS) crosses was intermediate between S and R and inclined to S, the dominant indices DSR and DRS were - 0.83 and - 0.29, respectively, which indicated that the resistance is controlled by the incompletely recessive gene; the 95% confidence limit of this two dominant indices do not superpose showing DSR and DRS have significant difference and the maternal or external karyon effect may be existed in resistance inheritance; the back-cross results of heterozygote F1 with its parents suggested that the separation of progenies F2 (SR♀× S♂ and RS♀× R♂) was consistent with Mendel's single gene inheritance model.

Key words: Tetranychus cinnabarinus, Resistance, Fenpropathrin, Inheritance mode