Insecticide Resistance and the Genotype Frequencies of Genes in the Diamondback Moth (Plulella xylostella L.) from Different Populations

The resistance of the diamondback moth (DBM) to bissultap, dichlorvos, malathion and abamectin was tested using the typical method of FAO. DBMs from Beijing, Guangzhou, Japan as well as strain from Taiwan were sampled. The results showed that the DBMs collected from Japan, Guangzhou are very strongly resistant to dichlorvos. The resistant rates of abamectin to Japan and Guangzhou populations are 4.85 and 11.29 times respectively. The highest resistant genotype frequencies are formed in Guangzhou, Dongwan, and Beijing DBM populations, with the resistant genotype frequencies of 41.25%, 41.25% and 58.23% respectively. A quick method of determining insecticide resistance genotype frequencies was verified, and the tactics of integrated managements according to the insecticide resistance genotype frequencies of the DBMs in different populations was discussed.