Toxicity of insecticides for the diamondback moth Plutella xylostella in the northwestern region of Russia
Keywords:
organophosphates, pyrethroids, carbamates, oxadiazines, diamides, biological efficacy, multiple resistanceAbstract
Development of multiple resistance in local populations of the cabbage moth Plutella xylostella to insecticides from different chemical classes was revealed in Leningrad Region in 2023–2024. This led to a decrease in the biological efficacy of the most widely used lambda-cyhalothrin and deltamethrin formulations, as well as some mixed formulations containing lambda-cyhalothrin and alpha-cypermethrin on white cabbage in the Tosnensky and Pushkinsky districts. On both crops, an initial stage of resistance development in the cabbage moth has been detected to the organophosphate malathion, the oxadiazine indoxacarb, the diamides cyanotranilyprol and flubendiamide, and on white cabbage in the Tosnensky district, to the carbamate methomyl, which complicates the protection system. To prevent further development of this negative phenomenon, it is necessary to discontinue the use of both pyrethroids and corresponding combined preparations on cabbage and rapeseed. Insecticide rotation schemes for controlling the cabbage moth should be developed for a particular field exploiting chemicals from new chemical classesб accompanied with regular monitoring of pest sensitivity in order to promptly exclude preparations which lose their efficacy.
