Control efficiency and mechanism of spinetoram seed-pelleting against the striped flea beetle Phyllotreta striolata

The striped flea beetle (SFB, Phyllotreta striolata) can cause serious harm to cruciferous crops in both the larval and adult stages. Presently, there are no other sustainable alternatives to the use of chemical pesticides for controlling SFB infestation. In this study, the use of a seed-pelletized coating of spinetoram effectively reduced the numbers of SFB and its feedings on the flowering cabbage seedlings, whereas, in combination with the insect-proof net, it controlled the SFB infestation throughout the cabbage growth period. The analysis of the pesticide residues in soil and different cabbage parts indicated the degradation dynamics of spinetoram. The concentration of spinetoram in cabbage parts decreased over time, while increased first and subsequently decreased in soil. Furthermore, estimation of the half-life of spinetoram revealed that via seed-palletized application spinetoram half-life was found to be 2.82 days in soil, 4.21 days in the root, 5.77 days in the stem, and 3.57 days in the leaf, respectively. Both the lower pesticide residues and the half-life of spinetoram in soil and cabbage parts suggested it to be a promising environment and food-safe pesticide in controlling SFB. Moreover, the seed-pelletized coating ensured a sustainable release of spinetoram that can reduce the pesticide application frequency and be cost-effective and pocket-friendly for the farmers.