Evaluation on pest control effect of seed pelletized coating brewed sorghum

To evaluate the control effect of seed pelletized coating of insecticide on main pests, the contents of chlorantraniliprole and thiamethoxam in the leaves of plants, the changes of chemical composition as well as the control effect of main pests (borer and Melanaphis sacchari) during different growth stages of brewed sorghum under seed pelltized coating and conventional seed coating treanments through the laboratory test and field experiment were compared. The results showed that the concentration of pesticide content in leaves of seed pelletized coating of insecticide treatment, which was lower than that of conventional seed coating treatment during prometaphase of brewed sorghum growth. The contents of soluble sugar and flavonoid contents of seed pelletized coating treatment were significantly higher than those of conventional seed coating treatment at each stages; at booting stage, the control effects of seed pelletized coating on borer moth and Melanaphis sacchari were 95.89% and 85.40% respectively, and there was no significant difference when compared with that of the conventional chemical control treatment (P > 0.05); the synergistic participation of residual pesticides and secondary metabolites in leaves were the main reason for the long-term control of target pests by seed pelletized coating treatment. Therefore, seed pelletized coating of insecticide could bring long-term control over main pests, and could reducing pesticide use by 1~2 applications or enabling chemical-free cultivation, during the early and middle growth stages of brewed sorghum. This study will provide new insight for pest control and field cultivation management in the production of brewed sorghum.