Activity and field effect trials of lufenuron 50% EC against Spodoptera frugiperda.
The aim was to study control effect of 50 g/L lufenuron EC against Spodoptera frugiperda in maize. The toxic efficacy was observed by feeding method, and field trials were undertaken spraying method to evaluate the control effect of 50 g/L lufenuron EC against S. frugiperda in maize on different growth stages. The laboratory bioassay results showed that lufenuron had a high toxic activity, and the mortality rates were 80% and 98.33% on the 3rd and 4th day after treatment. The results of field test showed that the best application timing for 50 g/L lufenuron EC against S. frugiperda on maize plants at jointing stage, the next was ear period, the worst was granulation period. 7 days after spraying with 1:750 dilution ratio, the control effects were 93.07%, 64.24% and 43.21%, respectively. 50 g/L lufenuron EC could be used to control S. frugiperda, and the best control time was the bell stage and the effective concentration was 750 times.