Abstract:

In order to further explore the safety of spinosyn in maize, the control effect, duration, field usage and dosage on Spodoptera frugiperda, and to screen out effective, safe and environmentally friendly agents for controlling Spodoptera frugiperda, Spinosyn 20% SC 150 mL/hm², 225 mL/hm², 300 mL/hm², emamectin benzoate 5% ME 300 mL/hm², indoxacarb 15% SC 225 mL/hm², chlorantraniliprole 200 g/L SC 225 mL/hm², were used to carry out the field plot efficacy test. The result showed that spinosyn 20% SC was safe to maize and had a good control effect on Spodoptera frugiperda. With the increase of the dosage per hectare, the control effect and duration increased. The control effect of spinosad 225 g / hm2 and 300 g / hm2 was more prominent, and the control effect was more than 90 % after 1-3 days of the first and second times, the control effect was above 75% after 14 days, and the seedling protection effect was still above 80% after 14 days. In addition, 21 days after the second dose, the control effect was still over 70%, and the seedling protection effect was more than 60%. The harm index of Spodoptera frugiperda to corn under the two treatments was 13.18-14.30, the harm level was controlled within level 2, and the damage degree of corn occurred lightly. It is recommended to use spinosyn 20% SC for controlling Spodoptera frugiperda of maize, with the dosage of 225 mL/hm². In the corn seedling stage, it can be sprayed once, and in the corn trumpet stage, it can be used to mix sand and spread it once.

Key words: maize, Spodoptera frugiperda, spinosyn, field efficacy