Abstract
Fipronil bait (0.5% active ingredient, Prince®, BASF Agro) is a recently introduced insecticide for wireworms. We examined its effects on the growth and yield of sugarcane during spring cropping and ratoon cropping, on Kume Island, Okinawa, Japan. During spring cropping, fipronil bait significantly lowered the number of dead heart stalks in comparison with a more conventional insecticide against wireworms, ethylthiodemeton granules (3.0% active ingredient, TD®, Sankyou Agro). The number of damaged buds and the damage rate were significantly lower, and the number of stalks and the sugarcane yield were significantly higher in fipronil-baited areas than in untreated areas. During ratoon cropping, however, these effects were not detected, and insect damage reappeared. We conclude that fipronil bait treatment during planting increases sugarcane yield but, following ratoon cropping, it is necessary to re-treat with fipronil bait or other insecticides to prevent a recurrence of insect damage.
