What are the control methods for sweet potato weevil

The sweet potato weevil is also called the sweet potato ant-weevil; in Guangdong it is called shazi bug or shala bug, and it is one of the main pests harming sweet potatoes. In autumn sweet potatoes cultivated on dry sloping land, it occurs rather severely in the middle and late stages, with a general damage rate of 10%—15%, and in severely affected plots up to 40%—50%.

Control methods: where conditions permit, implement paddy-upland rotation, such as rice-sweet potato rotation, sweet potato-vegetable rotation, peanut-sweet potato rotation, sweet potato-corn rotation, etc., to eliminate insect sources in the field. In the middle and late stages of sweet potato growth, carry out hilling up several times, filling the cracks in the ridges to prevent the insects from invading through the cracks and causing damage. Strengthen water management, keep the ridge soil moist, and suppress the reproduction of this insect. Remove damaged tubers and burn them outside the field.

For chemical control, poisoned bait trapping and pesticide spraying can be used. Soak sweet potato slices in a 500-fold solution of 40% dimethoate emulsifiable concentrate or 90% crystalline trichlorfon for 12—20 hours, take them out and dry them, open a small hole in the sweet potato field, put the tuber poisoned bait into the hole, cover the surface with straw, place 50—60 small piles per mu of sweet potato field, and replace the poisoned bait once every 5—7 days to trap and kill adults. In the middle and late stages of autumn sweet potato growth, spray the sweet potato field with an 800—1000-fold solution of 90% crystalline trichlorfon, which can suppress the invasion and damage of this insect.