What are the harmful symptoms of corn borer? How to control corn borer?

Corn borer is a common pest, which mainly harms crops such as sorghum and corn, which hinders the growth of crops and aggravates the problems of yield and quality. Then how to prevent and cure it?

Living habits: this insect is the main pest in the middle and late growth stage of sorghum, but the damage is lighter than that of corn. There are 7 to 8 generations every year, and it takes 23 ~ 166 days for one generation. The egg stage is 3 ~ 8 days, the larval stage is 13 ~ 134 days, the prepupal stage is 1 ~ 2 days, and the pupal stage is 4 ~ 30 days. After 5th and 6th instar, the larvae pupated as thin cocoons in the damaged parts. However, after heading in sorghum, the larvae which could not decay into the stem due to tissue hardening would temporarily maintain their life at the rib base of the leaves, but could not pupate because of malnutrition. The adult is 12-15 mm long, light reddish brown to yellowish brown. The larva is 20-30 mm long and yellowish. There are many body tumors and bristles in each segment of the body.

Damage part and characteristics: adults lay eggs on the back of leaves. After hatching, the larvae endanger young leaves, male flowers and eat into stems, pedicels and ears, and many insect feces are excreted from wormholes. The parts above the boreholes of the killed plants dried up or were bent by the wind.

Prevention and control methods: before sorghum heading, when the heart leaf is found to be killed, spray organic phosphorus agents such as Pinus elliottii, or carbamate agents such as Baofu, etc.