How to control the jujube bud weevil? Understanding its life habits is key

The jujube bud weevil belongs to the order Coleoptera, family Curculionidae. It occurs in Henan, Hebei, Shanxi, Liaoning and other famous jujube-producing areas, mainly harming jujube, apple, pear and other fruit trees.

The jujube bud weevil emerges from the soil in early spring and first damages the young buds of jujube trees. It is the earliest pest to appear on jujube trees. When the population density is high, it can eat all the jujube leaves, causing a second flush of buds and resulting in reduced yield or total crop failure.

The adult is dark gray or earth-yellow, with a black head, two curved elytra that are 2 times as long as wide, and a silvery-gray ventral surface. The eggs are milky white, turning brown later, oblong, and very small. The larvae are legless, milky white, and curved spindle-shaped.

This insect has 1 generation per year, overwintering as larvae in the soil at a depth of 5-10 cm. It pupates from March to April, and adults appear during the bud stage from April to June. The adults feed, first biting the larvae or young buds into notches and then eating them completely, causing a second flush of buds. Mid-April to early May is the peak period of adult damage.

The adults have a death-feigning habit. Eggs are laid in young buds, leaf axils and bark crevices. After hatching, the larvae move down along the trunk, enter the soil to live, and feed on plant roots. After September they enter the soil to overwinter. After the weather warms in spring, the larvae rise to a depth of 5-10 cm and make spherical earthen cells in which to pupate.

Control methods:

(1) Before the adults emerge from the soil, tie a 20 cm wide plastic film ring around the trunk, roll the upper part of the film downward, and tie a poisoned grass bundle in the middle of the film to prevent the jujube bud weevil from climbing the tree, eliminating it before it causes damage.

(2) Taking advantage of the adult's death-feigning habit, strike the jujube tree with a pole early in the morning to make the adults feign death and fall to the ground, then concentrate spraying to eliminate them.

(3) During the adult occurrence period, spray 2.5% phoxim 1500 times dilution to kill the adults that have climbed the tree.

(4) Spray 20% fenvalerate 5000 times dilution to control the adults.