Pest control of licorice

(1) leafhopper: there are mainly elm leafhopper, small green leafhopper and so on. It occurs in the whole growing period of licorice, and the damage is the most serious from late June to mid-August. When nymphs or adults suck the leaves, buds, young branches and buds of licorice, they first show silver spots, then the leaves lose green and show light yellow, and finally fall off.

Control method: remove the elm and other leafhopper overwintering hosts around the licorice field. The peak of the damage was prevented by spraying 2.5% deltamethrin 1000Mel 1500 times. Biological control was carried out with natural enemies such as aphids and ladybugs.

(2) short-haired weevil: a small green weevil that feeds on the roots of licorice. This insect has a long damage period and can be seen in licorice fields from May to September. The peak period of damage is from July to early August. It mainly feeds on the leaves, and the leaf margin is notched after feeding. Two to three generations occur every year, overwintering with adults or first-instar larvae in the cracks in the bark, licorice and weed roots.

Prevention and control methods: combine with weeding in autumn to destroy the overwintering place and reduce the overwintering base. Spray 2.5% deltamethrin 1000-5000 times, 45 kg per mu.

(3) Leaf beetle: Yulan leaf beetle and macular leaf beetle are the main leaf-eating pests of Glycyrrhiza uralensis in Hetao beach and lake silting land. Both adults and larvae feed on licorice leaves, and the leaves are riddled with holes; the residual leaves of killed licorice are yellow and shedding, which seriously affect photosynthesis and poor plant growth. The main damage period is from mid-July to late August. Two to three generations occur every year, with adults overwintering in weeds, under plant remains, in soil clods and soil seams.

Control methods: remove the residual branches and leaves in the field before overwintering, and kill the source of overwintering insects by irrigation and other methods. When the number of insects is large from May to June, 4.5% trichlorfon powder and 2.5% trichlorfon powder are used to control them, about 2.5 kg per mu. Spray 2.5% deltamethrin 2000-4000 times during the peak period.

(4) Glycyrrhiza seed wasp: the adults lay eggs on the seed coat in the green fruit stage. after hatching, the larvae eat the seeds and pupate within the species. After Eclosion, the adults break through the seed coat and escape, the damaged seeds are eaten-empty, and there are round holes in the seed coat and pods. This kind of insect has a great influence on seed yield.

Control methods: treat seeds, remove moth-eaten seeds or mix seeds with carbaryl powder. Spray 40% dimethoate EC 1000 times during the occurrence period, especially in the larval stage.

(5) Ningxia Carmine scale is a kind of piercing and sucking pest in the root of Glycyrrhiza uralensis. In addition to seriously harming wild licorice, artificial cultivated licorice in Inner Mongolia, Ningxia and Gansu have encountered destructive harm of this kind of pest.

The insect has a generation of one year and overwinters as newly hatched nymphs in the host rhizosphere. In its life history, only the adult stage lives briefly on the ground, and all other stages live underground. The main damage period is from early May to early August every year, and waxy spider-shaped red spheres can be seen on the rhizosphere of the host during the damage period.

Control methods: the best control period is the overwintering nymph finding host period from late March to early May and the adult mating and spawning period from early August to late August. In the early stage, internal inhalation insecticides can be used to open ditches for irrigation, and in the later stage, powder spraying and spray contact can be used.

In addition, there are mole cricket, he's oriental crab beetle in the emergence stage, and underground pests such as black wrinkle Gill beetle, yellow brown beetle, golden needle worm, pseudo-beetle and so on in the adult stage. In addition, licorice bean elephant, licorice diamondback moth and other hazards can be controlled by conventional pesticides, and attention should be paid to weeding before winter, eliminating the source of overwintering insects and removing the damaged plants in time.