Control methods of tea caterpillar

Tea caterpillar is an important pest in Chinese tea area. it is an insect of the genus Lepidoptera, which is also known as tea yellow moth, swinging head worm and so on. Tea caterpillar is distributed in all tea-producing provinces in China, mainly harming tea, camellia, citrus, etc., and tea leaves run out of food when it is serious. Let's take a look at the control methods of tea caterpillar.

Morphological characteristics of Dendrolimus punctatus

The adult body is about 6mm long and the wingspan is about 20mm. The female moth is slightly larger and has yellowish brown wings. Xiong E is slightly smaller and brown. There are two yellowish stripes in the middle of the forewing and two black spots in the yellowish area of the wingtip. There are yellow hair clusters at the end of the female moth. The eggs are laid in blocks, the egg blocks are oval and covered with yellow hairs. The mature larva is about 20 mm long and yellowish brown. The three segments of the chest are a little smaller. There are 8 yellow (Prophase) or black hairy tumors in each segment, with yellow-brown poisonous hairs on them. All are also densely covered with yellow poisonous hairs of uneven length. The pupa is yellowish brown, about 9 mm long, with a thin khaki silk cocoon, which is about 12-14 mm long.

Occurrence regularity of tea caterpillar

The occurrence algebra of tea caterpillar is different in different places. It occurs three generations a year in Hunan, overwintering with eggs on the back of old leaves, and the harmful periods of each generation of larvae are from April to May, June to July and August to October respectively, and generally occur heavily in spring and autumn. After maturing, the larvae formed cocoons and pupated under the surface of deciduous soil in the rhizosphere of tea bushes. The female moth lays eggs on the back of the old leaves. The larvae were 6-7 instar, clustered and strongly clustered before the 3rd instar. Tens to hundreds of larvae often gathered on the back of the leaves to feed on the lower epidermis and mesophyll, leaving the upper epidermis in the shape of a translucent yellowish green film. After 3 years old, it began to disperse into groups and became harmful, and the bite of the leaves showed a lack of engraving. The larvae mature and pupate under the litter in the rhizosphere of tea bushes or in shallow soil. Adults have phototaxis.

Control methods of tea caterpillar

1. Manual capture: from November to April of the following year, the overwintering eggs are removed, the parasitic peaks are protected, and the larvae are killed.

2. kill pupae at the right time: combine with ploughing and cultivating soil to kill pupae at the right time.

3. Trapping and killing adults: lighting lights to trap moths, sexual inducement.

4. Chemical control: preferably before the 3rd instar of the larvae, 90% crystal trichlorfon or 50% marathon emulsion, 25% imidophos emulsion, 50% fenitrothion 1000-3000 times, or 80% dichlorvos 2000-3000 times, soap water 150 times.

5. Biological control: spraying green worm fungus powder (containing 15 billion spores per gram) 500x liquid.