Control of eggplant 28 star lady beetle

1. Morphological characteristics Adult yellow-brown, hemispherical. There are 6 black spots on the pronotum, 14 black spots of two sizes on each wing, and the black spots on the suture of the two wings are not connected. The eggs are bullet-shaped, yellow-white at the beginning of production and brown later. The eggs are densely arranged in the egg mass. Larvae when the first hatching is pale yellow, white, fusiform, multi-segment white branches thorn, branch thorn base has a dark brown ring. Pupa oval yellow white, black stripes on the back, the tail wrapped in the last instar larvae molt.

2. Living habits and occurrence rules

Coccinella octacospunctata occurs in Guangxi. It has 4~5 generations a year and overwinters as adults in weeds and soil crevices. It begins to reproduce in March every year, laying eggs on spring nightshade or other host plants. Eggs are mostly laid on the back of leaves, about 400 eggs per female. The newly hatched larvae cluster on the back of leaves first and disperse gradually after the third instar. The larvae are divided into 4 instars. The mature larvae hang upside down on the back of leaves to pupate. The generations of ladybug are overlapped, and many insect states exist in the same period. Adults in high temperature, strong light, often lurking in the back of the leaf, adults and larvae have photophobia and feigned death habits, a little vibration, that is, fall dead. In October, after harvesting, eggplant is transferred to suitable places for wintering.

3. control methods

(1) Artificial killing: using the habit of adult feign death, beating host plants in the morning and evening, catching and killing the fallen adults in a basin. The eggs are picked and destroyed during the peak laying period.

(2) Chemical control: Seize the opportunity of larva hatching or young larva stage to apply drugs at the right time. It can be sprayed with 20% fenvalerate or 2.5% deltamethrin 3000 times solution, or Mishashi 6000 times solution, or 50% phoxim EC 1000 times solution, or 2.5% kung fu EC 4000 times solution.