Pear crown reticule bug is also known as pear reticulate bug, pear army worm, or ma beef cattle. It is mainly harmful to cherries, plums, pears, apples, begonias, hawthorns, poplars, moon seasons and so on.
First, the morphological characteristics of pear crown reticulated bugs
1. Adult insects. The body is 3.5 mm long, flattened, black-brown, and the forewings are densely reticulated. The head is reddish brown with 5 yellow-white head spines on the head and light yellowish brown antennae.
2. Eggs. Oblong oval. It is pale green at the beginning of labor, and later becomes yellowish and transparent.
3. Nymphs. The first instar insects are milky white and nearly transparent, and later turn light green to dark brown. Old nymphs have spikes on the head, thorax, and abdomen.
Second, pear crown reticulum bugs are harmful symptoms
Adults and nymphs suck sap on the back of the leaf, and the excreted feces and the black spots left during egg laying make the back of the leaf rusty yellow, and many white spots appear on the front of the leaf, which seriously affect photosynthesis. When it occurs in large numbers, it can cause early leaf shedding, affecting tree posture and flower bud formation.
Third, the occurrence of pear crown reticulum bugs
It occurs in 4 generations per year, and adult insects overwinter under leaves, weeds, and in soil crevices and branches. In early April, the overwintering adults begin to infest the trees and lay eggs to reproduce. After mid-May, the first generation of eggs hatches, and the hatching larvae are poorly active and sensitive to agents, which is a critical period for spray control. Later, various insect forms appeared, and there was a generational overlap. July and August are the main occurrence periods throughout the year, and after mid-to-late October, they gradually enter the wintering places.
Fourth, pear crown net bug control methods
1. Agricultural prevention and control. After the cherry leaves, thoroughly clean up the dead branches and weeds in and around the orchard, scrape off the warped skin, burn it centrally or bury it deeply, and turn over the tree tray to eliminate the overwintering adult insects after removal.
2. Chemical control. In the pear reticule bug occurrence period after cherry harvesting, when the overwintering adults emerge from the tree, the first generation of nymphs all hatch, and the first generation of adults only appear individually when sprayed for control. Spray the tree with 1.8% avermectin emulsion 4000 times liquid, or 5% high-efficiency cypermethrin emulsion 2000 times liquid, or 10% imidacloprid wettable powder 4000 to 5000 times liquid, or 2.5% flutter aphid wettable powder 2000 times liquid. Focus on spraying the back of the leaf blade.