Myzus persicae

(scientific name of pest) Myzuspersicae (Sulzer)

Peach aphids are polyphagous pests, which can harm radish, cabbage, rape, mustard, turnip, eggplant, pepper, tomato, melon, legume, spinach and so on in vegetables, and peach, plum, apricot and cherry in fruit trees.

(pest identification) adult aphids and nymphs cluster on the back of the leaves to suck sap, causing the damaged leaves to turn yellow and atrophy. If the group gathers in the tender stem and pedicel of the seed vegetable, the pedicel will be distorted. Peach aphids can also spread viral diseases. Peach aphids belong to Homoptera and Aphididae. The wingless parthenogenetic aphid is about 2.6 mm long, the body is green, yellowish green or fuchsia, the frontal tumor is well developed and tilts inward. The ventral canal is longer, longer than the fifth segment of the antennae, darker at the end, dilated in the middle and posterior, and constricted at the end. Tail conical, with 3 pairs of hairs on both sides. The winged parthenogenetic aphid is about 2 mm long, the head is black, and the frontal tumor is prominent, tilting inward. Compound eyes are reddish brown. Black chest, green and yellowish green abdomen, light black markings on the back. The ventral canal and tail are the same as the wingless female aphid.

Peach aphids occur everywhere, ranging from 10 to 40 generations a year. There are more than 10 generations a year in the north, 2428 generations in Shandong, Anhui and other places, 30 generations in Hunan and 40 generations in Guangdong. In winter in the north, most peach aphids winter with fertilized eggs in the branches or buds of peach trees, and some of them winter with autumn vegetables in the vegetable cellar or in winter vegetables, and can reproduce all the year round in greenhouse and other protected areas; in the south, because of the high temperature, they can reproduce all the year round on cruciferous vegetables without overwintering. From March to April of the following year, the overwintering eggs began to hatch. After breeding on the overwintering host for several generations, the winged aphid migrated to the vegetable field, first propagated on cruciferous vegetables, then spread to Solanaceae vegetables, legumes and other crops, and then moved to the overwintering host in mid-and late October to overwintering. Aphids overwintering with parthenogenetic aphids in autumn vegetables or in winter vegetable fields can be directly transferred to vegetable fields in early spring, and this part occurs early; in protected areas, especially in greenhouses, they can reproduce throughout the year. Peach aphids have short generations, strong fecundity and serious generation overlap. Peach aphids have a strong tendency to yellow and orange, followed by green and negative to silver gray. Yellow sticky plates or yellow dishes can be used to trap or predict the growth and decline of aphids, and silver gray film can be used to avoid aphids to prevent aphids from spreading virus diseases. The optimum temperature for the development of peach aphid is about 24 ℃, and the relative humidity is 50% and 80%. In addition, the occurrence of natural enemies of peach aphids has a great influence, such as ladybugs, lacewings, aphid flies, aphid cocoon wasps, etc., if the number of natural enemies is large, aphids can be controlled.

(control measures) (1) making use of the aphid's tendency to yellow, setting up yellow sticky board in the field can attract a large number of winged aphids, and the control effect is more significant in the protected field. (2) Pesticide control. 50% aldicarb wettable powder 2000 × 3000 times, or 40% or 50% dimethoate EC 1000 times 1500 times, or 2.5% deltamethrin EC 3000 times, or 2.5% kungfu EC 3000 times, or 25% cypermethrin EC 1500 times, or 20% chrysanthemum EC 2000 times, or 10% dichlorvos cyanide EC 4000 times spray.