What are the control measures for aphids in peach tree cultivation?

There are many species of aphids; the main ones harming peach trees are three: the green peach aphid, the peach powder aphid, and the peach tuber aphid.

(1) Damage characteristics.

All three aphids, when the peach tree sprouts and unfolds its leaves, gather as adults and nymphs on the underside of peach leaves and on tender shoots, sucking sap and damaging the leaves. The damaged leaves show small black, red, or yellow spots, causing the leaves to gradually turn white and curl; in severe cases this causes defoliation, weakens the tree vigor, and affects the yield and flower bud formation of the peach tree. Therefore, timely control must be carried out.

(2) Control methods. The best time to control aphids is when the leaf buds of the peach tree show green and the flower buds appear; at this time, apply pesticide once, and afterwards apply 1 to 2 more times according to the pest situation. Each application must be made before leaf curling occurs, otherwise the control effect will be affected. The specific methods are:

① Spraying pesticides. There are many pesticides that can be selected; those commonly used in production include: 35% endosulfan emulsifiable concentrate 1500 times dilution; 50% pirimicarb 3000-4000 times dilution; 50% phoxim emulsifiable concentrate 1500 times dilution; 40% omethoate 1500 times dilution; 50% malathion (Marathon) emulsifiable concentrate 1000 times dilution; 10% imidacloprid (pifuxiya) wettable powder 5000 times dilution, etc. To improve the control effect, a certain amount of spreader can be added to the pesticide solution; several pesticides should be used alternately, and the use of a single pesticide should be avoided as much as possible.

② Trunk smearing with pesticide. Take 1 part of 40% omethoate, add 1 part of multifunctional plant synergist, add 2 parts water, and mix into a pesticide solution. Use a brush to apply a pesticide ring about 10 cm wide on the trunk. If the bark is rough, first scrape off the old peeling bark before applying the pesticide. After application, wrap it well with newspaper or plastic film.

③ Trunk injection. That is, use an iron awl to pierce holes diagonally from top to bottom on the main trunk, reaching deep into the xylem, then use a No. 8 syringe to inject 40% dimethoate, and seal the hole opening; after 2-3 days, more than 95% of the aphids can be killed.

④ Protect natural enemies. There are many natural enemies of aphids, such as ladybugs, hoverflies, lacewings, parasitic wasps, etc., all of which have a strong suppressing effect on aphids. Therefore, spray broad-spectrum insecticides as little as possible and avoid spraying during periods when natural enemies are abundant, so as to protect natural enemies and use them to eliminate aphids. This is of great significance for protecting the orchard ecological environment and producing pollution-free green fruit.