Harm and control of aphids

Aphids are a kind of herbivorous insects, also known as greasy insects, honey insects, etc., including all members of Aphididae, which are widely distributed all over the world, but they are mainly concentrated in temperate regions. at present, there are about 4400 species of aphids in 10 families, of which about 4400 species are seriously harmful to agroforestry and horticulture.

The harm of aphids

Most species of aphids are oligophagous or monophagous, a few are polyphagous, and some of them are important pests of economic plants such as grain, cotton, oil, hemp, tea, sugar, vegetables, tobacco, fruit, medicine and trees. Due to the repeated transfer and taste of host plants during migration and spread, many plant virus diseases can be transmitted and cause more harm, including wheat aphid, wheat aphid, cotton aphid, peach aphid and radish aphid and other important pests.

The habits of aphids

Aphids have a pair of ventral tubes, which are used to expel defense fluids that can harden rapidly, and the composition is triglycerides. The ventral tubes are usually tubular, often longer than wide, and the base is thick, sucking plant juices, so they are major plant pests, which not only hinder plant growth, form galls and spread viruses, but also cause deformities of flowers, leaves and buds. The life cycle of the wingless female is complex. In summer, the wingless female parthenogenetic, oviparous, and produces young aphids. When the aphids on the plant are too dense, some grow two pairs of large membranous wings to look for a new host. Female aphids and male aphids appear at the end of summer. after mating, female aphids lay eggs and use eggs to survive the winter.

Control of aphids

1. Protect natural enemies: there are many natural enemies of aphids, such as ladybugs, aphid-eating flies, parasitic wasps, aphid-eating gall mosquitoes, crab spiders, lacewings and entomopathogenic fungi. These natural enemies have a strong inhibitory effect on aphids. Therefore, broad-spectrum pesticides can be applied as little as possible, at the same time, the application of pesticides during the peak period of natural enemy activity can be avoided, and aphids can be artificially reared and released under certain conditions.

2. Artificial control: brush white at the base of the trunk in autumn and winter to prevent aphids from spawning. Cut off the damaged branches and residual flowers and burn them centrally to reduce the overwintering insect population. Scrape or brush off the dense overwintering eggs on the bark in winter, clean up the residual branches and leaves in time, and reduce the overwintering eggs. When a small amount of aphids are found on flowers in spring, brush can be dipped in water.

3. Drug control: spraying pesticides in time when a large number of aphids are found, spraying plants twice with 50% marathon emulsion 1000 times, or 50% fenitrothion emulsion 1000 times, or 50% aldicarb wettable powder 3000 times, or 2.5% deltamethrin emulsion 3000 times, or 2.5% methomyl emulsion 3000 times, or 40% imidacloprid water solvent 1500 times 2000 times, etc.