Cotton aphid, a pest of lily

The damage to plants is second only to peach aphids, and there are many host species, such as chrysanthemum, lilies and so on.

Morphological characteristics: female aphids are winged or wingless, the body is very small, initially yellowish, then black. Feet and antennae are yellow and white. The male aphids have no wings, which is 1 inch shorter than that of the female aphids, and the color is similar. The egg is oval, yellow at birth and black when hatching. The nymph is grayish white at the beginning, and then turns yellow. When mature, the winged aphids on the chest and back are winged female aphids and those without winged buds are wingless female aphids.

Harmful habits: cotton aphids can occur for 20 generations a year, overwintering with eggs in plant roots. The parthenogenetic parthenogenesis was carried out on the overwintering host in March of the following year, resulting in winged aphids and migrating to plants. The damage was serious in July and August and overwintered by mating and spawning in October. Cotton aphid harms young branches, leaves and buds, makes leaves green and curl, texture hardens and becomes brittle, and when serious, the whole plant wilts.

Prevention and control: eliminate the source of overwintering insects, remove nearby weeds, and thoroughly clear the garden and fields. Spray 40% dimethoate or omethoate 1200 times, or aphid pine emulsion 1200 times, or 2.5% rotenin 1000-1500 times during the aphid damage period. To protect natural enemies is to protect seven-star ladybugs, aphid flies and lacewings.