There are many types of aphids, but the main ones that harm peach trees are peach whiteflies and peach tumor aphids, and peach aphids can also be pests. All three species of aphids belong to the family Homoptera, also known as oil worms or honey worms. Aphids are stinging or mouthparts that often gather densely on the shoots and leaves to suck sap, weakening the tree and spreading the virus.
Peach tree aphids are mainly harmful symptoms
1. The leaf surface of the peach powder aphid leaf is rolled back to the longitudinal roll, into a spoon shape, and the leaves often have white wax powder secreted by aphids; and because of its secretion of honey, it often causes coal pollution disease, and the branches and leaves are black when it is serious.
2. The leaf of peach tumor aphid is longitudinally rolled from the edge to the back of the leaf, and the tissue at the curl is thick, uneven and uneven, the initial color is pale green, then it becomes red, and the whole leaf is curled in severe cases.
3. The peach aphid leaves turn yellow, irregularly curl and shrink the leaves, and finally dry and fall off.
Life habits of peach tree aphids
Peach tree aphids take the peach mealy aphid as an example: in winter, the eggs overwinter at the cracks in the bud armpits and bark of plum, peach, apricot and other fruit branches, and hatch when the buds germinate the following year, and continue to multiply in the form of wingless parthenogenesis. From June to August, winged aphids are produced and moved to the summer host (grass weeds), which do not harm fruit trees at this time; in late autumn, aphids move back to peach and other fruit trees. There are 10 to 30 generations a year, with more in the south and less in the north. The period of serious harm is from May to August. The developmental species of aphids are related to nitrogen fertilization, and the more nitrogen fertilizer is applied, the faster the aphids grow.
Peach tree aphid control party
1, the use of natural enemies to control in the aphid pest does not reach the economic harm, can not be sprayed, in order to protect more natural enemies. It is also possible to carry out the relocation and release of natural enemies to eliminate aphids. The natural enemies of aphids include ladybirds, grasshoppers, aphid cocoon bees, aphids, aphids and so on.
2. Drug control is mainly in the spring peach blossoms and aphid eggs have all hatched, but there has not been a large number of multiplication and spraying before leaf curling. Aphids are susceptible to drug resistance and should often switch to pesticide use. It can spray 30% peach spirit emulsion 2500 times liquid; or 50% octyl thiophos 2000 times; or 50% aphid pine powder 1500 times liquid; or 50% parathion 1000 times liquid; or 50% dichlorvos 1000 to 1500 times liquid; or 40% Lego emulsion 1000 times liquid; or 20% killing chrysanthemum 3000 to 5000 times liquid, all have good results.
3, strengthen the winter Qingyuan in the winter after the winter shaping and pruning, to carry out a comprehensive clearance of the orchard, burn the ground leaves and pruned branches; orchard combined with winter fertilization for ploughing, increase soil permeability and kill overwintering diseases and insect pests in the soil; do a good job in whitening the trunk of fruit trees, and at the same time spray a 3-pohmed stone sulfur compound before budding, or spray diesel emulsion to kill wintering insect eggs and reduce the harm of spring aphids.