Identification and control of major plum blossom pests

Aphidus serrata

It is a type of "sticky insect" that mainly sucks sap from tender shoots and young leaves. The insect overwinters as eggs on the branches and buds of plum blossoms. The wingless aphids that hatch when the plum blossoms sprout and unfold their leaves in March and April of the following year are the most harmful. The damage is severe in years with heavy rainfall and can induce sooty mold disease.

Prevention and treatment methods:

Spray with 2500 ml of 10% imidacloprid wettable powder; if aphids appear on a small number of plum plants in the home, you can dilute the juice of neem leaves and spray them, or sprinkle wood ash on the branches and leaves with aphids, and then rinse the branches and leaves with clean water after 1-2 hours.

Yellow-brown tent caterpillar

The larvae feed on tender buds, new leaves and leaves, and spin silk to form a tent-like web at the branches. They live in groups on the white tent. The mature larvae leave the tent and disperse to feed. In severe cases, they can eat all the leaves of the plant.

Prevention methods:

When the larvae are found clustered on the canopy, the net can be removed and the larvae can be burned to death; spray with 2500 times diluted 10% cypermethrin wettable powder or 3000 times diluted 2.5% Kung Fu emulsifiable concentrate.

Pink-necked longhorn beetle

The pink-necked longhorn beetle is the main pest that damages the main trunk of plum trees. There is often a pile of reddish-brown insect feces on the ground at the base of the plum tree that has been harmed by it.

Prevention and treatment methods:

In May and June, at noon on a sunny day after rain, look for adult insects resting on branches and kill them, or spray them with 3000 times diluted 2.5% Kung Fu emulsion; when fecal holes are found on the tree trunks, insert a poison swab into the holes to fumigate them, or use cotton wool dipped in DDT to plug the holes; in late autumn and early winter, whitewash the tree trunks.

Scale insects

There are many types of scale insects that harm plum blossoms, mainly including mulberry white shield scale, bran-flaked shield scale, pear round shield scale, Korean ball-hard scale, turtle wax scale, brown soft wax scale, etc. Among them, the Korean ball-hard scale is the most serious. Nymphs and female adults mainly gather densely on branches to absorb sap. In severe cases, the tree will be weakened, causing branches to die or the whole plant to die. It is also the main vector of plaster disease. When the pest occurs seriously, the infestation rate reaches 90% and the number of plum plant deaths accounts for 85% of the total deaths.

Prevention and treatment methods:

During the peak egg hatching period in early to mid-May, spraying with 1000 times diluted 50% carbofuran, 500 times diluted 50% malathion, or 500 times diluted 40% acephate + 2000 times diluted pyrethroids, all of which have good killing effects on nymphs; spraying with 2000 times diluted 75% cypermethrin wettable powder also has a certain effect on the control of Korean scale.

Red Spider

That is spider mites. Plum blossoms are widely affected and the damage is quite serious. It damages the back of leaves as adults and nymphs. Initially, small yellow-white chlorotic spots appear on the front of the affected leaves. Later, the chlorotic area expands, and the leaves lose their luster. In severe cases, they turn pale and cause premature leaf fall. Adult mites are oval in shape, red when first molting, and turn dark red after feeding. They are about 0.5 mm in size, while nymphs and young mites are slightly smaller. This insect has more than 10 generations a year, and overwinters as eggs and adult mites in the cracks of the rough bark of branches and trunks and among the fallen leaves. The most serious problem is during the drought from May to July.

Prevention and treatment methods:

Spray with 2000 times diluted 25% Beleba wettable powder; or spray with 2500 times diluted 20% Metoclopramide emulsifiable concentrate; or spray with 1500 times diluted 5% Nisoran emulsion. Because the insect body is small and hides on the back of the leaves, you must be careful and even when spraying, and rotate different miticides.

Bagworm

That is, "hanged ghost". The moths that harm plum blossoms and plum fruits include the large bag moth, small bag moth, tea bag moth, and white bag moth. The larvae are wrapped in a silky sac with larger broken leaves or a few randomly arranged branches and stems attached to the outside of the sac. There is one generation per year, and the mature larvae overwinter in the sac; they pupate in April and May, emerge from their shells at the end of May, and the larvae hatch at the peak in early June. In November, the mature larvae overwinter again in the sac. Newly hatched larvae crawl out of the mother sac at noon on a sunny day, spin silk and hang down, which are spread by the wind, and spin silk to attach leaves to form sacs on suitable plum trees or other plants. The larvae hide in the sac and carry the sac when migrating to feed. At first, they feed on the leaf pulp, leaving the upper epidermis, making the leaves appear as transparent spots. When they grow up, they eat holes or notches in the leaves, and even gnaw on the epidermis of the stems and chew the pulp. The damage is particularly serious when high temperature and drought last for a long time.

Prevention and treatment methods:

In autumn and winter, pruning should be combined with manual removal of sacs to eliminate overwintering mature larvae; use black light to lure and kill adult insects; spray larvae with 1500 times diluted 25% carbendazim No. 3; during the peak period of young larvae, spray larvae with 1000 times diluted 50% malathion; during the peak egg-laying period, spray with 1000 times diluted cotton bollworm nuclear polyhedrosis virus suspension at 2 billion/g.

Lignum moth &

That is "foreign spicy". The moths that harm plum blossoms include the yellow moth, the beautiful green moth, the green moth, the flat moth, the flat yellow moth, and the brown-edged green moth. In summer, the larvae feed on the leaves. In severe cases, the leaves may be eaten completely, leaving only the thick veins and petioles, affecting the normal growth, bud formation and flowering of the plum plant. The larvae have many poisonous hairs on their bodies, which are extremely irritating to human skin. Once they come into contact with human skin, they will produce a strong burning sensation.

Prevention and treatment methods:

In autumn and winter, the overwintering cocoons on branches are manually removed; during the emergence period of adults, they are attracted to light and killed by taking advantage of their strong phototaxis; potted plants are sprayed with 500 times diluted 0.3% azadirachtin, 2000 times diluted 25% chlorpyrifos 3, or 1500 times diluted 5% cypermethrin emulsion.