When is the critical period for grape mealybug damage? How can it be prevented?

The red grape scale insect generally produces 2 generations per year, and the larvae spend the winter in the thick bark of the tree stem, and the red grape injury period gradually develops in the second year, which has an adverse effect on the red grape. At the end of April, females gradually cause significant injuries. From the end of May to June, the first generation of larvae are in full ovitalization, and the larvae climb up to the opposite side of the leaf or the new shoots are fixed and immobile.

The second generation lays eggs from mid to late July to early to mid August, and turns to branches for wintering in October.

Before the migration of the scale insects, generally in September, grass targets are placed under the trees, so that the scale insects lay their eggs on the top, and the middle and late stages of centralized destruction, which can significantly reduce the number of insect populations! The scale insect winters in the old bark, so it can be watered permeable after digging the soil in spring, and it is best to submerge the bottom of the neck, and the relative density of the insect mouth will be reduced by more than half. Peeling off the old bark will expose the eggs of the scale insects, and the whitening effect of the main stem is very good.

Flowering is a key node to prevent scale insects.

Generally, spirolec ethyl ester has a long duration and can well prevent scale insects from entering the bag. In the case of opening, spray oxidized dimethoate in all directions, in addition, when the bud worm sticks out of the small red head, the effect is better when the bud worm is rubbed before spraying. After withering leaves or before germination, wipe the insect branches with 5 Baumé dimethoate or spray the whole plant.

In the incubation period of wakama (the flowering period of acacia trees cultivated in the open field in Northeast China), the following drugs can be sprayed to kill scale insects: 40 speed killing 1000 1500 times liquid, 40 rapid killing of 1000 1500 times liquid.

28 1000 1500 times of incopidine, 1000 1500 times of 40% tachyscale grams, etc. The above drug is added to the silicone material infiltrating agent 3000 times. After the early varieties are picked, they can be sprayed to kill scale insects, and before using chlorphospho, now we can select the ingredients that are allowed to be used in our country as much as possible.

The late-maturing species can't be sprayed in time, and they can tie up multiple grass targets around the time of the heatSoak it in water and throw it under a tree, where the scale insects will lay their eggs, and they can be taken and burned in winter.

During the dormant period, pesticides should be sprayed in time at this time, and the spraying position should also be paid attention to, and the spraying place should be as close to the ground as possible.

The month of June is a critical period; It is necessary to spray some related drugs, and remove the debris and leaves in the area in time.

Grape mealybugs mainly suck the sap from adults and nymphs under the skin of old vines and on the fine roots near the ground, and the affected areas form large and small mound-like protrusions. As the plant grows and gradually turns to new shoots, the surface of the twigs and fruit stalks is rough and uneven. It also secretes a layer of white sticky like cotton wool, which often attracts ants and black mold, contaminates the peel, and affects the appearance and quality of the fruit.

The growth of the victim tree is poor, the fruit becomes deformed, and in severe cases, the tree weakens and the yield decreases.

Grape scales: belong to the family Homoptera. There are mainly grape mealybugs, Kang's mealybugs, oriental helmet scales, wax-free mealybugs, etc. Nymphs and female adults infest branches and leaves or fruits, causing trees to weaken, branches to die, and inducing coal disease.

Control method: Spray 3 4 Baumé stone sulfur mixture after defoliation to before germination; or pine resin Zhenglu mixture 8 10 times shouted trapped band (3 Baumé) liquid, to clear the garden to kill scales. Spray 1500 times of 40% oxidation ruler in the nymph stage; or 50% of the pine borer 1000 times liquid killing.

Pest Name:

Kang's mealybug, also known as mulberry mealybug, pear mealybug, plum mealybug.

Harmful crops: grapes, apples, pears, peaches, plums, dates, plums, hawthorns, apricots, walnuts, citrus, figs, lychees, pomegranates, chestnuts, persimmons, tea, etc.

Harmful symptoms: nymphs and female adults suck the sap of buds, leaves, fruits, branches and roots, and the young branches and roots are often swollen and easy to crack and die. Young fruits are mostly deformed. Excretion of honeydew often causes coal diseases, affects photosynthesis, weakens tree potential, and decreases yield and quality.

Habits: 3 generations per year, mainly overwintering with eggs in various crevices of the tree body and soil and stone crevices near the base of the trunk, and a few overwintering with nymphs and fertilized female adults. When the host germinates and germinates, the overwintering nymphs begin to move, and the eggs begin to hatch and disperse, and the first generation nymphs bloom in mid to late May, and emerge from early June to early July, mate and lay eggs. The second generation nymphs hatch from late June to late July, peak from early to mid-July, emerge from early August to early September, mate and lay eggs.

The third generation nymphs begin to hatch in mid-August, enter the peak period from late August to early September, begin to emerge in late September, mate and lay eggs for overwintering; Prematurely laid eggs hatch and overwinter as nymphs; Those who are late in eclosion do not lay eggs after mating, that is, they overwinter. The female nymph stage is 35-50 days, and the male nymph stage is 25-40 days. After mating, the female adults feed for a short time to find a suitable place to secrete oocysts to lay eggs.

The number of single female eggs: 200-450 in the 1st and 2nd generations, 70-150 in the 3rd generation, and the overwintering eggs are mostly in the crevices of the tree. This insect can move at any time to become a pest.

Natural predators include ladybugs and grasses.

Prevention and control methods: 1Pay attention to protecting and diverting large enemies. There are ladybugs and lacewings.

2.When the initial spotting occurs, the insect stems and vines are manually brushed. 3.

Pharmaceutical prevention and control. In the nymph disperse transfer period, spray 2 5 dichloride or kung fu emulsifiable concentrate or 20 dichloride emulsifiable concentrate, 20 quick killing butadiene emulsifiable concentrate 3000-4000 times, 10 cypermethrin emulsifiable concentrate 1000-2000 times, 50 malathion or pine borer or rice Fengsan emulsifiable concentrate 1000 times, such as with oil content 0 3-0 5 diesel emulsion or clay diesel emulsion mixture, it has a good killing effect on nymphs that have begun to secrete wax powder shells, and can prolong the control period and improve the control effect. During the dormant period of fruit trees, combined with the prevention and control of other diseases and insects, it is best to use a hard brush to remove the overwintering insects in the crevices.

The prevention and treatment of dormant agents should be carried out after scraping.