Whitefly is also known as the little white moth. Because whitefly has the characteristics of migratory and fertility, it is often difficult to control. In addition to directly harming plants, white powder can also spread plant viruses, causing harm indirectly. Through the observation and practice in the past two years, we have mastered the occurrence rules and prevention methods of greenhouse whitefly, and the control effect is obvious. Living habits: Adults have a tendency to tenderness, phototaxis, and yellow habits. As the plants grow, they spread to the apical and young parts to lay eggs, which makes the different insects have a certain hierarchical height distribution: from the top to the new green eggs And adult worms, black eggs that are about to hatch, early larvae, old larvae, and pseudo-caries are scattered in the back of the leaves. The nymph sucks the juice of the plant through the thorn, and the foot and the antennae degenerate after the second instar, until the pseudo mites are then emerged into adults. Occurrence law: Under the conditions of northern protected land and open field cultivation, whitefly mites occur 6 to 11 generations a year, with serious overlapping of generations, high survival rate, strong fertility, suitable temperature for breeding is 18 to 21 C, completed in the greenhouse. l It takes about 30 days for generations. The insect state cannot survive in winter under natural conditions in the north, but it can continue to reproduce in the greenhouse produced in winter. Hunchun moved to the outside of the greenhouse with the seedling transplanting, becoming the initial source of the arch shed and open field vegetables. Control measures: The prevention and control of whitefly mites should implement the principle of “prevention first, comprehensive prevention and control. The following prevention methods should be carried out continuously for 5 to 7 days, so that continuous hatching of adults will not be able to lay eggs, so they will be killed. In order to eliminate the source of the insects and avoid harm. 1. Eliminate the source of insects. Before the planting of the greenhouse or greenhouse crops, all the dead branches must be cleaned, buried or burned. Then use insecticide to select 1 000 times of omethoate at noon to kill eggs and nymphs, then use 80% of dichlorvos l 50 grams, water 14 kg, sawdust 40 kg, mix well and sprinkle into the ground, shack, Kill the adult completely. Such as high temperature shacks for about 1 day, all the insects in the shed can be killed. In addition, the planting nursery should be selected away from the vegetable field, cultivate no seedlings, seedlings with insects or eggs should be discarded, or use the liquid medicine to soak the eggs to kill the eggs, then select the source of white powder aphids The key link. 2. Lethal adults. According to the yellowish habit of whitefly, in the early stage of whitefly, the oil is coated with yellow plate and placed in the greenhouse, which is higher than the plant and traps the adult. 3. Biological control. If sporadic whitefly is found, each plant releases 3 to 5 heads of the black bee, which is released 3 to 4 times. The interval is about 10 days, and the parasitism rate is over 75%. The control effect is good. 4. Pesticides sprayed. After the spring, this method can be used when the temperature rises. The currently effective agents are: 125% chlorpyrifos WP 1500 times. 225% cockroach cockroach wettable powder 1000 times liquid. 32000 times liquid deltamethrin. 4 l 000 times the aqueous solution of laundry detergent. 520% dicofol emulsifiable concentrate l 000 times solution. 5. Fumigation fumigation. Using 22% chlorpyrifos aerosol to ignite fumigation, the control effect is more than 90%. The use of this method does not increase the humidity in the shed, and it is easy to promote. More pesticide knowledge , please pay attention to China Pesticide Network Independent Led Driver ,Led Built-In Power Supply,Independent Led Power Supply,Independent Constand Power Supply Effort Semiconductor Lighting Ltd. , https://www.effortem.com