What are the common species of citrus whitefly? Integrated prevention and control technology

Citrus whitefly is one of the common pests in citrus cultivation, once it occurs, it will have a great impact on the quality and yield of citrus. Therefore, it is necessary for growers to fully understand the pest. Let's take a look at what common species of citrus whitefly are. Integrated control techniques are attached.

What are the common types of citrus whiteflies?

There are 4 species of common whiteflies, and the most harmful whiteflies in China are whitefly and citrus whitefly.

The natural enemies of whitefly include C. whitefly, C. platyphylla, Aphis citri, Aphis ornate, Aphis aurantii, Aphis erythroides, Black wasp of whitefly, ladybug, Long hair mite with tumor, etc.

II. Causes of occurrence of citrus whitefly

1. Wide range of food and sufficient food sources

The citrus whitefly has a wide feeding habit and can feed on many kinds of plants such as Ligustrum lucidum and persimmon. Many varieties are mixed planted in the orange orchard. The growth period and management measures of different varieties are different. The new shoots are alternately sprouted. The tender leaves in the orange orchard are continuous and there are many kinds of intermediate host plants beside the orchard, which provide rich food sources for the citrus whitefly.

2, planting density is unreasonable

Citrus planting density is too high, crown closed, plant branches and leaves cross make light, temperature and humidity conditions conducive to pest growth, and because branches and leaves shield each other, affect the spraying effect.

3. The prevention method is unreasonable

Due to unreasonable use of chemical pesticides, excessive weed removal and other behaviors, natural enemies of whitefly such as Aphis formosana and Concha whitefly were killed, and the role of natural enemies in controlling citrus whitefly was reduced, thus causing a large number of whiteflies to occur.

4. Incorrect medication time

Because eggs and larvae are small in size, light in color, transparent and close to the color of branches and leaves, they are not easy to detect, often miss the best control period (egg incubation peak period), and only apply when adults appear, while adults are easy to migrate, mate on the back of leaves after appearance, lay eggs on young shoots, eggs and nymph protected by wax on the surface have strong drug resistance, and the spraying effect in adult stage is not ideal. The insect has many generations in a year, overlapping generations in the field, overwintering as larvae or pupae, and is difficult to control. In addition, orange orchards are mostly owned by individuals, control measures and time vary from person to person, and there is no unified organization for prevention and control.

3. Integrated control techniques of citrus whitefly

Agricultural control is the foundation, chemical control is the key, and unified control is the guarantee.

1. Reasonable pruning: combined with citrus pruning in winter and spring, thinning out over-dense branches, pest branches, improving ventilation and light transmission conditions, and reducing overwintering insect sources.

2. Yellow board trapping and killing: After adult emergence, hang yellow board to trap adults, hanging 35-40 pieces per mu.

3. Cleaning garden in winter: in the orchard where the insect occurs, turpentine mixture, sulfur mixture and engine oil emulsion are used to kill the overwintering insect source.

4. Chemical control: seize the key period of 1-2 instar nymph of citrus whitefly for key control. That is, in the peak period of egg incubation (late March, late May, mid-July to early August, early October), it is recommended to spray buprofezin, thiamethoxam, acetamiprid and other chemicals on leaves in the morning or evening.

When spraying, besides spraying the inner bore and leaf back of crown, we should pay attention to spraying weeds in orchard.