The harm and control of whitefly

Whitefly is one of the common pests of plants such as seedlings, hedgerows and flowers, which seriously affects the normal growth of plants. Moreover, with the widespread use of pesticide products, resistant whiteflies began to appear in large numbers, and the difficulty of prevention and control has further increased!

Hazard characteristics of whitefly:

Whitefly is characterized by fast spreading speed, wide host range, strong reproduction ability, and high degree of damage. The adults and nymphs gather on the back of the plant leaves to suck the sap. The adults like to gather on the back of the tender leaves on the top of the plant. Eggs and nymphs gather on the middle and lower leaves of the plant. After the leaves are damaged, they will become green, yellow, wilted, and dry. Result in plant death. In addition, the honeydew it secretes can contaminate leaves and fruits, causing coal pollution. As the transmission medium of plant viruses, adults can transmit viral diseases.

 Conditions for the occurrence of whitefly:

1. Sufficient places for overwintering:

Due to the rapid development of sunlight greenhouses, and the planting of whiteflies like eating plants, it not only provides ample wintering places for the whiteflies, but also provides sufficient food, and provides a sufficient source of insects for the outbreak of the next year.

2. Human factors:

Whitefly on the greenhouse plants in winter continues to reproduce and harm, without diapause or dormancy. The opening of windows for ventilation in the greenhouse or the transplanting of vegetable seedlings move the source of insects from the greenhouse to the open field, leading to the spread of whitefly.

3. The host range is wide and the prevention and control is difficult:

Whitefly not only harms most plants, but also damages a variety of farmland weeds. It has the characteristics of wide host range, mixed feeding, large egg production, fast reproduction, strong drift, short life cycle, and large spread. Great difficulty in prevention and treatment.

4. Close connection between protected field cultivation and open field production:

Whitefly continues to occur from spring to autumn, and its population is suppressed due to the high temperature and rain in summer, but it is not obvious, and reaches its peak in autumn. The close connection between the greenhouse and the open field and the continuous planting of plants have led to an annual occurrence of whitefly.

5. Strong drug resistance:

Due to the long-term use of pesticides, whitefly has many generations and reproduces quickly, it has strong resistance to conventional pesticides, especially carbamate, organophosphorus, and pyrethroid pesticides. At the same time, long-term irrational use of drugs and single-family and single-site prevention and treatment are difficult to improve the overall prevention effect. Therefore, in the prevention and treatment process, it is necessary to rotate the medication to achieve unified prevention and control.

6. Strong adaptability:

Drought and little rain are suitable climatic conditions for the occurrence of whitefly, which often break out from June to September. The survey results in 2004 showed that the development of the whitefly population is not closely related to the rainy weather. The precipitation in July reached 324.7mm, which was 74 mm more than the same period in 2003 and 82.7mm more than the same period in normal years. However, the incidence of whitefly in August was still Larger.

 How to effectively prevent whitefly?

1. Biological control: It can be artificially propagated and released aphids. Parasitic wasps can establish populations in the greenhouse, and can effectively control the harm of whitefly.

2. Chemical control: when the whitefly is harmed, a 150 kg spray of Qilin Guangzheng can be used for prevention and control.