Planthopper is the only vector of Huanglong disease how to control planthopper on citrus

Citrus planthopper is the only natural transmission vector of citrus Huanglong disease, so the strict control of citrus planthopper in a large area is the most important measure to control Huanglong disease.

Orange planthopper

Citrus planthopper transmission has four characteristics: first, the transmission rate of citrus planthopper is high, and the transmission rate of a single adult is as high as 7080%; second, it carries the disease for life, and the nymph does not disappear with molting after obtaining the pathogen of citrus Huanglong disease. Third, it spreads with the wind, and the adult can fly 7 meters high and spread in close range with the wind; fourth, it spreads quickly. These characteristics determine that in order to control Huanglong disease, it is necessary to kill wood lice quickly and effectively.

The prevention and control of citrus planthopper should be based on prevention, and should not wait until the planthopper is found. If you spray wood lice only when it is found in citrus orchards, it is likely that the wood lice has spread Huanglong disease. At present, the control of citrus planthopper is mainly based on quick and efficient chemical control, supplemented by agricultural, biological and physical control.

Spraying chemical pesticides is still the most important measure to control citrus planthopper. The key period of spraying is the clear garden in winter and the shoot emergence period in spring, summer and autumn. The planthopper only feeds on tender shoots, and the shoot stage is the high-risk period. Clearing the garden in winter can eliminate the overwintering adults of planthopper and reduce the population number in spring, which is the most critical period for the control of citrus planthopper in the whole year. During the shoot emergence period, when the length of the new bud 0.5~1.0cm, spray control, with the growth of the new bud, about 5-10 days, spray again. The main agents are 21% thiazine water suspension 3500 times, 25% quinathion EC 1000 times, 4.5% permethrin water emulsion 1500 times, 2.5% cyhalothrin water emulsion 1500 times, 51.5% high chlorine chlorpyrifos EC 1000 times, and so on.

It is worth noting that before cutting and digging Huanglong diseased trees, it is necessary to spray to kill wood lice adults to avoid hiding from healthy trees. After fruit harvest, the garden should be cleared immediately to kill wood lice. Kill wood lice in time after Taiwan wind and rain or after heavy rain. The adults of citrus planthopper can migrate over a long distance. In Taiwan wind and rain season and severe convective weather (May to September), the adults of citrus planthopper in the areas with serious Huanglong disease in the southeast will be blown up by the wind and moved over a long distance. Adults of wood lice near the Huanglong disease orchard will also be blown up by strong winds and fly into the orchard, so after typhoon and storm, spray immediately to kill wood lice when the weather is fine.

In addition, auxiliary measures such as agricultural physical control can also be adopted, such as the removal of wood lice host plants such as Jiuli incense and yellow peel around the citrus orchard. Pruning, fertilization and irrigation can promote the neatness and consistency of citrus shoots, shorten the time of shoots, and promote the ripening of new shoots.