How to deal with the eggs of litchi stink bugs? The flat-bellied wasp still needs to be matched with physical control methods.

Recently, the weather and temperature have gradually increased, and a large number of litchi stink bugs have been reported to be active and multiply all over Taiwan. As the litchi stink bug will reduce the fruit yield of longan and litchi, farmers often use pesticide spraying and manual pest control, or release flat-bellied wasps to control the number of litchi stink bugs. Wu Yihui, an assistant researcher at the Miaoli Agricultural Reform Farm, said that after releasing flat-bellied wasps, farmers must also use physical control measures to effectively reduce the number of litchi stink bugs. If people do not get flat-bellied eggs, the control effect can also be achieved by removing litchi stink bug eggs.

Wu Yi-hui explains that litchi stink bugs usually start their activities when the temperature picks up in March, and from March to June they enter the season of mating and spawning. As the climate gradually gets hotter, Taiwan has gradually entered the peak period of spawning. Because the litchi stink bugs live on the sprouts of litchi and longan trees or the sap of flowers, it will affect the production of litchi and longan trees, and when disturbed by external forces, the litchi stink bugs will secrete stinky fluid from their own glands, which may cause redness, swelling or burns to the skin if touched inadvertently.

At present, there are three control methods for litchi stink bugs, which are chemical, physical and biological control methods respectively. Wu Yihui pointed out that when longan and litchi are not yet in blossom, insecticides are applied when the adult activity is weak. During the period of mating and spawning from March to June, in order to avoid accidental injury to pollination insects during flowering, farmers can use physical control to knock off the litchi stink bugs on trees after wearing protective equipment. And remove the egg pile of litchi stink bug, wrap it tightly in plastic bags and treat it as general garbage.

As for the method of biological control, it is to use flat-bellied wasps. Wu Yihui says that during the period when litchi stink bugs lay eggs, hang pieces of paper adhering to flat-bellied wasp eggs on trees, or use drones to spread bee eggs after the flat-bellied wasps hatch. make use of the characteristics that flat-bellied wasps will parasitize to other biological eggs, so that the eggs of litchi stink bugs cannot hatch and die. Although biological control can reduce the hatching number of eggs, it still needs to be combined with the way of removing eggs in order to effectively reduce the population number of litchi stink weevil.

Wu Yihui said that this year, under the coordination of the Prevention and Inspection Bureau, it plans to release a total of about 16 million flat-bellied wasps in Taiwan. at present, the release has been completed in Kaohsiung, and other areas will be released one after another. at present, there are three channels in Taiwan that can buy flat-bellied eggs, namely, Bimai Company, National Taiwan University Agricultural proving ground, and Miaoli Agricultural Reform Farm, but it takes 2 to 3 months to produce flat-bellied eggs. And biological products have no shelf life, and now there is almost no stock of bee eggs. People can remove the leaves with litchi stink bug eggs, wrap them in garbage bags and throw them into the dustbin, which can also achieve the effect of prevention and control.