Control methods of small green leafhopper in organic tea garden

False-eyed small green leafhopper, commonly known as floating dust, is one of the main pests on tea trees. Due to its harm, the light bud leaves are damaged, the yield is reduced, and the heavy bud leaves are destroyed, resulting in loss of harvest. 1. Morphological characteristics of the false-eyed small green leafhopper belongs to Homoptera, Cicadellidae. The whole life goes through three stages of egg → nymph → adult. 1. The egg is crescent-shaped, about 0.8 mm long and 0.15 mm wide, initially milky white, gradually turning light green, and a pair of red eye spots can be seen through the front end before hatching. 2. The nymph is 5 years old. It was milky white at first and gradually changed from yellowish to green with the increase of age. The wing buds began to appear at the 3rd instar and reached the fifth ventral segment at the 5th instar. 3. Adult head to wing tip 3.1-3.8 mm, light green to yellowish green. There are mostly two green spots in the middle domain of the crown, and there is a pair of green circles on the front edge of the head, also known as false monocular eyes, compound eyes grayish brown. The small shield plate of the middle chest has white stripes and is engraved horizontally. The front wing is yellowish green, the base of the leading edge is green, and the wing tip is transparent or smoky brown. The foot is the same color as the body, but the ends of tibia and tarsus of each foot are green. Second, the harmful way is that nymphs and adults suck the juice of tender shoots and leaves, and the female adults lay eggs in the tender shoots, resulting in damage to the transport tissue, loss of nutrients and insufficient water supply. After the damage, the bud leaves withered, the leaf veins turned red, the leaf tip leaf edge turned red and even scorched, the internodes shortened and the texture became brittle, especially the second round tea suffered the most in the whole year. Third, the occurrence characteristics of the false-eyed small green leafhopper are tender, only endanger the tender shoots and leaves, are afraid of light and humidity, are not very active when the frost is not dry in the morning, and gradually transfer to the canopy after the sun comes out. Its adults are gradually pregnant, and the eggs are laid day by day. 1-2 eggs per day, so it is determined that its occurrence algebra is irregular, summed up in the following characteristics. The main results are as follows: 1. the annual occurrence algebra can occur for 13 generations a year in Guangdong, overwintering with adults in the north of Guangdong, and there is no obvious overwintering phenomenon in other places. 2. Adults and nymphs can be seen at the same time in overlapping generations and messy tea gardens. However, there are two peak periods in the whole year, the first from May to June and the second from September to October. 3. Climatic factors affecting air temperature, precipitation and rain days are the main climatic factors affecting the population growth and decline of false-eyed small green leafhopper. It is suitable to occur under the condition of average temperature 17-28 ℃, sometimes sunny and sometimes rainy. 4. There are more than 60 kinds of natural enemies, the most important of which are egg parasitoids, tasseled wasps, spiders, insect molds and so on. In addition, its occurrence and development is closely related to cultivation management and varieties. A single clump of white leaves suffers a lot.

4. control methods there are two different directions for the control of false-eyed small green leafhopper in organic tea garden, one is to adopt the method of ecological regulation, and the other is to rely on pheromone lure and control. 1. Ecological regulation and control the so-called ecological regulation is the use of agricultural cultivation and management measures, such as pruning and picking, to fully protect natural enemies, give full play to the role of natural enemies, and control the occurrence of small green leafhoppers. For example, seagull farms and warrior farms in Leizhou Peninsula adopt the method of ecological regulation and do not apply pesticides in more than 7000 mu of tea gardens. For more than a decade, small green leafhoppers have been controlled below the level of economic losses for a long time. The damage rate of bud and leaf is low, the population density is low, the species and number of spiders are many, and the parasitism rate of tassel wasp is high, which completely controls the small green leafhopper. This method is convenient, effective and low cost, and will not cause pesticide residue pollution in tea. Using the method of ecological control, there will be a certain risk in the initial stage of implementation, that is, the insect population will increase to a certain extent at the initial stage of stopping pesticide application, but there is no need to be afraid, when the population of natural enemies such as parasitic wasps and spiders increases, it can play a control role.