Autumn is the high incidence of many insect pests, especially in Sichuan, Guangxi, Yunnan and other mid- and late-ripening mango producing areas, during this time the plant is in the autumn shoots of the stage of extraction, the branches and leaves are young, there will be a variety of insect pests that like to eat young shoots, by eating young leaves for pests. It should be known that the autumn shoots of mango are the main resulting branches in the next year, if the autumn shoots are infested by insects, the light will lead to leaf damage, thereby affecting the photosynthesis of the leaves, hindering the accumulation of nutrients, affecting the normal differentiation of flower buds, and the heavy will lead to the whole autumn will be bitten off by insects, and the next year will have fruitless branches, which will seriously affect the second year's mango production.
Therefore, during the growth period of autumn shoots, it is necessary to observe the growth of fruit trees more and achieve prevention.
This article introduces the three main insect pests that occur in the autumn of medium and late ripening mangoes, hoping to help the majority of mango growers to do a good job in autumn pest control.
1. Leaf cutting weevil:
It is a coleoptera of the family Weeperaceae. Adults feed on the epidermis and mesophyll of young leaves, leaving behind nearly round nibbling spots, leaving only a transparent epidermis, which when the spots are joined together, cause the leaves to shrink and dry up. In the middle and late ripening mango producing areas, September is the most common period of adult insect occurrence, occurring 4-7 generations per year, overlapping generations, so autumn shoots are the most seriously affected. Female adults lay eggs on young leaves and bite off the leaves from the base, making neat incisions like knives, causing baldness and seriously affecting the normal growth of autumn shoots.
2. Leaf gall mosquito:
It is a diptera in the family Diptera, which is dominated by larvae infesting young leaves and shoots. It occurs in 5-8 generations per year, from April to early November, and after mid-November, the larvae enter the soil 3-5 cm and overwinter. Feathering was unearthed around the beginning of April of the following year, mating began on the night of excavation, and the next morning the female laid her eggs on the back of the young leaves, and the adults lived 2-3 days. The injured part is initially a small white dot, and later a brown spot, perforation is broken, the leaves are curled, and in severe cases, the entire leaf wilts and falls off to the ends.
3. Thrips:
It is a member of the order Thripsidae. In order to harm the young leaves, flower ears and young fruits of mango, 10-12 generations can occur in a year, with overlapping generations and coexisting insect states. Adults lay eggs in the dorsal veins or leaf flesh, and after hatching, the nymphs suck the sap on the back of the young leaves, causing the surface tissue of the young leaves to be contused and wood-thrombosed, resulting in discoloration of the leaves and seriously affecting the growth and development of young leaves of mango. The damage is worse during the dry season.
Prevention and control methods:
1. Strengthen field management, focus on prevention, comprehensive prevention and control; do a good job in clearing the garden, and deal with weeds and blight in a timely manner to reduce the base number of insect populations.
2. Pay attention to plastic pruning, properly prune and remove the closed branches, enhance ventilation and light transmittance, and reduce the incidence of insect pests.
3. Chemical control: in the early stage of leaf cutting weevil, it can be used to control Bo kill; in the early stage of the occurrence of leaf gall mosquitoes, it can be used to control yicheng and barbs; in the early stage of thrips, it can be used to use "kill + three kills" prevention and control.
Note: When mango new shoots are drawn, two key control periods are paid attention to, the first time is timely spray prevention when the new shoots are 2-3 cm, and the second time is spray control when the new shoots are about to turn brown.