How to prevent and control weevil infestation when growing mangoes?

1. The mango leaf-cutting weevil is widely distributed. Adults feed on young mango leaves, causing the leaves to dry up; or the female lays eggs on young leaves and bites the young leaves off at the base, affecting plant growth. Control methods:

① During the growth period of young shoots, pick up the fallen leaves bitten off from affected trees once every 3 days, dry them in the sun and burn them to kill the larvae;

② During the growth period of young shoots, spray once every 7 days. 40% dimethoate emulsifiable concentrate at 1500 times dilution, 90% trichlorfon at 1000 times dilution, 25% bisultap at 500-800 times dilution and 2.5% deltamethrin at 2004-3000 times dilution can all be used.

2. The fruit mango weevil and the flesh mango weevil. The former is a small beetle about 7 mm long, black in color. Its larvae bore into and feed on mango seeds, affecting fruit quality; the flesh mango weevil is a smaller yellowish-brown beetle than the fruit mango weevil, and its larvae mine the flesh, forming tunnels filled with insect frass, making the fruit inedible. These two pests mainly occur in Yunnan, Vietnam, Cambodia and as far as Indonesia, and are quarantine targets. However, reports indicate that in recent years this pest has been found in the border area between Guangxi and Yunnan. Because these two pests cause serious damage but occur only in limited areas, quarantine must be strengthened to prevent their spread to new areas. In recent years, the practice of transporting large quantities of mangoes from Vietnam through non-official channels without quarantine is dangerous.

Control methods:

① In areas where this pest has not been found, strictly enforce the quarantine system to prevent its spread to new areas;

② In infested areas, maintain good orchard sanitation, promptly pick up fallen fruit and poison them in a centralized manner;

③ In autumn and winter, combined with orchard cleanup, remove all weeds, plow finely, and eliminate pests overwintering in cracks in the soil layer;

④ During the young fruit stage 30-45 days after petal fall, spray the tree canopy with a mixture of dimethoate and trichlorfon with water at 1:1:1500, spraying once every 7-10 days; 3-4 consecutive sprays can achieve significant control efficacy.