Mango Pests and Diseases: Control Methods for the Oriental Fruit Fly

(1) Damage Also known as the oriental fruit fly, mango fruit fly, fruit maggot, yellow fly, etc. Adults lay eggs inside the skin of nearly ripe fruit; after hatching, the larvae feed on the flesh, causing fruit splitting, rotting and dropping. The surface of infested fruit remains intact, but on close inspection there are pin holes; when pressed by hand, juice oozes out, and when the fruit is cut open it is mostly rotted and full of maggots, unfit to eat.

(2) Morphological characteristics Adult body length 7-8mm, the whole body alternating deep black and yellow. On the head, the area between the compound eyes is yellow, the compound eyes are reddish brown, with 3 ocelli arranged in a triangle; the wings are transparent, the wing veins yellow-brown, the stigma triangular; the egg is prismatic, milky white, about 1mm long. The larva is about 10mm long, yellow-white, conical; the pupa is oval, pale yellow, about 5mm long and about 0.5mm wide.

(3) Life habits 3-5 generations occur per year, with overlapping generations and no obvious overwintering phenomenon. Adults emerge mainly around noon. After emergence, mating and egg-laying occur after about 20 days in summer, 25-60 days in autumn, and 3-4 months in winter; each female can lay 200-400 eggs, laid in several batches, with eggs deposited under the fruit skin and 5-10 eggs per egg-laying hole. The egg stage lasts 1 day in summer, 2 days in autumn, and 3-6 days in winter. After hatching, the larvae feed inside the fruit and molt twice. When mature, the larvae leave the fruit and enter the soil to a depth of 3-4cm to pupate.

(4) Control methods First, during winter or early spring, plow the orchard soil to reduce the overwintering pest population. Second, during the peak emergence period of adults, spray the tree canopy at night with a 2000-fold dilution of pyrethroid pesticides or a 800-fold dilution of 90% trichlorfon. Third, before the peak egg-laying period of adults, spray the dense parts of the canopy with a 800-fold dilution of 90% trichlorfon plus 3%-5% brown sugar, once every 7 days, for 3 consecutive sprays. Fourth, hang square blocks of bagasse fiber (57mm×10mm) soaked in methyl eugenol powder plus 3% bromophos solution on the trees during the adult occurrence period, hanging 50 blocks per square kilometer, twice a month. Fifth, starting from the mid-fruit-development stage, bag the fruit with paper bags to prevent adults from laying eggs on the fruit; collect infested fallen fruit and destroy it in a centralized manner; harvest fruit at the proper time to reduce damage.