![]() All the evidence suggests that weevils spread into clean areas through the movement of infested fruit for propagation and consumption. No parasites or predators of eggs or larvae have ever been recorded.Īdult weevils can fly, but are not known to be strong fliers and do not move far from the tree where the fruit drops. Although many eggs have been seen on the surface of fruits, usually only one to a few larvae develop in the seed, indicating that significant numbers of eggs fail to hatch or young larvae die. Pupation occurs in the seed and adults emerge after chewing through the seed coat any time up to two months after fruit fall. In the seed the larva grows as it feeds on the cotyledons or seed leaves, causing conspicuous damage. The larvae tunnel into the fruit through the flesh and reach the seed in one to two days where they complete their development into adults. ![]() Older larvae (instars) are compact and C-shaped, typical of weevils. Several eggs may be laid on each fruit and each female can lay up to 15 eggs per day and up to 300 eggs during the season.Įach egg produces a white, legless and elongated slender grub which appears atypical of weevil larvae. This helps to protect the eggs and adheres them to the fruit. At laying, the weevil cuts a very small nick into the fruit and the resulting sap flow covers the egg case. The egg has a protective brown covering with two tiny tails at one end. Female weevils lay eggs over a number of weeks and egg-laying can continue in the orchard until a month before harvest. Adult weevils can live for two years, so even with a crop failure in one season some weevils can survive into the following year.ĭuring flowering the adult weevils leave their sheltered areas under loose tree bark and litter under the trees and move into the outer canopy of the tree to feed on new growth and to mate prior to egg-laying.Įggs are first laid on small young fruit about 30 mm in size. They may also live in leaf litter around the tree and approximately 25% of the adults over-winter in the seed. Weevils spend the winter living under loose bark around the base of mango trees or in the forks of branches. They possess typical weevil features and a tough exoskeleton. Scientific nameĪdult weevils are dark brown to black with grey markings and are 6-9 mm long. olivieri are found in some other mango producing areas around the world. ![]() mangiferae is the only species of weevil found in Australian mangoes, several other species including S. Mango seed or nut weevil ( Sternochetus mangiferae) has only one known host, cultivated and wild Mangifera spp.
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