Have you ever found small white worms inside litchi fruits? Well, those little worms are called fruit borer and they are completely harmless. So, you don’t have to worry if you accidentally eaten one of them. Litchi fruit borer (Conopomorpha sinensis) is a moth (adult), belongs to family Gracillariidae (known as gracillariidae borer) of Lepidoptera order.
The adult moth lay eggs on underside of leaf or near the pedicel of litchi fruit. After some days milky white larvae with brown head develops from eggs and start to bore into the fruit. Since, the litchi fruit outer covering is rough texture, the larvae entrance can’t be seen easily. Only small black dot can be seen when examined closely. Otherwise, the fruit seems completely normal and fresh from outside while the larvae is developing inside. The larvae is most damaging stage of life cycle, it bore into the upper side of seed and start to feed on fruit pulp. Rain and humid weather favours the growth of larvae. Fully grown larvae comes out of fruit and pupate on older leaves forming spindle around it. After some time adult come out of the cocoon.
fig: Litchi fruit borer (Conopomorpha sinensis) damage symptoms on litchi fruit ( Photo source: my own)
- Field sanitation should be practiced by removing and destroying damaged fruits and seeds.
- Fruit wrapping or bagging can be done if the infestation becomes severe.
- Neem-based pesticides can be sprayed.
- For bio-control, Trichogramma chilonis can be used.