How they Attack
Creamy-white eggs are laid singly or in groups on the undersides of the leaves, on stems, flower buds, or the base of the fruit. The newly hatched larva prefers to bore directly into the fruit. When feeding is complete pupation occurs on stems, dried shoots, or among fallen leaves. Multiple overlapping generations occur in warm climates. This pest feeds on many other solanaceous plants such as tomato and potato. (http://www.avrdc.org/LC/eggplant/borer.html)
|Picture courtesy of avrdc.org|
Wilted shoots are readily visible. There may be small darkened holes surrounded with brownish areas on fruit surface and/or fruit stalk. The inside of the fruit is hollow and filled with frass. The fruit is not marketable.
Chewing mouthparts. The young caterpillar is dull white and turns light pink as it matures. It is 15-18 mm long. The adult moth is white with a pink or bluish tinge and brownish on its wings.
The article talks about which pesticides to use and in which quantities.
I really would recommend organic eggplant.