Whitefly Parasites-Biological Control
The encarsia is a small tropical wasp which does not sting humans. They kill the whiteflies internally. An adult encarsia will lay her eggs inside whitefly larvae which will kill parasitically them as the eggs develop. Each adult encarsia can lay up to 200 eggs. Adult encarsia also benefit the plants by feeding on the honeydew left by the whiteflies which reduces the likelihood of mold developing on the underside of the leaf.
Ladybugs also can be helpful in controlling whitefly populations. They feed primarily on the eggs, but can also feed on larvae. Ladybugs can live and be effective for about a year, however they tend to move around so you may not reap their benefits for the entire year. To combat this, a sticky substance can be used on the underside of their wings to inhibit their ability to fly which will keep them closer to where they were released.
Introduced as eggs or larvae, green lacewings will attack whitefly eggs and larvae with vigor. They work more quickly than Ladybugs and Encarsia, however they are only effective as larvae. Adult green lacewings eat only nectar and pollen. Green lacewings stay in their larvae stage for a week to three weeks. Due to this short time frame, they may need several applications before the whitefly problem is solved.