And if you find one that is parasitized with the wasp, don t spray it. The wasps are beneficial insects that can infest other hornworms after they mature. Bt will also kill the Colorado potato beetle larvae. For the adult, though, you can spray with pyrethrins, diazinon, methoxychlor, or carbaryl. Leaves are mottled and yellowing, and a puff of white insects arises if the plant is tapped.
Whiteflies are tiny white insects that feed on plant sap.
Spray with insecticidal soap, pyrethrins, malathion, or diazinon. You can also set out yellow sticky traps whose color will attract them. Nematodes are microscopic worms that live in the soil and feed on plant roots. If you pull the plant out of the ground, you ll notice that the roots are swollen and distorted. Leaves have light and dark mottling on them.