WHITEFLY EXTERMINATOR
(delphastus pusillus) Delphastus is a specialized whitefly pretador in the lady beetle family that controls Greenhouse whitefly (Trialeurodes vaporariorum), Banded-winged whitefly (Trialeurodes spp.), Sweetpotato whitefly, silverleaf whitefly (Bemisia spp.),Woolly whitefly (Aleurothrixus floccosus),Azalea and hibiscus whitefly (Pealius spp.),Cloudywinged, citrus and Rhododendron whitefly (Dialeurodes spp.),Citrus blackfly (Aleurocanthus woglumi). If whiteflies are scarce, they will also feed on other small arthropods, such as spider mites, broad mites and aphids. Development is about a month long. Eggs are transparent and are twice as long as they are wide. The adult beetles fly, while larvae are slow moving and travel from plant to plant on leaves. Females lay 2 - 6 eggs per day, and can lay over 300 eggs in their 65-day lifetime. Females must eat 100- 150 whitefly eggs per day to initiate and sustain egg laying. Larvae feed for 7 - 10 days. Older larvae migrate down the plant to pupate. Pupae are often found clustered along leaf veins on the undersides of leaves. A single beetle can consume as many as 10,000 whitefly eggs or 700 larvae during its lifetime. Introduce Delphastus in whitefly infested areas of the greenhouse as soon as whiteflies are detedted. Release the beetles at sundown on the day that they arrive with an inoculation of one beetle per 50 to 100 sq. ft. of canopy to establish them. Ideally, you should inoculate when there are less than six whitefly immatures per leaf keeping temperatures between 65 to 90 degrees F, while adults can tolerate a temperature of only 45 to 105 degrees F. Releasing a colony near each other and close to food works well to enhance mating and egg-laying of the first generation. Right when the 2nd generation begins to emerge, you can spread them around. At this point, you will begin to see control. If you don't spray a heavy infestation, the beetle will soon take over. Each generation is approximately 50-100 times more numerous than the one before it. Ocne 3 weeks have passed, 100 beetles can become 10,00 and when 6 weeks have gone by they become 1,000,000. Unfortunately, once that amount of time has soon gone by, the plants can be destroyed. Preferably, you should start early or knocking down with a short residual pesticide. Delphastus do not survive in the absence of prey,therefore should be released only after whiteflies are detected.
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