A number of natural enemies attack whiteflies including parasitic wasps, predatory beetles and mites, and fungi. Some of them have been used successfully in biological control. An example for South Africa is the control of the spiny blackfly (Aleurocanthus spiniferus) on citrus by a tiny species of parasitic wasp.
Biological solutions by employing White fly natural enemies are not always successful “Because natural enemies need a continual supply of food, they will never completely eliminate whitefly populations. Rather they are used to suppress pest populations to a level that is tolerable, i.e. there is no significant impact on the crop.(Horticulture New Zealand, Peter E. Smith, 2009).
Another approach which has shown good results is by applying Silicon at certain level as supplement (it is actually a nutrient used by plants). Silicon increase plant “immune activity” by stimulating production of Salicylic Acid. It has been proven that if plant “defence” is improved the ability of the plant to resist diseases is higher, in the case of Whitefly as a carrier of aggressive diseases organisms, the plant may handle the attack more effectively.
Recently a new product (757organic insecticide- Agri-challenge), has been researched and tested in a trial conducted by Gerhard Steyn and concluded under the project title:
“The selectivity and activity of 737-TR against white fly on tomato when compared with Mospilan 20SP” The trial purpose was to determine the selectivity and efficacy of 737-TR as a full cover application against Bemisia tabaci on tomatoes in a glass house.
The trial results and conclusions were ,that:
After 3 weekly applications of 737-TR and by 7DA3T, almost total control of whitefly nymphs as well as flying adults (nymphs no further source for adults) were observed (99% control). This control was statistically on par with acetamiprid.
(Excellent aphicidal activity against green peach aphid (Myzus persicae) was also observed in this trial.)
The “war” against the Whitefly is in full steam and keeps scientists and growers looking for the solution to if not entirely irradiate the problem to at least reduce its effect to maintainable levels.