Apparently this whitefly is causing problems due to pesticide resistance
The “Q-Biotype” whitefly — discovered by Dr. Tim Dennehy, University of Arizona — has been in the trade journals recently. Specifically, Greenhouse Grower Magazine had an article by Lance Osborne, University of Florida, Scott Ludwig, Texas A&M Univeristy Extension, and Lin Schmale, Society of American Florists.
It’s since been mentioned elsewhere. Apparently this whitefly is causing problems due to pesticide resistance (see Insecticide Resistance Action Committee for more info) — which may make some folks wonder if it’s the whitefly that is the root problem, or whether it’s simply another let’s-takeover-Mother-Nature’s-job-by tinkering-with-things pesticide issue.
The Q-Biotype whitefly is Bemisia tabaci, a species we already mention on our site under Delphastus cataliniae, Eretmocerus eremicus, and under Whitefly Pests. It has been noted in the news articles that this biotype differs from the “B-Biotype” (which would be the “normal” B. tabaci but that wasn’t made clear to us) in only its resistance to pesticides as it was mentioned that visual differences are difficult to distinguish.
For years the B. tabaci species, also called the sweet potato whitefly, was effectively under the radar as the other “B-Whitefly” species as we say, B. argentifolii or the silverleaf whitefly, stole the limelight. The silverleaf whitefly was/is a major greenhouse pests, especially on poinsettia crops as mentioned in this article by Bastiaan Drees, Texas A&M University. In this article you’ll see a cross-usage of species names — this was pretty common just five years ago. Since then the determination has been made that the sweet potato whitefly and silverleaf whitefly are not only two distinct species, but two distinct genera as well. The Q-Biotype is a spin off from this it seems.
The reason for this article is not only to inform you of this industry news, but to also let you know that to those of you already using biocontrol, this isn’t really an issue. If you’re using D. cataliniae and/or E. eremicus and find you’re now dealing with the Q-Biotype whitefly, just keep doing what you’re doing and you should be all set. You don’t really have to be any more alarmed about this pest as you would any other. If you need identification, please visit this Special Info UFL Web Page. If you need more information about conventional controls, do see this Other Special UFL Web Page.
