Some problems with using biological agents under field conditions are their susceptibility
for sun radiation and their incompatibility with commonly used chemical pesticides. This is often due
to the use of no or poor formulations. When photostability of a previously developed biocontrol
product based on a Lecanicilllium lecanii isolate was evaluated by exposure to sun radiation, a
reduction of 69.7% in the germination of non-formulated L. lecanni (VL026) conidia was obtained,
compared with 37.4% reduction observed with the formulated conidia, six hours after exposure to
radiation. Chemical pesticides, like Chlortalonyl, Diphenoconazole, Carbofuran and Dimethoate were not compatible with the fungus, whereas Sulfur, Cooper Oxichloride, Propiconazole and
Carboxyn-Captan showed some compatibility. Under laboratory conditions, formulated and nonformulated conidia produced a80.6% and 69.1% mortality of B. tabaci nymphs, respectively.