ABSTRACT
Toxicity to the insect growth regulators (IGR) chlorfluazuron, triflumuron, diflubenzuron, lufenuron and methoxyfenozide was evaluated against larvae of the lesser mealworm, Alphitobius diaperinus (Panzer) in laboratory conditions. Larvae were separated into 2 groups according to their body length as middle larvae (0.7 cm) and large larvae (1.3 cm), fed with rabbit food treated with concentrations between 1.6 and 200 ppm to active ingredient (i.a). The LC50 was estimate using Probit analysis. The most actives products were clorfluazuron (LC50 values ranged from 21.7 to 31.3 ppm/g diet) and lufenuron (LC50 values ranged from 21.1 to 64.4 ppm/g diet). The LC50 for triflumuron (111.2 ppm/g) and diflubenzuron (145 ppm/g) were 3.6 and 4.6 times, respectively, higher than that for chlorfluazuron. Diflubenzuron and methoxifenozide were less toxic. Methoxifenozide in the concentrations of 160 ppm/g of the diet caused a mortality of between 9.9 to 33.3%. At the same concentrations mortalities by diflubenzuron was from 39.9 to 53.3%. Chlorfluazuron, lufenuron and triflumuron demonstrated promising results for future tests in poultry houses.
KEY WORDS
Lesser mealworm; triflumuron; chlorfluazuron; methoxyfenozide; toxicity