Comparative and combined toxicity of some microbial, chemical and botanical pesticides on Haplothrips tritici (Thysanoptera: Phlaeothripidae) in laboratory conditions

The combination of biological and chemical insecticides is very important to control wheat thrips ‎and reduce the dose of chemical insecticides. Therefore, in this study, insecticidal activity of botanical ‎‎(Tondexir and Palizin) and microbial pesticides (Bacillus thuringiensis (B.t)) in comparison with chemical ‎‎(Thiacloprid and Thiacloprid+Deltamethrin) insecticides on wheat thrips was investigated.‎‏ ‏A completely ‎randomized experiment was performed with three replications and five concentrations of each insecticide. ‎Based on the lowest LC50, a chemical insecticide and a botanical insecticide were selected. Their LC15 and ‎LC30 concentrations were combined with microbial insecticide and 48 h later, the mortality was calculated. ‎Mortality increased with increasing concentrations of chemical and botanical insecticides. The lowest ‎amount of LC50 was related to Thiacloprid+Deltamethrin and Palizin which were used in combination with ‎microbial insecticide. The highest mortality (76.67%) was related to the combination treatment of ‎B.t+Thiacloprid+Deltamethrin LC15, which can be recommended after field studies as a alternative‏ ‏of ‎chemical insecticides‏ ‏to protect wheat against thrips.‎