Toxicological and physiological effects of allyl isothiocyanate upon Callosobruchus maculatus

This study aimed at evaluating the toxicity of allyl isothiocyanate (AITC) to adults of Callosobruchus maculatus (Fabricius) (Coleoptera: Chrysomelidae) and its effects upon oviposition rate, population development, respiration rate, and dry mass loss in cowpea beans. The toxicity of AITC was determined by applying lethal concentrations (LC) of the compound, whereas the mortality curves were drawn by utilizing increasing concentrations of AITC (from 5.0 to 13.33 mL m⁻³ of grains). Population development was assessed through oviposition, progeny and both daily and accumulated emergence at sublethal concentrations (LC₁ = 3.81 mL m⁻³, LC ₁₀ = 5.71 mL m⁻³, LC ₃₀ = 7.67 mL m⁻³, and LC ₅₀ = 9.41 mL m⁻³). Furthermore, the loss of dry mass in grains and the respiration rate of adults when exposed to AITC (LC₁, LC₁₀, LC₃₀, and LC₅₀) were withal appraised. The values of LC ₅₀ and LC ₉₅ to adults of C. maculatus were of 9.41 and 17.85 mL m⁻³ of grains, respectively. At sublethal concentrations of AITC, the respiration oviposition, and emergence rates declined. The fumigant agent also prevented mass loss in cowpea beans. On account of that, it is safe to say that the compound has significant potential for controlling C. maculatus, inhibiting its development in storage conditions.