The Role of the Analogue Hormone Insegar 25 WP (Fenoxycarb) in Controlling Trogoderma Granarium (Everts)( Coleoptera: Dermistidae)

This study aimed to evaluate the effect of the insect growth regulator Insegar 25 WP (Fenoxycarb) on some life traits and population dynamics of the Khapra grain beetle Trogoderma granarium (Everts) , one of the most serious pests of stored grains. Three concentrations of the insecticide (0.2, 0.4, and 0.6 g/L) were used, along with a control treatment. Life table parameters were evaluated, including larval stage duration (Ld), pupal stage duration (Pd), adult lifespan (Al), probability of survival to adulthood (lx), fecundity (mx), generation time (T), net reproduction rate (R₀), self-increase rate (r), finite rate of increase (λ), total reproduction rate (GRR), generational survival rate (GNR), and some derived population indicators. The results showed that all concentrations significantly prolonged the duration of both the larval and pupal stages, and progressively decreased survival and fertility until reproductive capacity ceased at a concentration of 0.6 g/L. The net reproduction rate (R₀) decreased from 16.17 in the control treatment to 0.25 and then to 0.10, reaching zero at the highest concentration. Meanwhile, the self-increase rate (r) shifted from a positive value (0.063) to negative values, indicating population collapse. Comparison between GRR and R₀ revealed that reduced survival to adulthood was the primary factor in population collapse, rather than a decrease in theoretical reproductive capacity. These results confirm that fenoxycarb is a promising and relatively safe growth regulator for the environment and public health, and can be incorporated into integrated storage pest management (IPM) programs, particularly when combined with non-chemical preventative measures.