Efficacy of Diatomaceous Earth and Insect Growth Regulators against Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae)
Muhammad Awais*, Mansoor-ul-Hasan, Muhammad Sagheer, Muhammad Usman Asif, Qurban Ali, Shah Zaman
Grain Research, Training and Storage Management Cell, Department of Entomology, University of Agriculture, 38000, Faisalabad, Pakistan
Among all stored grain insect pests, Tribolium castaneum causes huge economic losses. The current investigation was designed to evaluate the toxic and growth regulatory effects of diatomaceous earth (DE) and insect growth regulators (IGRs) alone and in combination against T. castaneum. Different concentrations of DE (200, 400 and 600 ppm) and IGRs (0.02, 0.04, and 0.06 ppm) were tested against T. castaneum. Maximum mortalities of 79.2%, 98.2% and 38.1% were recorded in case of DE, lufenuron and tebufenozide, respectively, at their highest dose rates. The combined treatment of lufenuron + DE showed maximum mortality of 98.2% at the highest dose rate (0.06 + 600 ppm). It was also observed that the highest doses of lufenuron, tebufenozide, DE and lufenuron + DE showed a significant reduction in larval, pupal and adult emergence of T. castaneum compare to control. Minimum mean pupation of 19 was observed at 600 ppm in case of DE, while for lufenuron, tebufenozide and combined treatment (lufenuron + DE), minimum mean populations of 13, 20 and 11.3 were seen at their highest dose rates, respectively. Minimum progeny production recorded in case of lufenuron + DE was 170 over 435 of control. The lufenuron and DE were found most suitable against T. castaneum, not only alone but also combined. Overall, the results of the present work clearly indicate that the combined use of DE and IGRs is highly effective against stored grain insect pests.