Efficacy of local diatomaceous earth preparate (detech) against the rice weevil, Sitophilus oryzae and the lesser grai̇n borer Rhyzopertha dominica adults on wheat varieties

In this study, the insecticidal efficacy of local diatomaceous earth formulation, Detech at concentrations of 500 and 1000 ppm (mg Detech®/kg grain) was evaluated on bread and durum wheat varities against the Sitophilus oryzae (L.) and the Rhyzopertha dominica (Fabricius) adults. Based on the mortality results of R. dominica on the 21st day count in wheat varieties, the highest mortality rate for the 500 ppm Detech treatment was observed on the Burgos variety, while the Hamza variety had the lowest mortality rate. Similarly, for the 1000 ppm Detech® treatment, the highest mortality rate was recorded on the Burgos, Rumeli, and Zenit varieties, while the lowest mortality rate was observed on the Hamza variety. Regarding S. oryzae mortality results on the 21st day count in wheat varieties, Hamza variety exhibited the lowest mortality rate for 500 ppm Detech® treatment. For 1000 ppm Detech treatment, the Hamza variety also had the lowest mortality rate, whereas all other varieties showed 100% mortality. A mortality rate of 76% was observed in the Hamza variety after the 21st day of count. After the 21st day of count, all insects in the application bottles were removed, and biological tests were conducted to observe the emergence of F1 and F2 new adult generations. The effect of Detech® treatments on wheat seed germination were also determined under laboratory conditions. Consequently, this study revealed that the local diatomaceous earth, Detech has the potential for controlling stored grain insect pests since Detech® had the high efficiacy against R. dominica and S. oryzae adults on durum wheat and bread wheat varieties and suppressed their progeny production of F1 and F2 generations. Keywords: Local diatomoceus earth, Detech®, Rice weevil, Lesser Grain Borer, Wheat Variety