Treatment of rice with Neem and diatomaceous earth for controlling the stored-product Coleoptera, Sitophilus oryzae and Tribolium castaneum

The commercial available diatomaceous earth Fossil Shield(R) and the neem p roduct Neem Azal-T/S(R) are tested as single treatments and in combination as controls for the stored product pests Sitophilus oryzae (L.) and Triboli um castaneum (Herbst). The diatomaceous earth, applied in concentrations of 0.5 g, 1 g and 2 g kg(-1) rice, reduced numbers of surviving beetles signi ficantly (over a period of 3 weeks). A single treatment with the neem produ ct, in concentrations of 0.01 g, 0.1 g, 0.2 g and 1 g azadirachtin kg(-1) r ice, increased the mortality rate for both species significantly. The combi nation of neem and diatomaceous earth (1 g diatomaceous earth with 0.2 g or 1 g azadirachtin kg(-1) rice) was more effective than the single treatment in reducing numbers of surviving beetles.