EFFICACY OF DIATOMACEOUS EARTH AND METARHIZIUM ANISOPLIAE (METSCHNIKOFF) SOROKIN AGAINST TRIBOLIUM CASTANEUM, RHYZOPERTHA DOMINICA AND SITOPHILLUS GRANARIUS

Abstract

The effectiveness of the entomopathogenic fungus Metarhizium anisopliae and Diatomaceous earth on the adults of stored grain insect’s species i.e.  Tribolium caustaneum, Rhyzopertha dominica, Sitophilus granarius were tested at the laboratory of Regional agricultural research institute Bahawalpur.  The tests were performed either alone or in conjunction with Grain guard (natural). A dosage rate of 1.7×104 was used for the fungal formulations, while 50 and 100 ppm of Grain Guard (Natural) were administered. The experiment was conducted at a temperature of 30 ± 1℃ and relative humidity of 65 ± 5%. In all treatments, mortality rate of insects was observed following exposure at intervals of 7, 14, and 21 days. After maximum exposure time, at a dosage rate of 100 ppm, T. castaneum, S. granarius, and R. dominica all reached maximum mortality rates of 70.49, 74.62, and 77.21, respectively, when treated with Grain Guard Natural. The corresponding mortality rates for T. castaneum, S. granarius, and R. dominica at lower doses of fungal spores were 26.35, 28.36, and 29.61, respectively. When the fungal formulations and Grain Guard Natural were used together at the maximum dosage rate of 100 ppm+1.7×104, 87.15 percent mortality was noted for T. castaneum, 92.35% for S. granarius, and 95.14% for R. dominica. For R. dominica, S. granarius, and T. castaneum, the proportion of mycotic insects was 81.86, 78.62, and 76.12 at a dosage rate of 1.7×104, respectively.