Effect of different locally available botanicals against stored cocoon pest, Dermestid Beetle

Abstract:

The study was conducted to evaluate the effect of different locally available botanicals on the mortality percentage, repellency, antifeeding effect and emergence of Dermestid species. The test botanicals were screened at different concentrations (5%, 10% and 20%) at different time intervals. The treatment details were T₁ (5% Capsicum annum), T₂ (10% Capsicum annum), T₃ (20% Capsicum annum), T₄ (5% Artemesia absinthium), T₅ (10% Artemesia absinthium), T₆ (20% Artemesia absinthium), T₇ (5% Datura stramonium), T₈ (10% Datura stramonium), T₉ (20% Datura stramonium), T₁₀ (5% Pyrethrum), T₁₁ (10% Pyrethrum), T₁₂ (20% Pyrethrum) and T₁₃ (Control). Significantly the highest mortality percentage (97.83%) was recorded in T₃ (20% Capsicum annum) followed by T₁₂ (20% Pyrethrum) with mortality percentage of 81.93 percent at 72 hours after treatment and the lowest mean mortality percentage (13.33%) was found in T₁₃ (control) at 72 hours after treatment. The maximum mean repellency (40.21%) was observed in T₃ (20% Capsicum annum) followed by T₁₂ (20% Pyrethrum) with the mean repellency of 35.27 percent and the minimum mean repellency (5.37%) was observed in T₁₃ (control). Significantly the maximum antifeeding effect of treated silkworm pupae was observed in T₃ (20% Capsicum annum) followed by T₁₂ (20% Pyrethrum) and the minimum anti feeding effect was found in T₁₃ (control). The grubs treated with B1 (Capsicum annum) have shown significantly zero emergence percentage at all the concentrations (5%, 10% and 20%). However B4 (Pyrethrum) at 20 percent concentration did not differ significantly with B1 (Capsicum annum) at 20 percent concentration. From the above findings, it is concluded that the extract of Capsicum annum in the best bio-insecticide, it has the highest repellent and toxic effect against Dermestid species. Thus the application of eco-friendly and locally available Capsicum annum extract for disinfection of cocoon storage rooms/ bags can help the silkworm rearers/ reelers to reduce the post storage loss of silkworm cocoons.