Efficacy of essential oil from Clausena anisata and its impact on biochemical changes of Sitophilus oryzae.

Essential oil (EO), from Clausena anisata, was evaluated for their efficacy (fumigant and repellent activities) against Sitophilus oryzae. Result revealed that C. anisata showed 82% fumigant toxicity (insect mortality) at 160 µL/L concentration after 24h observation period. C. anisata exhibited LC50 value of 17.84 µL/L concentration for fumigant toxicity. The insect movement behaviour (repellent) was observed in two different concentrations of 10 and 50 µL for a period of 3 h. Maximum repellent activity (- 0.25) was observed at 50 µL/L concentration against S. oryzae after 3-h observation. At 3, 6 and 12 µL/L concentrations of C. anisata oil significantly reduced the protein content and total esterase activity of S. oryzae.

Toxic effect of Atalantia monophylla essential oil on Callosobruchus maculatus and Sitophilus oryzae.

The hydrodistillated essential oil of Atalantia monophylla was subjected to GC-MS. Forty compounds were presented in the essential oil. Eugenol (19.76 %), sabinene (19.57 %), 1,2-dimethoxy-4-(2-methoxyethenyl) benzene (9.84 %), beta-asarone (7.02 %) and methyl eugenol (5.52 %) were found the predominant compounds. The oil was tested for fumigant toxicity and repellent activity against Callosobruchus maculatus and Sitophilus oryzae. The development stage of C. maculatus fecundity, adult emergence and also ovicidal activities were studied by the treatment of A. monophylla oil. The oil exhibited considerable fumigation toxicity (70.22 %), repellent activity (85.24 %) and ovicidal activity (100 %) against C. maculatus. The oil significantly reduced the protein, esterase, acetylcholinesterase and glutathione S-transferase on C. maculatus and S. oryzae. It can be considered that A. monophylla has a potential insecticide against stored product pests.