Bioactive Potentials of <i>Cassia renigera</i> Benth. Extracts against the Stored Product Pests <i>Callosobruchus chinensis</i> L., <i>Sitophilus oryzae</i> L. and <i>Tribolium castaneum</i> (Hbst.)

Abstract

Petroleum (Pet.) ether, CHCl 3 and CH 3 OH extracts of Cassia renigera Benth. were tested against Callosobruchus chinensis L. for dose-mortality and repellency; and against Sitophilus oryzae L. and Tribolium castaneum (Hbst.) for repellent activity test. The Pet. ether extract of leaf was found active against C. chinensis adults through dose mortality assay and the LD 50 values established were 9.270, 4.932, 2.032, 1.721, 1.671, 1.543, 1.513, 1.503 and 1.478 mg cm -2 for 0. 5,6,12,18,24,30, 36, 42 and 48 h of exposure respectively. However, the leaf extracts of CHCl 3 and CH 3 OH; as well as the Pet. ether, CHCl 3 and CH 3 OH extracts of the stem-bark did not give mortality to the test organism. The CHCl 3 extract of leaf showed repellent activity against Tribolium castaneum at 0.1% level of significance (P < 0.001), and the Pet. ether extracts of the leaf and the CH 3 OH extracts of the stem-bark offered repellency at 1% level of significance (P < 0.01) between dose levels. Only the CHCl 3 extracts of the stem-bark gave repellency at 5% level of significance (P < 0.05), while the CH 3 OH extracts of leaf and Pet. ether extract of stem-bark did not show any significant repellency at all.