author(s)
Hasan Ali, Meherun Nesa, Shahina Begum Rekha and Nurul Islam

abstract
Petroleum ether (Pet. ether), Chloroform (CHCl₃) and Methanol (CH₃OH) extracts of seeds, aerial part, and roots of A. mexicana L. have been screened thoroughly for their insecticidal and repellent activity against the stored grain pests Sitophilus oryzae L. and Callosobruchus chinensis L. under laboratory conditions. The Pet. ether, CHCl₃ and CH₃OH extracts of the aerial part and roots did not offer any mortality at all, while the seed extracts of Pet. Ether, CHCl₃ and CH₃OH were found active and gave LD₅₀ values against S. oryzae and C. chinensis. According to the intensity of activity of the seed extracts could be arranged in the descending order of: Pet. ether > CHCl₃ > CH₃OH against S. oryzae and CHCl₃ > Pet. ether > CH₃OH for C. chinensis. For repellency test against S. oryzae the Pet. ether extract of roots and seeds have shown significant result at 5% level of significance (P<0.05), and also the Pet. ether extract of roots and aerial parts, and CH₃OH extract of roots shown repellent activity against the adults of C. chinensis at 5% level of significance (P<0.05); but the CHCl₃ extract of the roots, aerial parts and seeds; CH₃OH extract of the aerial parts and seeds didn’t show any repellent activity against S. oryzae and C. chinensis.