Preliminary Laboratory Evaluation of the Efficacy of Mixed Seed Powders of Piper guineense (Schum and Thonn) and Theueria penmiana (Persoon) Sebum Against CaIIosobndws .J Coleoptera: Brucbidae).
DOI:36108/NJE/7002/42.0141
EMEASOR. K. C. EIIOSAIRUE, S. O. AND OGBWI. R. O.
ABSTRACT. The prospect of controlling the cowpea bruchid, Callosobruchus maculatus (F.), with mixture containing Piper guineense (Schum and Thonn) (Pg) , and Thevetia peruviana (Persoon) Schum (Tp) seed powders in the ratios of 80:20, 60:40, 50:50, 40:60 and 20:80 was evaluated under ambient laboratory conditions (28±2°C and 75±20% R H). The mixtures of seed powders (500)lm particle size) were applied at the rate of 5% of the treated seed weight. Mortality of adult insects at 2 and 7 days after infestation (DAI), number of eggs laid and number of adults that emerged from each treatment were compared with those of the controls (PgO+TpO) (Pg100+TpO), and (PgO+Tp100). All mixtures, with the exception’ of Pg 20+Tp80, significantly (P<0.05) caused higher mortality to C. maculatus than the control (PgO+TpO). The mixture Pg80+Tp20 caused the highest mortality (56.36%) at 7DAI, had the least egg count (2.34120g seed) and significantly (P<0.05) suppressed adult emergence. The seed powder mixtures did not produce additive or synergistic effect on the parameters quantified.