An evaluation of the effect of four host plants on biological parameters of Maconellicoccus hirsutus and efficacy of Anagyrus kamali was conducted in the laboratory. Hibiscus rosa-sinensis and Hibiscus sabdariffa produced M. hirsutus with life cycles which were 1–2 days shorter than those of M. hirsutus reared on Solanum tuberosum, and Cucurbita pepo L. Egg to adult M. hirsutus survival was lowest in C. pepo (8.8%) and highest for H. sabdariffa (21.8%). C. pepo, H. rosa-sinensis and H. sabdariffa produced a more female biased M. hirsutus sex ratio from single ovisacs, than S. tuberosum. Although adult M. hirsutus females exhibited variation in size and longevity on the host plants tested, total fecundity was not significantly different. Life cycle of both sexes and offspring sex ratio of A. kamali emerging from M. hirsutus cultured on the four host plants were statistically similar. M. hirsutus infested H. rosa-sinensis and H. sabdariffa produced A. kamali with significantly higher fecundity (post emergence adult counts) and lower longevity compared to the other host plants. Females with largest femur (Mean length = 0.2950 ± 0.0053 mm) were produced by M. hirsutus infested H. rosa-sinensis. A. kamali efficacy measured by percent parasitization and percent adult eclosion was statistically similar for all M. hirsutus infested host plants tested.

This paper presents a preliminary report of Fusarium wilt of Roselle in the Nigerian savanna. Soil and plant samples were collected from eight experimental plots where plants showed Roselle wilt symptoms. Samples were analyzed for the presence of nematodes and wilt pathogens. The wilt causative organism Fusarium oxysporum was isolated together with nematodes of different genera. However, nematodes of the genus Helicotylenchus, Scutellonema and Hoplolaimus appeared to occur in higher densities than the others.