Nk. Maniania, EFFECTIVENESS OF THE ENTOMOPATHOGENIC FUNGUS BEAUVERIA-BASSIANA (BALS) VUILL FOR CONTROL OF THE STEM BORER CHILO-PARTELLUS (SWINHOE) IN MAIZE IN KENYA, Crop protection, 12(8), 1993, pp. 601-604
The fungus Beauveria bassiana (Bals.) Vuill. and insecticide trichlorf
on were compared for the control of stem borer, Chilo partellus (Swinh
oe) in field experiments at different times of infestation. Egg masses
of C. partellus at the blackhead stage were pinned to the undersurfac
e of the maize leaves. Two fungal formulations, conidial aqueous suspe
nsions and a granular formulation, were applied. Compared with the unt
reated checks, the numbers of surviving C. partellus larvae were signi
ficantly reduced in treatments where B. bassiana was applied at a conc
entration of 10(13) conidia ha-1 as granules and as two aqueous spray
formulations. No significant difference in numbers of stem borer larva
e was found between trichlorfon and the untreated check. Fungus granul
es persisted longer in the field than did one spray of the fungus inoc
ulum at the same concentration, or trichlorfon. A major increase in gr
ain yield was obtained with two fungal sprays and with fungus granules
both applied at a concentration of 10(13) conidia ha-1. A granular fo
rmulation of B. bassiana should be considered for the control of the s
tem borer C. partellus.