BIOLOGICAL CONTROL OF YELLOW SUGARCANE APHIDS, SIPHA FLAVA (HOMOPTERA: APHIDIDAE) USING A COMMERCIAL STRAIN OF BEAUVERIA BASSIANA (HYPOCREALES: CORDYCIPITACEAE)

The yellow sugarcane aphid, Sipha flava (Homoptera: Aphididae) is a major insect pest of sugarcane in Eswatini. Insecticides are used to prevent honeydew build up and yield loss before harvest but they are not preferred due to resistance problems, disruptive effects on natural control of other sugarcane pests, pesticide residue and high production costs. The use of the entomopathogenic fungi as a biocontrol agent of sugarcane aphid is an environmentally friendly management tactic. The current study evaluated the mortality effects of four concentrations [Control, 1.25 g/L (2.5×106 spores/ml), 2.5 g/L (5×106 spores/ml) and 5g/L (1×107 spores/ml)] of commercially available Beauveria bassiana (Eco-Bb® ) strain R444 on adult yellow sugarcane aphids in laboratory and leaf bioassays. The application of 5g/L (1×107 spores/ml) of B. bassiana resulted in mortality that was not significantly different from 2.5g/L (5×106 spores/ml) but was significantly (P