Entomopathogenic fungi are ideal candidates for use as
microbial control agents as they can be mass produced and
sprayed onto crops using conventional equipment.10,11 However,
care needs to be taken when including entomopathogenic
fungi in biological control programmes to ensure that the
virulence, in vivo sporulation, recycling capacity, speed of kill
and persistence of the selected isolates are maximised while
virulence towards non-target insects and the effect of abiotic
factors (e.g. temperature, solar radiation and relative humidity) are
minimised.12,13 There are very few studies that specifically assess
the effect of entomopathogenic fungi on M. hirsutus. Although the
virulence of isolates of Beauveria bassiana (Bals.-Criv.) Vuill.14 and
Metarhizium anisopliae var. acridum (Driver and Milner)15 towards
M. hirsutus has been reported, other factors that may affect their
efficacy as microbial control agents, such as sporulation and
the effect of temperature on development, were not assessed.
Therefore, a series of experiments was performed to identify an
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