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Sorghum chafer, Pachnoda interrupta (Olivier) is a damaging pest of sorghum, other cereals and horticultural crops in Africa which results in complete crop loss. Currently, the management strategies rely heavily on chemical pesticides, which do not provide effective control. There is evidence showing that microbial biocontrol agents have the potential to control P. interrupta. In this study, the entomopathogenic fungi isolated from soils and insects in Ethiopia were identified using morphological and cultural characteristics. These were then evaluated for viability and virulence against Galleria mellonella (Fabricius) (Lepidoptera, Pyralidae) larvae and P. interrupta adults. Firstly, 116 Metarhizium spp. and Beauveria spp. were considered. The isolates were evaluated based on high viability as measured by percentage germination on SDA media. Only 56 isolates had greater than 70% viability. Secondly, these were further evaluated using conidial suspensions applied to G. mellonella larvae at a concentration of 1×10 8 conidia/ml. Four Beauveria spp. and three Metarhizium spp. isolates which caused over 60% mortality were selected for final virulence assay against adults of P. interrupta. The selected isolates were further confirmed by PCR amplification of ITS4 and ITS5 gene regions and chi1 and chi4 primers. Finally, the seven isolates were evaluated for virulence against P. interrupta at a dose of 1 mg dry conidia/10 beetles under laboratory condition. Mortality of P. interrupta ranged from 14% for isolate 9604 to 82% for isolate PPRC51. Dose-response tests showed that the LD 50 of PPRC2 (0.62 mg/10 beetles) and PPRC51 (0.55 mg/10 beetles) isolates were not significantly different from each other. The results demonstrated the high potential of the two isolates (PPRC51 and PPRC2) as microbial biocontrol agents. However, field evaluation of the isolates should be performed for their development into a mycopesticide against P. interrupta.

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Sorghum chafer, Pachnoda interrupta (Olivier), is the most serious pest of sorghum in Ethiopia destroying the entire fields at the milk stage and causing up to 100% yield loss. Current control methods entirely depend on direct spraying and baiting with insecticides which does not provide long lasting control. Efficient biological control agents such as entomopathogenic fungi that can control the pest in the breeding sites need to be developed. Traps equipped with auto-inoculation devices are important alternative methods to spread entomopathogens into insect pest populations. Field studies on fungal auto-inoculation trap development from locally available materials conducted over three feeding and two mating seasons of P. interrupta resulted in two efficient auto-inoculation traps (AIT1 and AIT2) baited with a five compounds blend lure which were not significantly different in catch performance with the standard Japanese beetle trap. Two selected virulent isolates of Metarhizium anisopliae (PPRC51 and PPRC2) were tested for field efficacy using these two designs of locally affordable auto-inoculation traps loaded with 1gm of dry conidia. Using AIT1, PPRC51 and PPRC2 induced 41% and 40% field mortality respectively, on P. interrupta adults under high temperature and low relative humidity conditions, while highest field viability of the two isolates five days after application was 36 % and 40 % for PPRC51 and PPRC2, respectively. Based on the catch performance, field efficacy and viability data observed, the two AIT's are recommended for further development to be used with PPRC51 and PPRC2 for augmentation biological control in the pest's natural habitat as a component of integrated pest management against P. interrupta.