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Black root rot of faba bean is one of the most destructive diseases that causes up to 100% yield loss on farmers’ fields under severe conditions. As use of chemical fungicides for control of the disease is neither efficient nor economical, alternative options such as biological control need to be exploited. The antagonistic fungus <em>Trichoderma harzianum</em> was used as seed dressing or soil application treatment in combination with three varieties <em>viz</em>. Kasa (susceptible), Wolki (moderately resistant) and Wayu (resistant) in two consecutive cropping seasons in a sick plot. Each variety was sown with and without <em>T. harzianum</em>. There were a total of six treatments. The experimental design was randomized complete block design with three replications in a 2 x 3 factorial arrangement. Results showed that in the first year highly significant variations in the percentage of dead plants at harvesting stage were observed only due to varietal differences for soil treatment (<em>P</em> = 0.0001) and seed dressing (<em>P</em>&lt; 0.0001) respectively. Percentage of dead plants of variety wayu was 26.1% and 30.8% in soil application and seed dressing treatments respectively. Similarly, 92.1% and 95.2% dead plants were observed for the susceptible variety Kassa in soil application and seed dressing treatments respectively. In the second year there was a significant interaction between varieties and <em>Trichoderma</em> treatments (<em>P</em>=0.0047, F=8.66, df= 2) with variety Wayu showing the least percentage of dead plants (56.58%) significantly differing from Kassa (93.86%) and Wolki (77.08%) in the soil treatments. It is concluded that use of <em>T. harzianum</em> in combination with a resistant variety such as Wayu is effective to reduce the incidence of faba bean root rot caused by <em>Fusarium solani</em>. Future research should focus on studying the effects of combining different <em>Trichoderma</em> spp. on the disease as integrated with resistant varieties.

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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