Alginate pellets were prepared from wet fermentor biomass of 11 isolates ofTrichodermaspp. andGliocladium virens, with wheat bran as a food base carrier. Pellets with eight of the isolates reduced survival (34‐78) ofRhizoctonia solaniin infested beet seed in soil. Pellets containing aT. harzianumisolate (Th‐58) and aT. hamatumisolate (TRI‐4) were the most effective. All isolates significantly reduced growth of the pathogen from infested beet seed into natural soil. Populations of isolates proliferated in soil to 106−1011colony‐forming units/g (cfu) from propagules within the pellets. Pellets with TRI‐4 reduced pathogen survival and growth (>70) in six different soils and were effective against sixR. solaniisolates in a natural loamy sand. Survival ofR. solaniin infested beet seed was not reduced when TRI‐4 pellets were added to soil 1‐6 weeks before the pathogen; however, saprophytic growth was prevented. Small amounts of biomass (3.0–7.5 g wet weight) in pellets were as effective as a large amount (300 g) in suppressing the pathogen. The storage of pellets for more than 6 weeks at 5 or 25C reduced their effectiveness againstR. solani.Pellets prepared with four and three of the 11 isolates prevented damping‐off of cotton and sugar beet in the green
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