Abstract:

In order to clear the toxicity of the mixture of validamycin 5% WP and Bacillus subtilis (200 hundreds million spores per gram) to Rhizoctonia cerealis; the toxicity test was determined in laboratory by mycelium growth rate method. According to Wadley method, the synergistic activity was evaluated, and pot experiment of different ratio was studied. Results showed that coefficient of synergism was the highest and synergistic activity was the strongest when the ratio of validamycin 5% WP and Bacillus subtilis (200 hundreds million spores per gram) was 1:1. It’s preventing effect were 78.8%, 77.3%, 75.1% when concentration was 500, 125, 250 mg/L respectively, higher than carbendazim 50% WP (167 mg/L) and validamycin 5% WP (500 mg/L). The preventing effect and cure effect were evident. The mixture of validamycin 5% WP and Bacillus subtilis (200 hundreds million spores per gram) could taken as an ideal fungicides to Rhizoctonia cerealis.