Screening for Antagonistic Yeast against Tomato Early Blight

120 yeasts were isolated from the surface epiphytes of several fruits. 11 of them exhibited inhibitory activity to Alternaria solani by the method of dish screening (in vitro). The tests of equivalent volume mix of each yeast isolate and Alternaria solani suggested 7 of 11 yeast isolates at the three concentration of 10~6,10~7 and 10~8CFU·ml~(-1) can totally restrain the growth of Alternaria solani at the three concentration of 10~5,10~4 and 10~3spores·ml~(-1). The yeast isolate L-1-6 was found to be highly antagonistic to Alternaria solani on three varieties tomato by test in vivo and the average percent controlling amounted to 77.78%.