Abstract: The biological characteristics of Stemphylium lycopersici were studied and the preliminary screening of fungicides was conducted in the lab. Results showed that HZ2111 was able to grow at pH between 4.0 to 9.0， and 25 ℃ under 12 h light/12 h dark alternate illumination was benefit to colony growth; starch and yeast extract were the best carbon and nitrogen source for mycelia with linear growth rates of 3.17 and 9.04 mm·d-1， respectively， while galactose and ammonium sulfate showed the least linear growth rates of 0.78 and 0.36 mm·d-1， respectively. Studies on the effects of the fungicides on mycelial growth of HZ2111 revealed that 14 fungicides were all effective to HZ2111， and 500 g·L-1 fluazinam and 50% fludioxonil were the most effective inhibitors with EC50 as 0.000 1 and 0.000 2 μg·mL-1， respectively. Studies on the sensitivity tests of the fungicides on spore germination of HZ2111 showed that 12.5% tetraconazole， 70% phosethy\|Al·mancozeb， 75% tebuconazole·azoxystrobin， 30% carbendazim·thiram and 75% trifloxystrobin·tebuconazole were all effective， and tetraconazole was the most effective one with MIC less than 0.05 μg·mL-1.

Key words: Stemphylium lycopersici, biological characteristics, fungicides