Abstract: The biological characteristics and fungicide sensitivity of Kabatiella microsticta causing
daylily leaf streak were studied. The results showed that the suitable temperature for mycelium growth and
spore production of the pathogen was from 25 ℃ to 30 ℃，and 28 ℃ was the optimum. The optimal media
for mycelium growth were PDA，PSA and CA，but V8 juice was the best for spore production. D（+）-
maltobiose and L-leucine were optimal for mycelium growth and spore production. The suitable pH for
mycelium growth was 5 to 9，and 7 was optimum for spore production. Light could promote spore
production and had no effect on mycelium growth. The lethal temperature of conidia was 49 ℃，10 min.
The sensitivity of K. microsticta to twelve fungicides was detected by mycelium growth rate method. The
results showed that the pathogen was more sensitive to carbendazim，thiophanate-methyl，penconazole，
propiconazole，flusilazole，trifloxystrobin·tebuconazole，myclobutanil，EC50 < 1.0 mg · L^-1，EC90 < 5.0
mg · L^-1. This study will lay theoretical foundation for occurrence law and control of the disease.

Key words: Hemerocallis, daylily leaf streak, biological characteristics, laboratory toxicity