抄録
We developed a simple method to test the Quinone outside inhibitors (QoI) sensitivity of Pestalotiopsis longiseta, the causal fungus of tea gray blight. Diseased tea leaves were incubated under humid conditions for 2-4 days to form conidia. Healthy mature tea leaves were boiled in water for 5-10 minutes, immersed briefly in a 200-fold dilution of azoxystrobin 20% flowable, and placed on wet facial tissues in an air-tight container. Conidia on lesions were transferred to wet absorbent cotton and inoculated onto the boiled tea leaves. After 3 days incubation at room temperature, QoI-resistant isolates grew equally well on both fungicide-treated and non-treated leaves. In contrast, QoI-sensitive isolates did not grow on the fungicide-treated leaves. Both highly and moderately resistant isolates were identified as resistant in this test. Pestalotiopsis longiseta was distinguishable from unwanted fungi based on the formation of black conidial masses after 7-10 days incubation under diffused daylight.
