| Cortex phellodendri is the dry skin of P.chinense Schneid.and P.amarense rupr.of Phellodendron ruper. Genus, rutaceae Faculty,which is one of the most famous mainland medicinal materials in Si-chuan province. Phellodendron Anthracnose was a disease caused by Colletotrichum gloeosporioides,which usually occur in area of Cortex phellodendri planting. This dissertation studied the isolation and identification, biological characteristics and indoor fungicides screening of the pathogen. The main results are as follows:1. Isolation and identification of the pathogenOne fungal colony was isolated from the diseased plant leaves. We did traditional morphological identification and bio-molecular identification on pathogen. Based on the results of morphological characteristics, cultural feature, and sequence analysis on rDNA-ITS, we made the decision that the pathogen of Phellodendron Anthracnose was Colletotrichum gloeosporioides. Acervulus with brown bristles in size of 2.2-3.2μm wide×70-112μm long, which scattered or gathered under the host's epiderm at the beginning, and broke through the host's epiderm after. Conidiophore with septum, and colorless. Sporulate cell, colorless, cylindric in shape. Conidia, colorless, single spore, short cylindric in shape, sometimes had 1-2 oil ball, size range should be extended to between 4-6μm wide×12-18.5μm long. 2. Biological characteristics of the pathogenThis paper studied the temperature, relative humidity, time, pH, light, and nutritions' influences on growth and sporulating of hypha, and spores'germination. Finally, we got the best condition of growth and sporulating of hypha, and spores'germination.The results showed that:the temperature range for hypha growth was 10-35℃, the optimum was 30℃. And for sporulating, the temperature range was 15-30℃, the optimum was 25℃. The pathogen could grow better on PDA,10%,20% leaves'juice +PDA than the others. The best medium for sporulating was PDA. pH value range for hypha's growth and sporulate was 5-11, the optimum for hypha's growth was 5-8, and the optimum for sporulating was 5-7. In the utilization of carbon sources, sucrose and xylose were the best for hypha's growth, starch was the best for sporulating, and the most suitable nitrogen source was peptone. Light almost had no influence on hypha's growth, but good for sopeulating.Conidial germination had a low percentage in sterile deionized water, sugar was good for conidial germination, and 1-2% host juice could obviously stimulate conidial germination. Conidia germinated at 15 to 35℃, and with the optimum between 25 and 35℃. Conidia could germinate at 4 hour under the best condition. Conidia germination required high relative humidity, conidia would begin to germinate just only the relative humidity up to.100%. The optimum pH value for conidia germination was 5 to 7. Conidiophore was sensitive to light. Total darkness was good for germination and growth of germ tube. In addition, the lethal temperature of hypha and conidiophore was 49℃and 54℃, respectively.3. The fungicides screening in laboratoryFour fungicides (carbendazim, diniconazole, triadimefon, imazalil)were tested; in laboratory to determine the effect on the hypha growth and germination of conidia. The results showed that carbendazim was the most effective one, imazalil was the second, tridimefon was inferior to imazalil, and diniconazole almost had no effect.
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