关键词: 马蹄金, 褐色叶斑病, 马蹄金核腔菌, 生物学特性

Abstract: For the grow th and ascospore formation of Pyrenophora dichondrae sp. nov. , the best medium was PDA, the optimum temperature was 25~28℃ and the optimum pH was 5~7. Complete darkness promoted ascospore formation and complete illumination promoted hypha growth. The pathogen could make use of many kinds of carbohydrates, and dextrose seemed to be the best C source, while malt sugar the poorest. Calcium nitrate was the best N source, while ammonium chloride was the poorest. For ascospore germination of the pathogen, the optimum temperature and relative humidity (RH) were 20~28℃ and 90%~100% respectively. The optimum pH for ascospore germination was in the range of 6~8. For ascospore germination of the pathogen, the best C source was dextrose and N source was sodium nitrate. The thermal death point of the ascospore was 49℃.

Key words: Dichondra repens, brown leaf blight, Pyrenophora dichondrae sp. nov., biological characteristics