Biologieal characterics of the pathogen of soybean pod anthracnose,Colletorichum truncatum

The effects of illumination,temperature,pH value,humidity, carbon source and nitrogen source on the mycelial growth,sporulation and conidial germination of Colletotrichum truncatum was primarily studied.The results showed that illumination have no much effect on the mycelial growth,sporulation and conidial germination of the fungi.Its mycelium grew between 15-35℃,and optimum temperature was at 30℃.It grew between pH 3-12,and optimum pH volue was between pH 5-7.The conidia germinated between 15-30℃,and optimum was at 25℃,It germinate between pH 3-10,and optimum was between 6-8.The lethal temperature of conidia and mycelium was at 56℃ and 60℃,respectively.The conidia could not germinate when the relative humidity below 97%.The pathogen could use a variety of carbohydrates and nitrogen sources,but for the mycelial growth,the optimum carbon source was sucrose,and the optimum nitrogen source was yeast.For the sporulation,the optimum carbon source was maltose,and the optimum nitrogen source was yeast.