一种降解秸秆的丝状真菌的分离和定性方法

建立了一种新的简单的分离秸秆降解丝状真菌的方法,用此方法从东北寒地黑土中分离出真菌56株,其中丝状真菌46株。这种分离方法简述为：先用土壤或者堆肥浸渍秸秆至接近腐烂,再用酒精对接近腐烂秸秆进行表面灭菌,最后用土豆葡萄糖琼脂培养基培养并分离秸秆中微生物,这样分离的微生物大多为产丝真菌。用添加或者不添加硝酸铵、酵母粉和黑土浸液等辅助物的秸秆粉制成不同培养基,这些培养基用来比较其对分离的微生物的生长的影响。结果表明,同一微生物在不同培养基中生长区别很小,同一培养基不同微生物生长区别较大。选择了只含秸秆粉而不添加辅助物的培养基作为微生物是否降解秸秆的定性培养基,对分离的56株真菌以水稻、大豆和玉米3种秸秆进行降解定性鉴定,结果显示：该方法筛选的46株丝状真菌都能降解3种供试秸秆。

A Method for Isolate and Determine Filamentous Fungi That Could Degrade Stalks

A new simple method to isolate filamentous fungi that could degrade stalks were built. Fifty-six strains of fungi include 46 strains of filamentous fungi were isolated from the black soil in the northeast frigid zone in China by the method. The isolation method could be summarized as ： Stalks were nearly rotten after being covered with soil or compost suspension for a few days, ethanol were used to disinfect the surface of the stalks, the culture medium（Potato Dextrose Agar,PDA）were used to isolate the microorganisms in the stalks, most of the microorganisms isolated by the method are filamentous fungi. Three dry stalks include straw, soybean stalk and corn stalk are collected to be pulverized to made stalk powder. Stalk powder added with different matter（NH4NO3, yeast abstract, black soil solution）or not were recruited to made solid culture media to compare the growth of the microorganisms isolated. Results showed that there are little differences between the growth of the same strain on different media but varified differences between the growth of the different strains on the same medium. The simple medium made by stalk powder without any of the adding matters were chosen to determine whether the three stalks were degraded by the 56 strains of fungi. Results showed that all of the 46 strains of filamentous fungi isolated by the method could degrade the three stalks.