1College of Horticulture and Plant Protection，Inner Mongolia Agriculture University，Hohhot 010020，Inner Mongolia，China；2Civilization Practice Guidance Center in the New Era in Ulanqab of Inner Mongolia，Ulanqab 012000，Inner Mongolia，China
摘要 为快速降解马铃薯秸秆，从马铃薯田取土样分离秸秆降解菌并使用刚果红染色法进行初筛，得到1 株菌株，命名为WXB10，其在28 ℃、180 r · min-1 条件下发酵35 d 时马铃薯秸秆降解率可达57.73%。菌株WXB10 可产生半纤维素酶、内切-β-1，4- 葡聚糖酶、外切-β-1，4- 葡聚糖酶和β- 葡萄糖苷酶，发酵5 d 时，半纤维素酶活性最高，为32.17 U ·mL-1；发酵3 d 时，内切-β-1，4- 葡聚糖酶活性最高，为238.75 U · mL-1；外切-β-1，4- 葡聚糖酶和β- 葡萄糖苷酶活性均在发酵4 d 时达到最大值，分别为478.48 U · mL-1 和4.82 U · mL-1。结合形态学观察、生理生化试验和分子生物学鉴定结果，菌株WXB10 被鉴定为贝莱斯芽孢杆菌（Bacillus velezensis），具有较高的纤维素酶活性，能快速降解马铃薯秸秆。
Abstract：In order to rapidly degradate potato straw，this experiment took soil samples from potato fields，separated straw-degrading bacteria，carried out preliminary sceening by congo red staining method，and obtained one strain，named WXB10．Under the fermentation condition of 28 ℃ and 180 r · min-1 for 35 days，potato straw degradation rate of this strain could reach 57.73%．The strain WXB10 could produce hemicellulase，endonuclease-β-1，4-glucanase，extraneous-β-1，4-glucanase and β-glucosidase．The hemicellulase activity was the highest 32.17 U · mL-1 after being fermented for 5 days．The endonuclease-β-1，4-glucanase activity was the highest 238.75 U · mL-1 after being fermented for 3 days．Both extraneous-β-1，4-glucanase and β-glucosidase activities reached the maximum value after being fermented for 4 days，reaching 478.48 U · mL-1 and 4.82 U · mL-1，respectively．Combining the results of morphological observation，physiological and biochemical experiment，and molecular biological identification，strain WXB10 was identified as Bacillus velezensis，possessing higher cellulase activity and being able to rapidly degrade potato straw．
