一株假单胞菌的分离鉴定及其在青海地区堆肥中的应用潜力

Isolation and identification of a Pseudomonas strain and its application potential in rape straw composting in Qinghai,China

为了筛选出适用于青海地区油菜秸秆纤维素降解的菌株,提高当地油菜秸秆堆肥的效果,从青海省西宁市北山土壤中分离得到1株纤维素降解菌,经鉴定为假单胞菌属(Pseudomonas sp.),其羧甲基纤维素(CMC)酶活为25.35 U·mL^(-1),外切-β-葡聚糖酶活为22.33 U·mL^(-1),滤纸酶活为20.58 U·mL^(-1)。将该菌株制成微生物液体菌剂,按10 mL·kg^(-1)的比例接种于堆肥试验中作为试验组,与不添加菌剂的对照组相比,试验组堆体升温快,高温持续时间长。堆肥结束时,试验组堆肥的pH值和电导率均在合理范围内,种子发芽指数为90%,达到腐熟标准,堆体含水率下降至30%以下,全氮含量为1.39%,有机质含量为49.16%。结果说明,筛选出的菌株可应用于青海地区的油菜秸秆堆肥,能够加快堆肥腐熟,并提高堆肥质量。

In order to accelerate the cellulose degradation of rape straw and improve the composting quality in Qinghai,China,a cellulose degrading strain was isolated from the soil of Beishan,Xining City,Qinghai Province,and was classified as the genus of Pseudomonas sp.Its carboxymethyl cellulase(CMC)activity,exo-β-glucanases activity,and filter paper activity(FPA)were 25.35,22.33,20.58 U·mL^(-1),respectively.The strain was made into a liquid microbial inoculum and applied in a composting test at the rate of 10 mL·kg^(-1) as the experiment group.Compared with the control group without application of microbial inoculum,the stack of the experiment group heated up quickly and the high temperature lasted longer.At the end of composting,the pH value and electrical conductivity of the experiment group were within a reasonable range,the seed germination index of the experiment group was 90%,which met the maturity standard,the moisture content of the stack dropped to 30%below,and the contents of total nitrogen and organic matter were 1.39%and 49.16%,respectively.Therefore,the isolated strain could be used in the rape straw composting,which could both accelerate the rate and improve the quality of composting in Qinghai.