通过筛选高效的秸秆纤维素降解菌，为进一步资源化利用农作物秸秆提供优质的微生物资源。采集奶牛粪样品，通过纤维素平板刚果红染色法初筛及发酵液纤维素酶和木聚糖酶活性测定法复筛菌种，探究选出菌株对秸秆的降解能力。结果表明，筛选获得9株产纤维素酶的菌株，其中菌株TX1的透明圈与菌落直径比值最大，为1.729。菌株TX7的纤维素酶活力和木聚糖酶活力最强，CMC-Na酶(CX)活力为0.224 7 U/mL，滤纸酶(FPA)活力为0.296 0 U/mL，木聚糖酶活力为8.84 U/mL。菌株TX3对小麦秸秆半纤维素和纤维素的降解能力最强，每1.000 g小麦秸秆的纤维素、半纤维素质量分别为0.185、0.190 g；菌株TX7对小麦秸秆木质素的降解能力最强，每1.000 g小麦秸秆的木质素质量只有0.037 g。由此可见，菌株TX3、TX7具有进一步研发成高效降解秸秆微生物菌剂的潜力，为秸秆纤维素的转化利用提供了优质的菌种资源。

In order to screen for efficient cellulose degrading bacteria for straw, so as to provide high-quality microbial resources for the further resource utilization of crop straw, dairy cow dung samples were collected, and the strains were initially screened by cellulose plate Congo red staining and rescreened by cellulase and xylanase activity measurement in fermentation broth to explore the degradation capacity of the selected strains on straw. Results showed that 9 strains of cellulase-producing bacteria were obtained, among which strain TX1 exhibited the largest hyaline circle to colony diameter ratio of 1.729. Strain TX7 had the strongest cellulase and xylanase activity, with a CMC-Na enzyme(CX) activity of 0.224 7 U/mL, a filter paper enzyme(FPA) activity of 0.296 0 U/mL, and a xylanase activity of 8.84 U/mL. Strain TX3 showed the strongest degradation capacity for hemicellulose and cellulose in wheat straw, with cellulose and hemicellulose masses of 0.185 g and 0.190 g, respectively, per 1.000 g of wheat straw. Strain TX7 exhibited the strongest degradation capacity for lignin in wheat straw, with a lignin mass of only 0.037 g per 1.000 g of wheat straw. Thus, strains TX3 and TX7 have the potential for further development into efficient strawdegrading microbial agents, providing high-quality microbial resources for the conversion and utilization of straw cellulose.

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中央引导地方科技发展资金项目(23YQA0323)；甘肃省现代农业科技支撑体系区域创新中心重点科技项目(2023GAAS07)；甘肃省农业科学院科技成果转化项目(2024GAAS-CGZH04)。