水稻秸秆腐熟菌株筛选及其复合菌系的构建OA

To address the issues of prolonged decomposition time and poor decomposition effects associated with using single strains or composite microbial systems for straw treatment,strains with straw-degrading capabilities were screened based on the enzymatic activities of cellulase,laccase,xylanase,and lignin peroxidase as indicators.The selected strains were identified and antagonism tests were conducted,then their decomposition capabilities were determined.A total of 85 strains exhibiting enzymatic activities related to straw degradation were screened.Three straw-decomposing strains with no mutual antagonism and relatively high enzymatic activities were selected.Through molecular biological identification,all three were confirmed to belong to Bacillus genus.The results indicated that the cellulase and xylanase activities of strain L4 reached 0.235 U/mL and 1.335 U/mL,respectively.The laccase activity of strain L6 was measured at 0.711 U/mL,and the lignin peroxidase activity of strain X6 reached 4.301 U/mL.The decomposition experiment results demonstrated that the cellulase activity within the straw stack was increased by 53.47％,xylanase activity by 52.72％,laccase activity by 46.46％,and lignin peroxidase activity by 68.56％after 40 d compared with natural decomposition.The straw weight loss rate was increased by 16.06％,and the cellulose degradation rate was increased by 23.67％.When the decomposed straw was used as compost,the wheat seed germination rate was increased by 16％.The composite microbial formulation prepared from the screened strains and added to straw for decomposition was found to enhance the enzymatic activities within the straw stack,effectively promote straw decomposition,and improve crop growth.