关键词: 虎杖药渣, 复合微生物菌剂, 降解, 腐熟效果, 资源化利用, 堆肥

Abstract: To screen for efficient degrading functional microorganisms and construct a compound microbial agent suitable for the resource utilization of Polygonum cuspidatum residues，so as to solve the problems including difficult degradation of Polygonum cuspidatum residues in the natural environment and the resulting environmental pollution and resource waste，compost pile，soil from Polygonum cuspidatum planting fields，decomposed straw，decomposed Polygonum cuspidatum，and the laboratory strain collection were used as the sources for strain screening. Functional microorganisms with high cellulase and protease production were directionally screened by clear⁃zone tests，filter⁃paper disintegration tests，and residue degradation tests，and the enzyme activities of the strains were determined.The strains were identified by molecular biology techniques，and antagonism tests were conducted to evaluate the compatibility among the strains. Solid microbial agents were prepared from the selected strains by solid⁃state fermentation. The formulation of the microbial agent was optimized by the U₆*（66）uniform design method，and the maturation effect was evaluated based on composting trials，with the maximum composting temperature，duration of the thermophilic phase，seed germination index，and T value（final C/N ratio divided by initial C/N ratio） used as the evaluation indicators to determine the optimal formulation of the compound microbial agent. The strain screening results showed that three fungal strains（X1，X2，and TR） with high cellulase production，capable of efficiently degrading Polygonum cuspidatum residues and ten bacterial strains （D9，D11，D12，F5.1，F5.2，F5.3，F7.3，JD7.1，Z7.1，and BS）with high protease production were obtained. Among them，Trichoderma reesei TR and Bacillus subtilis BS were previously obtained and preserved in the laboratory strain collection.Molecular identification showed that X1 was Aspergillus niger，X2 was Trichoderma longibrachiatum，D9，F7.3，and JD7.1 were Bacillus amyloliquefaciens，D11 was Bacillus velezensis，F5.1，D12，and Z7.1 were Bacillus subtilis，and F5.2 and F5.3 were Priestia megaterium. Based on the enzyme activities and identification results，six superior strains （X1，X2，TR，D9，D11，and F5. 1） with strong functional complementarity and high enzyme activities were selected.The antagonism test results showed no obvious antagonism among the six strains，which could coexist well and meet the compatibility requirements of the compound microbial agent. The composting results showed that the optimal formulation of the compound microbial agent was TR∶X1∶X2∶D9∶D11∶F5. 1=5∶3∶1∶6∶4∶2. This formulation was superior to the other treatment groups in effectively increasing the peak composting temperature，prolonging the thermophilic phase，improving the seed germination index，promoting organic matter degradation，and decreasing the T value of the compost. The organic matter content，total nutrient content，moisture content，pH value，and seed germination index of the mature compost were 41.38%，6.95%，29.95%，8.12，and 93.35%，respectively. In conclusion，multiple efficient degrading strains for Polygonum cuspidatum residues were successfully screened，and a compound microbial agent with good compatibility and excellent degradation performance was constructed，with the optimal formulation of TR∶X1∶X2∶D9∶D11∶F5. 1=5∶3∶1∶6∶4∶2.

Key words: Polygonum cuspidatum residue, Compound microbial agent, Degradation, Compost maturity effect, Resource utilization, Composting