Preparation And Application Effect Of Low-temperature Degradable Bacteria Compound Agent Of Corn Straw

The low temperature in northeast China is long,and the straw return is difficult to degrade,which has become a bottleneck problem for the sustainable development of straw return in the northeast region.Based on this,this paper collects the soil at the degraded straw from the cornfield in various regions of Jilin Province,separates and screens the straw degrading bacteria under low temperature conditions of 15 °C,prepares them into a composite bacterium,and analyzes the application effect of the compound bacterial agent and the impact on the microbial colonies in the soil of the returned soil,and the main conclusions are as follows:1.23 strains with strong cellulose degradation ability were screened out by low temperature culture,including 15 fungi and 8 bacteria.Among them,Z6,Z14,X20,Z18,Z17 strains have higher enzyme-producing ability,X20 strain has the highest degradation rate of liquid fermentation straw,Z14 strain has the highest solid-state fermentation straw degradation rate,and fungi Z17,Z6,Z14 strains have the highest hyphae drying rate.The larger the weight,the faster the growth rate of bacteria X20,X8 and X13.2.Screening and compounding of degrading bacteria,JA compound bacteria agent has the highest comprehensive enzyme production ability,its cellulase and laccase production ability is the strongest,JB compound bacteria agent has the strongest xylanase production ability,and JC compound bacteria agent has the strongest ability to produce xylanase.The ability to produce filter paper enzymes is the strongest.JB and JA composite inoculants had higher degradation rates of liquid fermentation straws,and JA composite inoculants had the highest degradation rate of solid-state fermentation straws.Molecular biology identification was carried out on the constituent strains of the JA compound inoculum,and the constituent strains were: Trichoderma viride,A.3.Compared with other inoculants,the JA compound inoculants have the highest degradation rate of straw,straw cellulose,hemicellulose and lignin,and the degradation rate of straw returning to the field is 46.57% in 40 days.In addition,the application of JA compound bacterial agent can significantly enhance the soil fertility of straw degradation,and its degradation products are not toxic to plants.4.Compared with the application of other inoculants to degrade soil microbial colonies,the application of JA compound inoculants,Sordariomycetes,Lasiosphaeriaceae,Sordariales,Lasiosphaeriaceae sp.species,Hypocreales fam Incertae sedis,Rhodanobacteraceae and The abundance of Rhodanobacter was significantly increased,which decreased the microbial diversity of straw returning soil.Spearman analysis showed that PH was positively correlated with the abundance of fungal genera,EC,OM,AN,AP,AK were negatively correlated with the abundance of fungal genera;PH,EC,OM,AN,AP,AK were positively correlated with the abundance of bacterial genera related.The development of degrading bacteria with strong straw degradation ability under low temperature conditions is a favorable measure to solve the difficult problem of straw returning to the field in low temperature areas such as Northeast China.The corn stalk low-temperature degrading bacteria composite bacterial agent JA developed in this paper has a degradation rate of 46.57% after returning the straw to the field for 40 days,which is significantly higher than that of the commonly used commercially available bacteria.excellent fungicide.