Effect Of Microbial Fertilizer On Microenvironment Of Corn Rhizosphere

In China,Corn is one of the most important grain crops,occupies an important position in the economic development of agriculture.In recent years,with the extensive use of chemical fertilizers,a series of soil environmental problems have arisen.Soil microbes are an important part of the soil ecosystem and play an important role in ecosystem functions such as soil carbon and nitrogen cycling and transformation.Therefore,studying the effects of microbial fertilizers on soil microflora is of great significance for improving soil environment,improving soil fertility levels and regulating ecosystems.In this study,the effects of five different fertilization treatments on rhizosphere soil enzyme activities,soil nutrient and soil bacterial community structure and function during maize growth were investigated.The result of research shows that:(1)The soil enzyme activity showed almost the same change during the growth period of maize.The peaks of soil invertase and urease activity appeared at jointing stage,and soil catalase had the highest activity at maturity;under the application and application methods,The application of compound microbial fertilizer could increase the activity of catalase,which was 6.3%~9.0% and 4.0%~10.5% higher than that of the control at different times.The addition of Bacillus amyloliquefaciens microbial fertilizer increased the activity of invertase and urease.In the different periods,the invertase activity was 20.7%~68.0% and 18.6%~37.4% higher than the control.The urease activity in the different periods was 21.8%~30.4% and 4.6%~14.4% higher than the control.The two fertilization methods show that the application can improve the comprehensive utilization of fertilizer and facilitate the full absorption of crops.In summary,the combination of inorganic fertilizer and microbial fertilizer can improve the rhizosphere soil environment of maize and increase the activities of invertase,urease and catalase in soil.(2)The application of microbial fertilizer has different effects on soil nutrient: during the growth period of maize,soil organic matter and total nitrogen content increased first and then decreased with time,soil available phosphorus and available potassium content with time The change showed a trend of decreasing first and then increasing,while the variation of soil total phosphorus and total potassium content during the growth period of maize was not affected by fertilization treatment.Compared with single application of chemical fertilizer,soil organic matter content increased by 9.4%~20.3% during the growth period of maize,soil total nitrogen content increased by 9.8%~40.8%,soil total phosphorus content increased by 12.4%~38.6%,soil quick-acting The potassium content increased by 10.5%~82.1%,and the soil available phosphorus content increased by 4.6%~87.4%.Therefore,microbial fertilizer can improve the content of soil organic matter,total nitrogen,total phosphorus,available phosphorus and available potassium in varying degrees,but has no obvious effect on the total potassium content of soil.(3)The full-length 16 S r RNA sequence of maize rhizosphere bacteria was determined by Illumina Mi Seq high-throughput sequencing technology,so as to analyze the structure and diversity of corn rhizosphere soil bacterial community with different microbial fertilizers.After sequencing the quality data,a total of 86249 effective sequences and 5362 OUT numbers were obtained.The results of diversity analysis showed that the abundance and diversity of Bacillus subtilis treatment(KC)were the highest,and the abundance and diversity of composite bacterial treatment(FH)were the lowest.The analysis of soil bacterial community composition found that the dominant bacteria in the five soil samples were Proteobacteria Acidobacteria Actinobacteria and Gemmatimonadetes.The dominant bacteria species were Aciditerrimonas ferrireducens JCM 15389,Gemmatimonas aurantiaca and Pyrinomonas methylaliphatogenes.KC treatment reduced the proportion of Proteobacteria,Acidobacteria and Gemmatimonadetes,and increased the proportion of Actinobacteria;FH treatment resulted in a decrease in the proportion of Proteobacteria and Actinobacteria,and an increase in the proportion of Acidobacteria and Gemmatimonadetes.The redundancy analysis showed that soil organic matter,total phosphorus and available phosphorus were the main factors affecting the microbial community structure in maize rhizosphere.In summary,the combination of inorganic fertilizer and microbial fertilizer can improve the rhizosphere soil environment,increase soil enzyme activity,and increase soil organic matter and soil nutrient content.At the same time,the application of microbial fertilizer can affect the structure and diversity of soil bacterial community,promote the colonization of dominant rhizosphere bacteria,and accelerate the growth and development of plants.Therefore,the results of this study can provide a theoretical basis for the microbial fertilizer to stabilize the yield of corn and increase the efficiency of fertilizer.