Effects Of Biostimulating Factors On Soybean Rhizosphere Soil Microorganism And Its Yield

Field experiments were conducted to study the effect of biostimulating hormone(diphenyl urea sulphonate)on microbial community and its physicochemical properties in soybean rhizosphere soil,and then to explore the role of biostimulating hormone in optimizing soybean symbiotic nitrogen fixation environment,improving soybean physiological index and improving soybean quality function.The research methods of this article include: 1.Soaking seedlings of kidney bean No.78 with Chinese rhizobium rhizobium or different concentrations of biostimulating hormone,including five experimental groups S1,S2,S3,S4,and S5,and a blank CK control group.Soybean rhizosphere soil was collected after sowing at the soybean flowering stage,and soil rhizosphere microbiological DNA extraction was performed by comparative modified SDS method,TSAI method,biochemical kit kit and Mobile kit method.Finally,the best extraction method was selected.2.Specific amplification of the 16 S V3 region of the target segment was performed.The amplified product was sequenced using a Roche FLS sequencer(Roch GS FLX sequencer).After data processing,rhizosphere soil microbial community diversity analysis,Shannon-Wiener curve analysis of rhizospheric soil microbial communities,rhizospheric soil microbial community structure analysis,cluster analysis,and structural analysis of some bacteria at genus level were performed.3.The physiological indexes such as root nodule number,root vigor,plant dry weight,nitrogenase activity and bean hemoglobin content were measured for each group and the experimental data were analyzed.4.The AA3 continuous flow analyzer was tested and validated,and the protein content of the soybean kernels in each of the previous experimental designs was determined.The results obtained by the above research methods are: 1.Roughly extract the soil rhizosphere microbial total DNA by two hand-carried and two-kit methods and compare the extraction efficiency and DNA purity of these methods;then the target bacteria 16 S V3 region primer(Lane et al.,1991)was used for PCR amplification and verified by agarose gel electrophoresis;the DNA band extracted by the Mobile kit was strong and reproducible.2.Compared with the CK group in the five experimental groups,the values of Shannon and Chao1 decreased in the experimental group.Comparing S2,S3,S4 and S5 with CK,the relative contents of Proteobacteria,Actinomyces and Bacteroidetes were found to be increased;the relative contents of Acidobacteria and Streptococci were reduced.The experiment also found that at the genera level,some functional strains that are beneficial to the growth of soybeans and promote nitrogen fixation have an increasing trend.Through statistics on the number of root nodule of the plant,the number of root nodules in soybean plants showed trends of S5>S4>S3>S2>S1>CK.The activity of roots in S1,S4,and S5 was higher in the experimental group at the seedling stage,and the root activity of the soybean plants was weakened except for the experimental groups S2 and S3.,S4 and S5 generally remain at their original level.According to the statistics of dry weight of the plants,the dry weight of the experimental group was increased compared with the control CK.At the seedling stage,there was no significant difference between the experimental groups,but it can be seen that with the advancement of the growth period,the biostimulating hormone The effect gradually showed,and the dry weight of plants showed S5>S3>S4>S2>S1>CK.Through the determination of root nodule nitrogenase activity,the activities of S2,S3,S4 and S5 groups were relatively high,and finally showed as S5>S3>S2>S4>S1>CK.The main functional constituent of nitrogenase is Bean Hemoglobin.Therefore,the effect of applying different concentrations of biostimulating hormone hormone on the content of Bean Hemoglobin is basically consistent with the effect of nitrogenase activity,which is represented by S5>S3>S2>S4>S1>CK.4.Calculate the soybean protein content by measuring the total nitrogen content of soybeans with the AA3 continuous flow analyzer.We can conclude that the soybean protein content shows S5>S4>S3>S2>S1>CK.Finally,the comparative analysis of the experimental data obtained can be obtained:1.Mobile's BIO-101 DNA extraction kit is highly purified and has low levels of humic acid in the extracted soil DNA,and is specifically amplified in the 16 s V3 region after detection by agarose gel electrophoresis.With the strongest signal,good repeatability.Therefore,the mobile kit was selected to extract the soil rhizosphere microbial DNA for follow-up experiments.2.The application of biostimulating hormone will reduce the microbial diversity of soybean rhizosphere soil;it can promote the growth of rhizobia and increase the content of rhizobia in rhizosphere soil microorganisms;at the same time,biostimulating hormone can also increase the functional bacteria in the rhizosphere soil microorganisms,it not only promotes nitrogen fixation in soybeans,but also promotes the growth and development of soybeans.3.Biostimulating hormone can increase the number of root nodules and dry weight of plants and increase root activity.However,the effect of biostimulating hormone is not obvious in the early stage of growth and development of soybeans.With the advancement of fertility,the action of biostimulating hormone begins to appear.Therefore,it is necessary to use rhizobia solution to ensure the advantage of the early growth of soybean plants.Therefore,biostimulation is applied at the same time.Rhizobium and Rhizobium test groups S4 and S5 were better than other test groups in physiological indices such as rhizobia count,root vigor,and plant dry weight.In addition,biostimulating hormone can also increase nitrogenase activity and bean hemoglobin content,and in the concentration range of 40g/L-80g/L,the higher the concentration of biostimulating hormone,the higher the dry weight,nitrogenase activity,and bean hemoglobin of the plant,the more significant the increase in content.4.Biostimulating hormone can increase the symbiotic nitrogen fixation efficiency of plants and nitrogen-fixing bacteria,increase the protein content of soybean grain,improve the quality of soybean,and have more significant effects with the rhizobia solution.And the continuous flow analyzer was tested and verified.The result of determining the total nitrogen content of soybean was not significantly different and it was fast and efficient.It indicated that it is feasible to use the continuous flow analyzer to rapidly determine the content of soybean protein.Establish a practical method for the laboratory follow-up mass determination of soybean grain protein.