Diversity Of AMF In Rhizosphere Soil Of Codonopsis Pillosula And Its Inoculation Effect With PGPR On Codonopsis Pillosula

The diversity of arbuscular mycorrhizal fungi(AMF)and the inoculation effect of AMF and Plant rhizosphere-promoting bacteria(PGPR)of Codonopsis pillosula were studied.From July 2017 to October 2017,9 sampling sites were selected in Lingchuan County,Huguan County and Pingshun County,Changzhi City,Shanxi Province.Each site was repeated 3 times.A total of 27 soil samples and root samples of C.pillosula were collected.In order to investigate the AMF diversity,soil physical and chemical properties,rhizosphere microbial community diversity of Codonopsis pillosula by wet sieve decantation method,high-throughput sequencing,Biolog and other methods.Highly efficient phosphate solubilizing bacteria: Pseudomonas fluorescens M11,Serratia urealyticum DW2,ACC deaminase-producing bacteria: Klebsiella pneumoniae LDS17 and the dominant AMF of C.pillosula rhizosphere: Glomus versiformis were inoculated with the rhizosphere of Potted C.pilosula.The physiological indexes such as seedling height,leaf area,ground diameter,chlorophyll content,soil enzyme activity and soil physical and chemical properties were determined.The effects of AMF and PGPR inoculation on the growth of C.pilosula were revealed,which provided theoretical guidance for the artificial cultivation of C.pilosula and its high-efficiency compound microbial fertilizer.The main results are as follows:1.A total of 32 species of AMF 8 genus were isolated from the rhizosphere of C.pilosulae,including 14 species of Acaulospora,accounting for 43.75%;9 species of Glomus,accounting for 25.00%;4 species of Funneliformis belongs to,accounting for 12.50%;Claroideoqlomus has 2 species,accounting for 6.25%;Scutellospora,Ambispora and Archaeospora all have one specie,accounting for 3.13% respectively.Acaulospora and Glomus were found in every site,and belonged to the AMF dominant genus of the rhizosphere of C.pilosula.Archaeospora paulinae,Claroideoqlomus claroideum,Funneliformis badium and Archaeospora undulata as characteristic species,only appear in the site Cp-DM,Cp-NN,Cp-DM and Cp-SZ respectively.2.Typical AMF structures were observed after staining of root samples of C.pilosula collected from 9 research sites,mainly root hyphae and extra-root hyphae,root vesicles and arbuscular.Root length colonization rate(RLC)was 65.33-83.33%,vesicle colonization(VC)was 9.33-38.67%,arbuscular colonization(AC)was 38.00-68.00%,and spore density(SD)was 66-379/50 g dry soil.The soil parameters of the nine plots have their own characteristics,the soil pH is 8.176-8.290;Cp-FT contains high content of available phosphorus(86.833 mg / kg)and urease(0.638 mg / g),but the lowest total nitrogen content(1.307g)/ kg);Cp-LJ content of high nitrogen and organic matter were 5.787 g / kg and 8.937 g / kg,respectively,and effective phosphorus content was low(13.038 mg / kg).Cp-NN and Cp-DP have the highest invertase and The lowest organic content.The lowest of invertase and urease were found in Cp-EW.3.The sequence clustering from the 454 pyrosequencing operation was clustered into the operational taxonomic unit(OTU)defined by 97% sequence similarity,and a total of 102,751 sequences and 3,474 OTUs were identified,and finally generated 227 OTUs based on 97% sequence similarity.227 OTUs belong to 8 AMF genus,while the unidentifiable definition is others.Glomus is the most abundant genus of all sites.The number of OTUs in 27 soil samples ranged from 113 to 149,and there was no significant difference in the AMF richness and diversity of AMF at 9 locations.According to the goods_coverage index is close to 1,the samples is reasonable,the sequencing results can represent the real situation of the sample,and more samples will only produce a small amount of OTU.Among all the sample points,the highest richness and diversity of OTU is Cp-LJ(Chao1 = 153.44,observed_species = 136.63),and the minimum richness and diversity of OTU is Cp-PS(Chao1 = 134.45,observed_species = 115.97).The most common microbial communities are Cp-SZ(shannon = 4.92)and Cp-FT(shannon = 3.70).All of these indicate a certain difference in the abundance and diversity of the AMF community at nine sites.4.There were some differences in the utilization ability of microbial communities in the rhizosphere soil of the nine sites to the single carbon source.The average utilization rate of carbon sources in the nine plots(AWCD)showed an upward trend,but the extent of the increase was slightly different.When the culture reached 168 h,the upward trend of the utilization of carbon sources in the eight plots was basically the same,and only one minor differences;while the utilization of Cp-NN on carbon sources increased slowly,which was significantly lower than the other eight plots.The AWCD values of the nine sites were as follows: Cp-PS>Cp-DM>CpYD>Cp-DP>Cp-LJ>Cp-SZ>Cp-EW>Cp-FT>Cp-NN.There is a certain difference in the microbial community diversity index of the rhizosphere of Codonopsis pilosula,but there is no regulation.It may because soil microbes exhibit different activities in different habitats,and the ability to utilize carbon sources in microplates is also will be differences.The main carbon sources used in the soil microbial community in the rhizosphere of Codonopsis pilosula are sugars,amino acids and esters.The red parts of Cp-DM,Cp-YD,Cp-FT,Cp-DP,Cp-EW and Cp-SZ in the Heatmap cluster analysis were mostly,indicating that the microbial communities in these six sites had the strongest function.The utilization of carbon sources in ecological microplates is also the strongest.5.Whether the single inoculation(AMF or PGPR)or double inoculation and triple(AMF+PGPR)compared with the control CK treatment,the seedling height,ground diameter and leaf area of the Codonopsis pilosula seedlings were observed at 30 d,60d and 90 d.It was found that the growth of Codonopsis pilosula seedlings inoculated at different time periods was significantly better than that of the control group,and the growth of mixed inoculated seedlings was better than that of single inoculation.At 90 days,the chlorophyll content of Codonopsis pilosula seedlings was significantly higher than that of the control group.There was no significant difference in leaf chlorophyll content between PGPR and AMF+ PGPR,indicating that there was no significant effect of chlorophyll content on AMF.Mixed inoculation of AMF and PGPR can also significantly increase the content of N and P in the soil and the enzyme activity of the soil.The above results indicate that AMF and PGPR have synergistic effects and are expected to provide a theoretical basis for the development of microbial fertilizer of Codonopsis pilosula.