Diversity Analysis And Polyphasic Taxonomy Of Actinobacteria Of There Plant’s Rhizosphere Soil Samples In Ebinur Lake Wetland

This paper summarized the contribute of actinomycetes in human life and the polyphasic taxonomy and the technical methods of it from different environments were reviewed. This thesis was aimed at the Ebinur Lake Wetland National Nature Reserve rhizosphere soil collecting from Xinjiang. Measured physicochemical characteristics, and diversity of actinomycetes, and secrete special antibacterial substance. The actinomycetes which have been isolated were classed by the polyphasic taxonomy technique. We discussed the influence complication of the diversity of actinomycete and soil physicochemical characteristics from different seasons. To reveal the ecological distribution and regional specificity and the activity of potential strain value of rhizosphere actinomycetes, and rhizosphere actinomycetes diversity in the wetland ecosystem potential ecological indicator was researched in the Ebinur lake wetlands.To provide a reference for Xinjiang Ebinur Lake Wetland Nattural Reserve District degraded wetland restoration research, using 5 point sampling method to collect rhizosphere soil of 3 plants area(Halocnemum strobilaceum, Salicornia europaea, Phragmites australis) in Ebinur Lake Wetland, including the lakeshore region of Bird island Protection Station and the floodplain of Jinghe saltworks were collected at May, July and December three different times as samples. The soil moisture content(MC), p H, electrical conductivity(EC), organic matter(OM), available nitrogen(AN), available phosphorus(AP), available potassium(AK), nitrate nitrogen(NN), ammonium nitrogen(AMN) and soil eight were measured quantificationally. The correlation in main plant type and physicochemical indexes of soil were analyzed.The results showed that, the soil moisture content was lower on the whole, didn’ t have a significantly correlation with the sampling plot and season, the p H was higher belonging to a alkaline soil, the electrical conductivity had a significantly negative correlation with season; the soil Na+、Ca2+、Mg2+、SO42-、Cl- et.al Ions content were at a relatively high level, the 3 rhizosphere soils are Cl- or CO32-Salinity type; The soil organic and available phosphorus matter content was higher on the whole, the average available nitrogen,nitrate nitrogen(NN) and ammonium nitrogen(AMN) content was in a relatively lower level, the average available potassium content was in a higher condition, in rhizosphere soil of Halocnemum strobilaceum >Phragmites australis >Salicornia europaea. The soil quality of the Ebinur Lake Wetland was following the law of the rhizosphere soil of Phragmites australis >the rhizosphere soil of Salicornia europaea >the rhizosphere soil of Halocnemum strobilaceum.To better understand unculture rhizosphere actinomycetes and community composition in the Ebinur Lake Wetland, and the relationship between the diversity of actinomycete and soil physicochemical characteristics were analyzed. The polymerase chain reaction denaturing gradient gel electrophoresis(PCR-DGGE) indicated that there are obviously differences in different rhizosphere soil of vegetation andin different seasons. The trend of diversity is that the highest Salicornia europaea community area,Phragmites australis community is the second lower and Halocnemum strobilaceum community area lowest. With the change of seasons, the diversity of actinomycete in rhizosphere soil of Halocnemum strobilaceum increased gradually, however, the diversity of actinomycete was that summer > autumn >spring in rhizosphere soil of Halocnemum strobilaceum and Salicornia europaea. 22 bands from DGGE profiles were sequenced in total, the analysis of sequence indicated that the main populations of actinomycete in rhizosphere soil were Actinomycetales,Corynebacterineae,Micrococcineae,Frankineae,Acidimicrobineae, Kineosporiineae and unknown group of bacteria. Correlation analysis showed that there were the positive relationship between the diversity of actinomycete and soil organic matter and moisture content, meanwhile, it had a negative correlation with electrical conductivity, p H, available potassium,available phosphorus and available nitrogen in Ebinur Lake Wetland in Xinjing.5 culture medias were isolated and choose the actinomycetes from the 3 rhizosphere soils by plate paint isolation methods, obtained 116 actinomycetes in the Ebinur Lake Wetland. Antagonistic function of116 strains antagonistic actinomycete on 3 bacterials and 5 plant pathogenic fungi were studied.Antagonistic tests showed that all of actinomycetes strains were obtained approximately 42.24% inhibition strains, and 5 strains of which have better antagonistic action against five pathogens, and the inhibition zone were more than 15 mm. The 5 actinomycetes which have been secondary screening were classed by the polyphasic taxonomy technique, and the strain N1-30, N2-11, N2-12 preliminary optimization of fermentation conditions. The results showed that the average inhibition rate of strains N1-30, N2-11, N2-12, N3-2 and N3-5 were 67.23%、69.91%、64.51%、61.61% and 61.72% to four pathogens; The optimized fermentation for strains N1-30、N2-11、N2-12 were obtained,which reached 70% to four pathogenic fungis.Five isolates were putatively identified to genus level based on 16 S r RNA gene sequence analysis, which belong to the genus Streptomyces.