红碱淖湖滨土壤微生物及稀有放线菌研究

Soil microorganism and actinomycetes resources in Hongjiannao Lake

【目的】分析陕西神木红碱淖湖滨土壤理化性质、微生物资源及稀有放线菌资源的分布,为沙化环境下放线菌资源利用及红碱淖地区生态保护与植被恢复提供科学依据。【方法】2009-09,在红碱淖的北岸、西岸、南岸共采集12个土样,对土样的理化性质和微生物区系进行分析,并采用5种放线菌培养基对该地区土壤中的放线菌进行了分离,对具有特殊形态的13株放线菌进行16SrDNA鉴定。【结果】①红碱淖地区土壤pH值均在8.2以上,最高值接近10,土壤中碱解氮、速效钾、速效磷含量分别在7.00～79.10,24.84～71.73,2.34～5.30mg/kg。②红碱淖地区土壤细菌、放线菌和真菌数量分别为105～107,102～104,101～103 CFU/g;微生物生物量碳含量在43.94～608.80mg/kg,其与土壤微生物数量之间相关性达极显著水平(P<0.01)。③改良HV琼脂培养基对红碱淖地区放线菌具有较好的分离效果。④16SrDNA测序比对结果显示,红碱淖地区放线菌资源以诺卡氏菌属(Nocardia)和链霉菌属(Streptomyces)为主;稀有放线菌占到23.08%,分属于拟诺卡氏菌属(Nocardiopsis)、糖丝菌属(Saccharothrix)和Actinophytocola。【结论】红碱淖地区的土壤属于碱性或者强碱性,土壤肥力较低;该地区蕴含着丰富的放线菌资源。

This study aimed to investigate the soil physical and chemical properties,microbial resources and the distribution of rare actinomycetes in Hongjiannao area,Shaanxi.【Method】In September 2009,12 soil samples were collected from south coast,west coast,north coast of Hongjiannao Lakeside.The soil physic-chemical properties and microbial resources were analyzed.Five medium were used to isolate the actinomycetes in soil samples and 13actinomycetes with special forms were identified using 16S rDNA sequence.【Result】①The soil pH values were8.2with highest pH close to 10,and the contents of alkali-hydrolysable N,available K,and available P were 7.00-79.10,24.84-71.73,and 2.34-5.30 mg/kg,respectively.②The population of bacteria,actinamyces,fungi were 10 5-10 7,10 2-10 4,10 1-10 3 CFU/g respectively,and the contents of microbial biomass carbon were in the range of 43.94-608.80 mg/kg,indicating that there was a significant relationship between them（P0.01）.③Improved HV agar medium showed effective actinomycetes separation among five medium.④16SrDNA sequence analysis showed rare actinomycetes accounted for 23.08%,belonging to Nocardiopsis,Saccharothrix and Actinophytocola,respectively.【Conclusion】The result revealed that soil in Hongjiannao Lake was alkaline and bar-ren,and actinomycetes were very rich.