寡营养型类节杆菌OM7的分离鉴定及固沙特性

Isolation,Identification and Sand-Fixing Characteristics of Oligotrophic Paenarthrobacter sp.OM7

生物土壤结皮能有效改善沙漠土壤特性,防治荒漠化。土壤微生物尤其是寡营养型微生物是生物结皮形成过程中不可或缺的重要角色。在毛乌素沙地苔藓结皮样品中分离筛选得到寡营养型固沙菌株OM7,并通过生理生化和16S rRNA基因进行鉴定,对菌株OM7的固沙特性进行初步研究,以期为沙漠生态治理提供优良菌种资源。在淀粉稀释度为1/40的高氏一号培养基中进行发酵培养,在沙罐中均匀施洒菌液后通过测定结皮厚度和抗压强度来研究菌株OM7的固沙能力。初步鉴定菌株OM7为类节杆菌OM7(Paenarthrobacter sp.OM7),为寡营养型类节杆菌的首次报道。类节杆菌OM7在1/40高氏一号培养基中培养3天的发酵液,于沙罐内接种菌剂培养物后在1个月内所形成结皮最厚为1.83 mm,抗压强度最大为10.48 N。寡营养型类节杆菌OM7具有高效固沙能力,适应养分贫瘠的环境,使其在沙漠生态治理中更具优势。菌株OM7的固沙能力与其生长状态呈正相关,发酵时间的选取对于固沙效果至关重要。

Biological soil crusts can effectively improve desert soil characteristics and prevent desertification.Soil microorganisms,especially oligotrophic microorganisms,play an indispensable role in the formation of biological crusts.The oligotrophic sand-fixing strain OM7,isolated and screened from the moss crust sample of Mu Us Sandy Land,was identified by physiological and biochemical tests and 16S rRNA gene analyses.In addition,its sand-fixing properties were studied,in order to provide excellent strain resources for the ecological restoration of desertification.The fermentation was carried out in Gause's synthetic medium with starch dilution of 1/40.The sand-fixing ability was assessed by measuring the crust thickness and compressive strength after evenly sprinkling the fermentation broth in sand tanks.The strain OM7 was preliminarily identified as Paenarthrobacter sp.OM7,which is the first report of oligotrophic strains from the genus Paenarthrobacter.After the fermentation broth of P.sp.OM7 was sprinkled,which cultured in 1/40 Gause's synthetic medium for 3 days,the maximum thickness of crusts formed within 1 month was 1.83cm,and the maximum compressive strength was 10.48 N.Oligotrophic P.sp.OM7 has excellent sand-fixing ability and adapts to the nutrient-poor environment,making it more advantageous in desert ecological restoration.The sand-fixing ability of P.sp.OM7 is positively correlated with its growth state,and the selection of fermentation time is very important for the sand-fixing effect.