干旱区生态环境知识资源中心(Arid): 宁夏荒漠草原小叶锦鸡儿可培养内生细菌多样性及其分布特征

Arid

	宁夏荒漠草原小叶锦鸡儿可培养内生细菌多样性及其分布特征
其他题名	Diversity and distribution of endophytic bacteria isolated from Caragana microphylla grown in desert grassland in Ningxia
	代金霞; 王玉炯
来源期刊	生态学报
ISSN	1000-0933
出版年	2012
卷号	32 期号:20 页码:6300-6307
中文摘要	对宁夏荒漠草原小叶锦鸡儿各部分组织中可培养内生细菌的遗传多样性和分布特征进行了分析,并对菌株的耐盐性、耐酸碱性和生长温度范围进行了测定。结果表明:各部分组织中内生细菌的数量和群落组成存在明显差异,根部细菌种群密度最大,分离数量最多,叶部次之,茎部和种子数量最少。78株分离菌株经16SrDNA-RFLP分析共产生9种遗传图谱类型,16SrDNA序列分析表明供试菌株分别归属于芽孢杆菌属、类芽孢杆菌属、假单胞菌属、贪铜菌属、罗尔斯顿菌属和中华根瘤菌属,与其它植物相比多样性较为单一;芽孢杆菌属是小叶锦鸡儿的优势内生菌群(占87.2%),分布于所有组织中。菌株的抗逆能力较强,多数菌株可耐受6%的NaCl,能在pH值5.010.0及45℃的条件下生长,3株芽孢杆菌属细菌具有较强的耐盐、耐酸碱、耐高温性能。
英文摘要	Endophytic bacteria can be defined as those bacteria that can colonize the internal tissue of a plant without causing negative effects on their host.Many endophytes can be used as agents for stimulating plant growth,and for producing bioactive natural compounds as a potential source of novel products for use in medicine,agriculture,and industry.Therefore,the study of plant endophytic bacteria is important for understanding ecological interactions and for the development of biotechnological applications.We studied the diversity,distribution,and stress resistance of endophytic bacteria isolated from Caragana microphylla,a perennial leguminous shrub that is highly tolerant to drought,salt,and extreme cold environment,from desert grassland in Ningxia,China.A total of 78 bacterial strains were isolated,and the quantity and community composition of endophytic bacteria in various tissues of C.microphylla were found to be markedly different.The bacteria colonizing in the roots was greater than that of other tissues(40 strains),followed by leaves(20 strains).The genetic diversity and phylogenetic position of the isolates were analyzed using restriction fragment length polymorphisms(RFLP) and sequence homology comparisons of the 16S rDNA gene.The isolates were classified into 11 types on the basis of PCR-RFLP results,and strains were determined to belong to six genera from five families based on 16S rDNA sequence analysis.The endophytic bacterial population of C.microphylla was found to be less diverse than that of other plants,and colonized predominantly by Bacillus species(87.2%),which were distributed in all tissues of the plant.The bacterial populations in the roots consisted of Bacillus(89.6%) and Paenibacillus,which included isolates belonging to rDNA types 16.The bacterial populations found in leaf tissue consisted of Bacillus and Ralstonia species,while bacteria found in the stems were mainly Bacillus,Pseudomonas,and Sinorhizobium species.Bacillus,Pseudomonas,and Cupriavidus species were isolated from seeds.Tests for stress resistance revealed that most of the isolates could tolerate NaCl stress at 6% concentration,and could grow at an initial pH of 5.011.0 and at a temperature of 1045℃.A small number of isolates could tolerate NaCl stress at 10% concentration,and could grow at pH 12.0 at a temperature of 55℃.None of the isolates could grow below pH 4.0 and at a temperature of 4℃.The stress resistance of endophytic bacteria was different in various tissues,and root bacteria showed greater levels of resistance than strains isolated from other tissues.However in general,the endophytic bacteria of C.microphylla had a strong resistance capacity,among which,three strains of Bacillus were most resistant.The results of this study not only offer new information about the C.microphylla endophytes under extreme environmental conditions,but also add to our knowledge regarding the protection and utilization of microbial resources in arid areas during the management of desertification.
中文关键词	极端环境 ; 小叶锦鸡儿 ; 内生细菌 ; 遗传多样性 ; 抗逆性
英文关键词	extreme environment Caragana microphylla endophytic bacteria genetic diversity stress resistance
语种	中文
国家	中国
收录类别	CSCD
WOS类目	FORESTRY
WOS研究方向	Forestry
CSCD记录号	CSCD:4654611
来源机构	宁夏大学
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/228482
作者单位	宁夏大学生命科学学院, 银川, 宁夏 750021, 中国
推荐引用方式 GB/T 7714	代金霞,王玉炯. 宁夏荒漠草原小叶锦鸡儿可培养内生细菌多样性及其分布特征[J]. 宁夏大学,2012,32(20):6300-6307.
APA	代金霞,&王玉炯.(2012).宁夏荒漠草原小叶锦鸡儿可培养内生细菌多样性及其分布特征.生态学报,32(20),6300-6307.
MLA	代金霞,et al."宁夏荒漠草原小叶锦鸡儿可培养内生细菌多样性及其分布特征".生态学报 32.20(2012):6300-6307.