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应用生态学报 ›› 2012, Vol. 23 ›› Issue (02): 519-524.

• 研究论文 • 上一篇    下一篇

柠条根瘤内生细菌的抗逆性及遗传多样性

代金霞,王玉炯**,武雪娟,张晓玲   

  1. 宁夏大学生命科学学院, 银川 750021
  • 出版日期:2012-02-18 发布日期:2012-02-18

Stress resistance and genetic diversity of endophytic bacteria isolated from Caragana spp. root nodules.

DAI Jin-xia, WANG Yu-jiong, WU Xue-juan, ZHANG Xiao-ling   

  1. School of Life Science, Ningxia University, Yinchuan 750021, China
  • Online:2012-02-18 Published:2012-02-18

摘要: 采用16S rDNA PCR-RFLP和序列分析方法对分离自柠条根瘤的40株内生细菌的遗传多样性及系统发育进行分析,并对菌株的耐盐性、耐酸碱性和生长温度范围进行测定.结果表明: 40株供试菌株共产生9种遗传图谱类型;对各类型代表菌株进行16S rDNA序列测定,结合形态特征和生理生化检测结果,表明供试菌株分别归属于芽孢杆菌属(Bacillus)、Inquilinus属、申氏杆菌属(Shinella)和不动杆菌属(Acinetobacter),遗传多样性较为丰富;57.5%的菌株可耐受4%的NaCl,75%的菌株可在pH 11.0的条件下生长,85%的菌株经60 ℃热激处理后仍能继续生长,显示柠条根瘤内生细菌具有较强的抗逆性,菌株LWEN 07和LWEN 15抗逆能力最为显著.

关键词: 柠条, 内生细菌, 抗逆性, 16S rDNA, 系统发育

Abstract: By adopting PCR-RFLP and 16S rDNA sequencing, this paper analyzed the genetic diversity and phylogeny of 40 endophytic bacterial strains isolated from Caragana spp. root nodules, and determined the salt resistance, acid- and alkali resistance, and growth temperature range of the strains. A total of 9 genotypes were obtained from the 40 strains by RFLP. The 16S rDNA sequencing, morphological observation, and biochemical test of representative strains showed that the strains belonged to Bacillus, Inquilinus, Shinella and Acinetobacter, respectively, and had rich genetic diversity. 57.5% of the strains could tolerate 4% NaCl stress, 75% of the strains could grow in YMA medium with an initial pH 11.0, and 85% of the strains could survive after heat shock treatment at 60 ℃, suggesting that the endophytic bacteria of Caragana spp. had strong resistance capacity. Among the strains, LWEN 07 and LWEN 15 were most resistant.

Key words: Caragana spp., endophytic bacteria, stress resistance, 16S rDNA, phylogeny