茶树根系耐铝内生真菌的筛选鉴定  

Screening and identification of aluminum-tolerant endophytic fungi in tea plant roots

作　　者：章顺成 武平安 李静[1] 丁月 吴昊 耿园明 张宽朝[1] 余梅[1] ZHANG Shuncheng;WU Ping'an;LI Jing;DING Yue;WU Hao;GENG Yuanming;ZHANG Kuanchao;YU Mei(School of Life Sciences,Anhui Agricultural University,Hefei 230036)

机构地区：[1]安徽农业大学生命科学学院,合肥230036

出　　处：《安徽农业大学学报》2021年第5期744-749,共6页Journal of Anhui Agricultural University

基　　金：国家级大学生创新项目(dg194205)资助。

摘　　要：茶树是典型的喜铝耐铝植物,其根系微生物在铝元素的吸收转化中起重要作用。从茶树根系分离鉴定出一株耐铝的内生真菌,进行了显微镜形态鉴定及18S r DNA序列分析,分析了该菌株对不同重金属的耐受程度,研究铝对该菌生长的影响,并利用电感耦合等离子原子发射光谱仪(ICP-AES)对该菌株耐受Al^(3+)进行了研究分析。结果发现,显微镜形态观察及18S r DNA序列表明该菌为粘红酵母属粘红酵母(Rhodotorula glutinis),命名为A3。粘红酵母A3对不同重金属的耐受性为:Al^(3+)>Mn^(2+)>Cu^(2+),其中铝浓度可达250 mmol·L^(-1)。当培养基中添加了150mmol·L^(-1)的Al^(3+),菌液p H值为2.0~3.0,粘红酵母A3生长良好。ICP-AES结果显示该菌株铝离子含量与培养基中Al^(3+)浓度呈正相关,说明该菌株在一定范围内对Al^(3+)具有吸附作用;同时测定该菌株的含水量随培养基中铝含量增加而增大,揭示该菌株对铝毒害的规避与其通过含水量的增加平衡细胞液有关系。分离的耐铝真菌为茶树的耐铝机制提供新的思路,并为其定殖到其他作物规避铝胁迫提供微生物资源,以提高植物的抗性,增加产量。Tea plants are typical aluminum-tolerant plants,and their root microorganisms play important roles in the absorption and transformation of aluminum.In this study,an endophytic fungi with aluminum tolerance was isolated from the roots of tea plants.Microscopic morphological identification and 18S r DNA sequence analysis were carried out to analyze the tolerance degree of the strain to different heavy metals and to study the effect of aluminum on the growth of the strain.The tolerance ability of the strain to Al^(3+)was analyzed by inductively coupled plasma atomic emission spectrometer(ICP-AES),and the results showed that the fungus belonged to Rhodotorula glutinis,numbered A3 by microscopic morphology observation and 18S r DNA sequence analysis.The tolerance of the strain to three heavy metals was:Al^(3+)>Mn^(2+)>Cu^(2+),and the strain could grow in the presence of Al^(3+)up to 250mmol·L^(-1).The p H value of the strain in the culture medium was 2.0-3.0 when 150 mmol·L^(-1)Al^(3+)was added to the medium.ICP-AES results showed that the aluminum ion content in the strain was positively correlated with the Al^(3+)concentration in the medium,which indicated that the strain has adsorption ability on the Al^(3+)in a certain range.Meanwhile,it was also determined that the water content of the strain increased with the increase of the aluminum content in the medium,which revealed that the avoidance of aluminum toxicity of the strain might be related to the equilibrium cell fluid through the increase of water content.The aluminum-tolerant fungus isolated in this study might provide new ideas for the aluminum-tolerant mechanism of tea plants,and provide microbial resources for their colonization in other crops to avoid aluminum stress,so as to improve plant resistance and increase yield.

关 键 词：茶树 耐铝 内生菌 粘红酵母 

分 类 号：S571.1[农业科学—茶叶生产加工] X172[农业科学—作物学]