碱蓬内生真菌JP3的分离、鉴定及促生作用研究

Isolation,identification and growth-promoting effect of Suaeda salsa endophyte fungus JP3

为研究盐生碱蓬(Suaeda glauca)植物体内生菌及其产生的生物学活性物质对植物的促生长作用,利用组织分离法对碱蓬内生菌进行分离;用水培法测定碱蓬内生真菌对水稻幼苗株高、干重、叶绿素含量等生理指标的影响;对具有明显促生活性的菌株根据形态、培养特征和18SrDNA测序分析进行分类鉴定。从健康碱蓬植株的根、茎、叶中分别分离出19株、70株和49株,共138株内生菌,其中细菌13株、真菌122株、放线菌3株;筛选出对水稻幼苗具明显促生活性的真菌JP3,由该菌处理的水稻幼苗与对照相比其干重增加12.23%,株高增加15.6%(P<0.05),总叶绿素含量增加了13.2%;18SrDNA测序和比对结果显示JP3属Glomerella cingulata,相似性大于97%。研究表明:碱蓬植物内生菌具有丰富、多样的特点,是产生促生物学活性物质的重要微生物资源,可为开发新的植物促生剂提供生物源物质。

Endophytes were isolated from Suaeda salsa by tissue isolation to study the effects on promoting plantgrowth. Hydroponic experiments were carried out to study the role of endophyte fungi on rice seedling growth. Riceshoot height, dry weight and chlorophyll （Chl） content were determined. Strains were identifieated according toendophytes morphology, characteristic and 18S rDNA sequencing results, la8 endophytes were isolated from the roots（19 endophytes）, stems （70 endophytes） and leaves （49 endophytes） of Suaeda glauca, respectively, including 13endophyte bacteria, 122 endophyte fungi and 3 endophyte actinomyces. Endophyte fungus JP3 which promoting riceseedling growth was screened. Shoot length, dry weight and chlorophyll （Chl） content of rice treated with endophytefungus JP3 were significantly increased by 15.6%, 12. 23% and 13.2%, respectively of the control. Endophyte fungusJP3 belonged to Glornerella cingulata family and had 97% similarity to other Glornerella sp strains according to 18SrDNA sequencing results. The results showed that endophytes isolated from Suaeda glauca had the traits of rich anddiversity, which were the important microorganism resources and supplied biological source substances to exploit newplant growth promoting agent.