铁皮石斛促生长内生真菌的筛选与鉴定  

Screening and identification of endophytic fungi with growth promoting effect on Dendrobium officinale

作　　者：侯晓强[1,2] 郭顺星[1] 

机构地区：[1]中国医学科学院北京协和医学院药用植物研究所,北京100193 [2]廊坊师范学院生命科学学院,河北廊坊065000

出　　处：《中国中药杂志》2014年第17期3232-3237,共6页China Journal of Chinese Materia Medica

基　　金：国家自然科学基金项目(31100314);博士点基金优先发展领域项目(20131106130002);河北省自然科学基金项目(C2012408007);中国医学科学院药用植物研究所创新团队发展计划项目(PIRTI-IT1302)

摘　　要：石斛生境中存在多种能够促进石斛生长的内生真菌,利用内生真菌与铁皮石斛组培苗共生培养,筛选对铁皮石斛组培苗有促生长活性的内生真菌,研究内生真菌对石斛根的侵染情况,采用形态鉴定和分子鉴定的方法对促生长活性内生真菌进行鉴定。结果表明,8株内生真菌对铁皮石斛苗有促生长作用,均能侵染铁皮石斛根,在铁皮石斛根的根被、外皮层、皮层中以菌丝或菌丝团的形式存在,不侵染内皮层和中柱,区别于有害真菌。8株活性内生真菌中,2株产孢真菌经形态鉴定,属于Pestalotiopsis,Eurotium属,6株不产孢真菌经分子鉴定,分别属于Pyrenochaeta,Coprinellus,Pholiota,Alternaria,Helotiales等5个属。促生长活性内生真菌与石斛组培苗共生培养,可促进石斛组培苗生长,对于缩短石斛生长周期,增加石斛中药材资源具有指导意义。The endophytic fungi with plant growth promoting effects were screened by co-culture of each endophytic fungus and seedlings of Dendrobium officinale. Anatomical features of the inoculated roots were studied by paraffin sectioning. Morphological characteristics and rDNA ITS1-5.8S-ITS2 sequences were applied for the taxonomy of endophytic fungi. The results showed that 8 strains inoculated to D. officinale seedlings greatly enhanced plant height, stem diameter, new roots number and biomass. According to the anatomical features of the inoculated roots, each fungus could infect the velamina of seedlings. The hyphae or pelotons were existed in the exodermis passage cells and cortex cells. The effective fungi could not infect the endodermis and vascular bundle sheath, but which was exception for other fungi with harmful to seedlings. Combined with classic morphologic classification, 2 effective strains were identified which were subjected to Pestalotiopsis and Eurotium. Six species of fungi without conidiophore belonged to Pyrenochaeta, Coprinellus, Pholiota, Alternaria, Helotiales, which were identified by sequencing the PCR-amplified rDNA ITS1-5.8S-ITS2 regions. The co-culture technology of effective endophytic fungi and plant can apply to cultivate the seedlings of D. officinale. It is feasible to shorten growth cycle of D. officinale and increase the resource of Chinese herbs.

关 键 词：铁皮石斛 内生真菌 促生长活性 侵染检测 菌种鉴定 

分 类 号：S567.239[农业科学—中草药栽培]