野生与人工栽培铁皮石斛内生真菌生物多样性比较及抗炭疽病活性菌株的筛选

Biodiversity comparison of endophytic fungi from wild and artificially cultivated Dendrobium officinale and screening of fungal strains with anti-anthracnose activities

【目的】系统分析和比较野生与人工栽培铁皮石斛Dendrobium officinale内生真菌的多样性,并从中筛选抗炭疽病活性的菌株。【方法】利用组织块分离法分离铁皮石斛内生真菌,采用载玻片培养法和基于rRNA内转录间隔区基因(rDNA-ITS)的分子鉴定法对它们进行鉴定,采用平板对峙法筛选抗炭疽病内生真菌。【结果】从铁皮石斛中分离到236株内生真菌,其中132株分离自野生植株,104株分离自人工栽培植株,野生植株内生真菌的总定殖率(50.46%)、总分离率(61.11%)及多样性指数(2.95)均明显高于人工栽培植株(其相应数值分别为39.35%、48.14%和2.49);筛选到34株对胶孢炭疽菌Colletotrichum gloeosporioides具抑制活性的内生真菌菌株,其中菌株F102(蜡孔菌Ceriporia sp.)、F27(硬孔菌Rigidoporus sp.)、F103(蚁巢伞菌Termitomyces sp.)和F122(伏革菌Peniophora sp.)的抑制效果较好,抑菌率分别为93.06%、88.20%、87.48%和84.57%。【结论】野生与人工栽培铁皮石斛内生真菌的生物多样性和类群结构具有明显差异,并且其中蕴含着丰富的抗炭疽病活性菌株,这为人工栽培铁皮石斛药材品质的改良及其炭疽病的生物防治奠定了基础。

【Objective】To systematically analyze and compare the diversity of endophytic fungi from wild and cultivated Dendrobium officinale,and screen fungal strains with anti-anthracnose activities.【Method】Endophytic fungi of D.officinale were isolated by tissue block separation method,and they were identified by slide culture method and molecular identification method based on internal transcribed spacer regions of ribosomal DNA(rDNA-ITS).Screening for endophytic fungi against anthracnose was carried out by plate method.【Result】Totally 236 endophytic fungal strains were isolated from D.officinale(132 from wild plants and 104 from artificially cultivated plants).Total colonization rate(50.46%),total isolation rate(61.11%)and diversity index(2.95%)of endophytic fungi in wild plants were significantly higher than those in artificially cultivated plants(the corresponding values were 39.35%,48.14% and 2.49,respectively).We screened out 34 strains of endophytic fungi with inhibitory activities against Colletotrichum gloeosporioides.Amomg them,the strains Ceriporia sp.F102,Rigidoporus sp.F27,Termitomyces sp.F103 and Peniophora sp.F122 showed higher inhibitory effects,and their inhibition rates were 93.06%,88.20%,87.48% and 84.57%,respectively.【Conclusion】The biodiversity and community structure of endophytic fungi of wild D.officinale and artificially cultivated D.officinal had significant differences,and abundant strains with anti-anthracnose activities were obtained from them,which lays the foundation for improving the quality of medicinal materials of artificially cultivated D.officinal and the biocontrol of D.officinale anthracnose.