The rDNA ITS diversity of mycorrhizal fungi with Cypripedium flavum

Abstract

Cypripedium plants, which are endangered by over-harvesting due to their high ornamental and medicinal value, use mycorrhizal fungi to guarantee cultivation and conservation. In order to explore the diversity of mycorrhizal fungi, the rDNA internal transcribed spacer （ITS） sequences from mycorrhizal fungi of four C. flavum populations （Baishui River, Shika Snow Mountain, Tiansheng Bridge, and Napa Village） were amplified by nested polymerase chain reaction （PCR） methods. Results showed a total of 336 distinct ITS-taxa of C. flavum obtained from clones of mycorrhizal fungi with populations from Baishui River （93）, Shika Snow Mountain （90）, Tiansheng Bridge （103）, and Napa Village （80）. Blast results of rDNA ITS sequences showed a rich diversity in mycorrhizal fungi systems with mycorrhizae belonging to Tulasnella, Corticium, Epulorhiza, and Rhizoctoia. Tulasnella fungi probably had host-specificity and growth-promoting effects on C. flavum. These results may provide a scientific basis for further conservation work of C. flavum and fungal manure development.［Ch, 1 fig. 3 tab. 24 ref.］