ISOLATION AND CHARACTERIZATION OF FUNGAL ENDOPHYTES FROM DENDROBIUM CRUMENATUM SW. AND DENDROBIUM NODOSUM DALZELL (ORCHIDACEAE)

Abstract

Orchids rely on specific fungal association for seed germination and early growth. Apart from mycorrhizal fungi within orchid roots, many of the nonmycorrhizal endophytic fungi have also been reported. Although orchids host many non-mycorrhizal fungi in leaves, studies on such fungi especially in tropical and subtropical orchids have been few. The present study established the presence of non-mycorrhizal fungi in leaves of two orchids Dendrobium crumenatum Sw. and Dendrobium nodosum Dalzell. The endophytic colonies were separated from leaf segments and cultured under laboratory conditions for extraction of the DNA. The DNA samples were sequenced using 18S rRNA ITS universal primers and the resultant data was analysed using NCBI BLAST tool. The sequence of the fungus isolated from Dendrobium crumenatum (513bp) showed 95% similarity to Aspergillus flavus and that of Dendrobium nodosum (556bp) had 96% similarity to Rhizopus oryzae