3. Results
3.1. Fungal isolation and identification
Based on morphological characteristics and phylogenetic analysis of the internal transcribed spacer (ITS) sequences, two isolates collected from roots of D. nobile were identified as the members of the genus Tulasnella. The colonies of the two fungi grew at the rate of 5–6 mm/day. Three weeks after inoculated on PDA, colonies of the two isolates were white to cream-colored with regular margin (Fig. 2a). Monilioid cells are spherical to ellipsoidal, 6–10 μm × 7–20 μm, in branched (Fig. 2b and c). Result of the BLAST searches showed that the internal transcribed spacer (ITS) and 5.8S rDNA sequences of two isolates had 98% identity with the internal transcribed spacer (ITS) and 5.8S rDNA sequences of Tulasnella sp. Neighbor-joining (NJ) phylogenetic tree analysis using the internal transcribed spacer (ITS) and 5.8S rDNA sequences showed the two fungal endophytes clustered together with the Tulasnella genus with a bootstrap support of 100% ( Fig. 3).