Isolation and Identification of a Fungal Disease from Bletilla striata

Purpose In order to clear the pathogen causing leaf lesion with brown-black circle spot of Bletilla striata.

Method This study was isolated and purified the sample of B. striata collected from Funing County, Yunnan Province, through morphological identification and verification of Koch's Postulates to verify if the strain could cause the same diease of B. striata .

Result The strain could cause the same diease of B. striata as the sample, and it was finally identified as Daldiniasp. by morphological observation and rDNA-ITS sequence analysis. The strain was numbered BJ-HTKLC, the colony morphology and microstructure were described as following: black brown in middle, marginal gray, concentric whorl, attachment base growth, aerial mycelium growth slower, hyphae villous; hyphae with septa, branched, 9-20 μm wide, average 13 μm wide, spore morphology were elliptical or kidney line, 11-16 (17.8) μm×6-9 (10.2) μm. ITS sequence had the highest similarity to D. concentrica, which was 97.1%.

Conclusion BJ-HLCTK belongs to the genus of Daldiniasp., and which has the highest close to fungus D. concentricaspecies (D. consentrica) . The fungus is mainly harmful to a variety of broad-leaved tree species and damaged xylem to form mottled rot. In this study, we first reported that the host of this pathogen was Rhizoma Bletillae.