Morphological and Molecular Identification of Peach Brown Rot Disease in Tibet and Exploration of the Biocontrol Efficiency of .

Brown rot caused by the pathogen of the genus is the most destructive disease in peaches worldwide. It has seriously reduced the economic value of the peach ( (L.) Batsch) in Nyingchi and Qamdo, Tibet, China. , and have been reported as the causal agents of brown rot disease on stone fruits in China. In this study, we report on the identification of in peach orchards in Nyingchi and Qamdo, Tibet. From twenty-three isolates with the same characteristics, we identified the representative single-spore isolates T8-1, T8-8, and T8-20 as and confirmed that the Tibet brown rot disease was caused by based on the morphological characteristics and molecular analyses. The phylogenetic analysis of the glyceraldehyde-3-phosphate dehydrogenase () and β-tubulin () nucleotide sequences and the multiplex PCR identification revealed that the representative isolates T8-1, T8-8, and T8-20 were more closely related to than other species. Furthermore, the biocontrol strain of T6 presented significant antagonistic activity on the T8-1 isolate (T8-1) among the five strains. The highest inhibitory rates for T6 and its fermentation product against T8-1 mycelial growth were 72.13% and 68.25%, respectively. The obvious inhibition zone displayed on the colony interaction area between the colony of T8-1 isolate and T6 and the morphological characterization of the T8-1 hyphae were enlarged and malformed after inoculation with the T6 fermentation product at 20-fold dilution. Our results indicate that the strain of T6 could be considered as a beneficial biocontrol agent in managing brown rot of peach fruit disease.