In planta distribution of Pyrrhoderma maxium, the causal agent of brown root rot of mango
2023
Takashi, M. | Kikuno, H. | Kajikawa, A. | Yokota, K.
Pyrrhoderma noxium, a basidiomycete fungus, is the causal agent of brown root rot disease on trees occurred in tropical and subtropical regions. More than 200 woody plant species have been reported as host plants including mango (Mangifera indlca). In Miyakojima island, Okinawa, Japan, brown root rot of mango is a serious problem. The pathogen can spread not only via airborne basidiospores but also via root-to-root contact of host plants. However, there are few papers described about the distribution of pathogen in planta and its survivability. In this study, authors aimed to clarify distribution of the pathogen and its survivability in the root tissues of diseased trees occurred in a green-house located in Miyakojima. To detect the pathogen in plant tissue, a selective medium was used for culture method. The main and lateral roots of 2-diseased trees, which differed length of time since onset of disease (for 1 and 17 months), were collected and used for detection. The pathogen was detected in whole of the root samples including at the center of 14 cm diameter of main root in newly diseased tree as well as the other tree. To detect the pathogen in rhizosphere, DNA was extracted from soil and used as a template for PCR using a specific primer set. The pathogen was detected in the rhizosphere of old tree whereas no detection of new one. Data strongly suggested that the fungal pathogen can spread in the main and lateral roots of mango tree. It was also suggested that the pathogen can survive for more than 17 months in the root tissue and discharged from infected root tissues to rhizosphere.
显示更多 [+] 显示较少 [-]