Molecular diagnosis of the brown root rot disease agent Phellinus noxius on trees and in soil by rDNA ITS analysis. Applied Environmental Biotechnology

2018-11-23 本站

题目：Molecular diagnosis of the brown root rot disease agent Phellinus noxius on trees and in soil by rDNA ITS analysis. Applied Environmental Biotechnology

期刊：Applied Environmental Biotechnology

作者：Yon g-Feng Wang1,2，Han Meng2， Victor W. Gu3， Ji-Dong Gu2

单位：1.Guangdong Provincial Key Laboratory of Bio-control for the Forest Disease and Pest, Guangdong Academy of For-estry, No. 233, Guangshan 1st Road, Guangzhou, People’s Republic of China ；   2.Laboratory of Environmental Microbiology and Toxicology, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, People’s Republic of China ；   3.Chinese International School, 1 Hau Yuen Path, Braemar Hill, Hong Kong SAR, People’s Republic of China

摘要： Phellinus noxius is an important pathogen that causes brown root rot of trees in tropical and subtropical areas and has led to severe damage to trees. A quick and accurate diagnostic technique is essential to the timely confirmation of the pathogen and possible treatment. In this study, the fast, sensitive and accurate approach of molecular technique was used to diagnose the brown root rot pathogen on trees and in soil of subtropical Hong Kong. Two pairs of specific PCR primers were used to amplify the target rDNA internal transcribed spacer (ITS) region through polymerase chain reaction (PCR) for both tree tissue and soil samples. The amplified ITS fragments were then sequenced and analyzed phylo美高梅ally for confirming the identity of pathogen P. noxius . The results showed that 13 of 38 suspected trees in Hong Kong were infected with P. noxius positively and the pathogens in different samples showed no specific preference to the hosts and very little differences in their nucleotide sequences. Quantitative PCR was applied to both soils grown with trees identified positive for P. noxius and those negative, but the soils with healthy trees were also found positive for P. noxius . For the first time, P. noxius was reported to infect a wide range of tree species in Hong Kong and widely present in soils as a reservoir for the pathogen. Through this study, it is proposed that P. noxius is a soil-borne pathogen, which increases its infectivity when trees start to grow in the soil as a means in addition to the previously proposed root-to-root contact.

关键词：Phellinus noxius,，molecular diagnosis，brown root rot