Isolation and identification of a new phytopathogen causing root rot of Rehmannia glutinosa.
10.19540/j.cnki.cjcmm.20210227.102
- Author:
Yong LI
1
;
Rong WANG
1
;
Hui-Qing CHEN
1
;
Ruo-Fan WEI
1
;
Kun LIU
1
;
Wan-Long DING
1
Author Information
1. Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100193, China.
- Publication Type:Journal Article
- Keywords:
Rehmannia glutinosa;
molecular identification;
phytopathogen;
root rot
- MeSH:
DNA, Ribosomal;
Fungi/genetics*;
Plant Leaves;
Rehmannia/genetics*;
Seedlings
- From:
China Journal of Chinese Materia Medica
2021;46(11):2783-2787
- CountryChina
- Language:Chinese
-
Abstract:
Root rot was occurred widely in the production area of Rehmannia glutinosa, and which result in serious influence on the yield and quality of R. glutinosa. In the present work, a new phytopathogen was isolated from roots with root rot symptom in the production area of R. glutinosa. The colony of the pathogen growing on PDA medium was gray-black, the structure of hyphae was compact, the aerial hyphae was less developed, and the back of the colony was black. The hyphae of the pathogen were uneven in size, about 2 to 3 μm in diameter and twined with each other, the conidia of the pathogen were small, nearly round and about 1 μm in diameter. The healthy roots of R. glutinosa were inoculated with the pathogen in vitro, black-brown rot was observed at the inoculate sites after a few days' incubation. The rhizosphere soil of healthy R. glutinosa seedlings were inoculated in vivo, the leaves were wilted and the roots were black-brown rotted after several days' normal culture, the symptoms were consistent with those observed in the field. The genomic DNA of the pathogen was amplified by fungus rDNA-ITS universal primer ITS1/ITS4 and homologous analyzed, the pathogen was in a branch with Heterophoma sp., Phoma sp., P. novae-verbascicola and P. herbarum with the nuclear acid homology of 99.21% to 99.43%. The pathogen shown 97.00% to 98.02% nuclear acid homology with H. verbascicola, H. novae-verbascicola, H. poolensis, P. herbarum, H. sylvatica, H. verbascicola and H. verbasci-densiflori when amplified by the tub2 gene special primer Btub2 fd/Btub4 rd, and H. novae-verbascicola was the highest. The pathogen was in a branch with H. novae-verbascicola when amplified by the lsu gene special primer LR0 R/LR7. Based on the morphological characteristics, nucleotide sequence analysis and Koch's test results, the isolated pathogen causing root rot of R. glutinosa was identified as H. novae-verbascicola. This study is of great significance for the further theoretical research on root rot of R. glutinosa and root rot control in field.
