1.A novel pathogenic Colletotrichum species for rhizome rot disease of Polygonatum kingianum.
Wei-Si MA ; Lan-Ping GUO ; Xin WANG ; Tie-Lin WANG ; Shi-Wu YAN ; Hang JIN ; Zhi-Hui ZHANG ; Bin YANG
China Journal of Chinese Materia Medica 2021;46(21):5606-5613
Rhizome rot disease is one of the main disease of planted Polygonatum kingianum. In this study, six strains of pathogenic fungus was isolated from P. kingianum samples with rhizome rot disease collected from six counties in Yunnan province. Its pathogenicity was confirmed by inoculation to healthy P. kingianum rhizome according to Koch's postulates. The colonies of the isolated fungi on potato dextrose agar(PDA) were orange with abundant crescentic conidia which were eseptate with a mean size of 19. 3-24. 9 μm×5. 2-5. 9 μm and a L/W ratio of 3. 4-4. 5. There was an oil ball in the center of the conidium. It's easy to see setae on PDA colony.The phylogenetic tree based on ITS, GAPDH, CHS-1, HIS3, ACT, and TUB2 sequences by maximum likelihood(ML) method indicated that the pathogenic fungus for P. kingianum rhizome rot disease was clustered into the clade of Colletotrichum spaethianum species complex, and was close to C. spaethianum. However, there were some differences in morphological and genetic characteristics between the pathogenic fungus and C. spaethianum. Therefore, the pathogenic fungus for rhizome rot disease of P. kingianum was identified as a new Colletotrichum species named C. kingianum. The disease spreads primarily due to the plantation of infected seedlings of P. kingianum. It is necessary to choose healthy seedlings and take rigorous disinfection measures for the disease prevention.
China
;
Colletotrichum/genetics*
;
Phylogeny
;
Polygonatum
;
Rhizome
2.Epitypification: should we epitypify?
Journal of Zhejiang University. Science. B 2008;9(10):842-846
Epitypification can solve many taxonomic problems and stabilize the understanding of species, genera, families or orders. The aim of this paper is to illustrate how to epitypify. A few examples where taxa have been epitypified are considered and the benefits and disadvantages of epitypification are discussed. We also outline some examples of taxa which need to be epitypified with reasons.
Colletotrichum
;
classification
;
genetics
;
DNA, Fungal
;
genetics
;
isolation & purification
;
Fungi
;
classification
;
genetics
;
Mycological Typing Techniques
;
methods
;
Phylogeny
3.Genetic diversity and antibacterial activity of endophytic fungi from Zanthoxylum nitidum.
Yong-Zhi HU ; Xin-Feng YANG ; Ya-Qin ZHOU ; Li-Ying YU ; Xiao-Ming TAN ; Li-Chun ZHAO ; Zhong-Heng SHI ; Shi-Yi HU
China Journal of Chinese Materia Medica 2021;46(13):3349-3355
In order to reveal the distribution and population characteristics of endophytic fungi from Zanthoxylum nitidum and the antibacterial potential,this study performed molecular identification and analyzed the genetic diversity and antibacterial activity of endophytic fungi from Z. nitidum in Guangxi. Through culture and molecular identification,35 strains,belonging to 15 genera,12 families,10 orders,4 classes,and 2 phyla,were isolated from various tissues of Z. nitidum,of which Colletotrichum and Fusarium were the dominant genera,respectively accounting for 20% of total strains. The diversity of endophytic fungi was significantly different among roots,stems,and leaves,as manifested by the significantly higher Shannon index( H') in stems( 1. 678) than in roots( 0. 882 1) and leaves( 0. 515 4). The antimicrobial activity analysis showed that 14. 28% of endophytic fungi inhibited at least one indicator pathogen. Among them,Fusarium sp. ZN-34 and Fusarium sp. ZN-26 separately demonstrated the strongest inhibitory effect on Escherichia coli and Staphylococcus aureus. In general,Fusarium sp. ZN-26 and Phialemoniopsis plurioloculosa ZN-35 were advantageous in suppressing the two bacteria owing to the broad spectrum and strong efficacy. In summary,Z. nitidum in Guangxi boasts rich endophytic fungi with the majority showing strong antibacterial activity,which can be used as candidates for the extraction and separation of basic antibacterial substances and the development of natural antibacterial agents.
Anti-Bacterial Agents/pharmacology*
;
Anti-Infective Agents
;
China
;
Colletotrichum
;
Endophytes/genetics*
;
Fungi/genetics*
;
Genetic Variation
;
Humans
;
Microbial Sensitivity Tests
;
Zanthoxylum
4.Chilli anthracnose disease caused by Colletotrichum species.
Po Po THAN ; Haryudian PRIHASTUTI ; Sitthisack PHOULIVONG ; Paul W J TAYLOR ; Kevin D HYDE
Journal of Zhejiang University. Science. B 2008;9(10):764-778
Anthracnose disease is one of the major economic constraints to chilli production worldwide, especially in tropical and subtropical regions. Accurate taxonomic information is necessary for effective disease control management. In the Colletotrichum patho-system, different Colletotrichum species can be associated with anthracnose of the same host. Little information is known concerning the interactions of the species associated with the chilli anthracnose although several Colletotrichum species have been reported as causal agents of chilli anthracnose disease worldwide. The ambiguous taxonomic status of Colletotrichum species has resulted in inaccurate identification which may cause practical problems in plant breeding and disease management. Although the management and control of anthracnose disease are still being extensively researched, commercial cultivars of Capsicum annuum that are resistant to the pathogens that cause chilli anthracnose have not yet been developed. This paper reviews the causal agents of chilli anthracnose, the disease cycle, conventional methods in identification of the pathogen and molecular approaches that have been used for the identification of Colletotrichum species. Pathogenetic variation and population structure of the causal agents of chilli anthracnose along with the current taxonomic status of Colletotrichum species are discussed. Future developments leading to the disease management strategies are suggested.
Capsicum
;
microbiology
;
Colletotrichum
;
classification
;
genetics
;
pathogenicity
;
Fungicides, Industrial
;
Pest Control, Biological
;
Plant Diseases
;
microbiology
;
Species Specificity
;
Virulence