• Proceedings of the Korean Society of Plant Pathology Conference
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• 2000.10a
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• pp.55.1-55
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• 2000

• The Plant Pathology Journal
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• v.35 no.5
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• pp.498-507
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• 2019

Odontoglossum ringspot virus (ORSV) is a member of the genus Tobamovirus. It is one of the most prevalent viruses infecting orchids worldwide. Earlier studies reported the genetic variability of ORSV isolates from Korea and China. However, the evolutionary rate, timescale, and phylogeographical analyses of ORSV were unclear. Twenty-one coat protein (CP) gene sequences of ORSV were determined in this study, and used them together with 145 CP sequences obtained from GenBank to infer the genetic diversities, evolutionary rate, timescale and migration of ORSV populations. Evolutionary rate of ORSV populations was $1.25{\times}10^{-3}nucleotides/site/y$. The most recent common ancestors came from 30 year ago (95% confidence intervals, 26-40). Based on CP gene, ORSV migrated from mainland China and South Korea to Taiwan island, Germany, Australia, Singapore, and Indonesia, and it also circulated within east Asia. Our study is the first attempt to evaluate the evolutionary rates, timescales and migration dynamics of ORSV.

• The Plant Pathology Journal
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• v.35 no.1
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• pp.71-76
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• 2019

$SdhB^{P225F}$ and $SdhB^{H272R}$ mutations have been found associated with boscalid resistance in Botrytis cinerea from strawberry in Shanghai, China. For rapid detection of two mutations, tetra-primers were designed and optimized to gain the relatively high accuracy and specificity based on the ARMS-PCR technique, by which resistance can be identified with different lengths of products on agarose gels. The tetra-primer ARMS-PCR systems for $SdhB^{P225F}$ and $SdhB^{H272R}$ were validated by 9 SdhB-squenced strains repeatedly. Then, sensitivity of 30 more strains were also tested by the methods, which were accordant with genotypes by sequencing and the sensitivity of conidial germination to boscalid by 100%. Thus, the methods developed in this study are proved to be rapid, inexpensive, accurate and practical for resistance detection of Botrytis cinerea caused by $SdhB^{P225F}$ and $SdhB^{H272R}$ mutations.

• The Plant Pathology Journal
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• v.35 no.1
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• pp.11-18
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• 2019

Gaeumannomyces graminis var. tritici is a soil borne pathogenic fungus associated with wheat roots. The accurate quantification of gene expression during the process of infection might be helpful to understand the pathogenic molecular mechanism. However, this method requires suitable reference genes for transcript normalization. In this study, nine candidate reference genes were chosen, and the specificity of the primers were investigated by melting curves of PCR products. The expression stability of these nine candidates was determined with three programs-geNorm, Norm Finder, and Best Keeper. $TUB{\beta}$ was identified as the most stable reference gene. Furthermore, the exopolygalacturonase gene (ExoPG) was selected to verify the reliability of $TUB{\beta}$ expression. The expression profile of ExoPG assessed using $TUB{\beta}$ agreed with the results of digital gene expression analysis by RNA-Seq. This study is the first systematic exploration of the optimal reference genes in the infection process of Gaeumannomyces graminis var. tritici.

• Proceedings of the Korean Society of Crop Science Conference
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• 1987.06a
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• pp.48-49
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• 1987

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1999.10a
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• pp.34.1-34
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• 1999

• Mycobiology
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• v.46 no.2
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• pp.168-171
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• 2018

In 2016, a severe leaf spot disease was found on Iris ensata Thumb. in Nanjing, China. The symptom was elliptical, fusiform, or irregularly necrotic lesion surrounded by a yellow halo, from which a small-spored Alternaria species was isolated. The fungus was identified as Alternaria iridiaustralis based on morphological characteristics. The pathogenicity tests revealed that the fungus was the causal pathogen of the disease. Phylogenic analyses using sequences of ITS, gpd, endoPG, and RPB2 genes confirmed the morphological identification. This study is the first report of A. iridiaustralis causing leaf spots on I. ensata in China.

• Mycobiology
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• v.48 no.3
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• pp.233-239
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• 2020

A small-spored Alternaria was found from black spots of storaged Koerle pear (Pyrus sinkiangensis), one of the economically important fruit in Xinjiang province, China. The morphology is similar to A. limoniasperae but obviously different in secondary conidiophores and conidial septa. A phylogenetic analysis using sequence datasets of ITS, GAPDH, TEF1, RPB2, Alt a1, OPA10-2, and EndoPG genes revealed that it belonged to the Alternaria alternata complex group. Pathogenicity tests illustrated that the fungus was the causal pathogen of black spot on Koerle pear fruit.

• Mycobiology
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• v.49 no.3
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• pp.267-274
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• 2021

Two Diaporthe species isolated from fruit of Citrus sinensis in China were characterized based on morphology and multilocus phylogeny of ITS, tef1, and tub2 gene sequences. The phylogeny indicated that the two species match Diaporthe taoicola and D. siamensis. A critical examination of phenotypic characteristics confirmed the phylogenetic results. Diaporthe taoicola was morphologically characterized by producing Alpha conidia with tapering toward both ends. Meanwhile, D. siamensis produced cylindrical or ellipsoidal Alpha conidia with two oil drops. Pathogenicity tests revealed that both species were pathogenic to fruit of C. sinensis. To our knowledge, the two species were firstly reported on Citrus sinensis in China.

• The Plant Pathology Journal
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• v.36 no.6
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• pp.651-657
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• 2020

Lotus is one of the most important aquatic vegetables in China. Previously, we detected sweet potato latent virus from lotus (SPLV-lotus) and found that it has highly significant sequence diversity with SPLV-sweet potato isolates (SPLV-sp). Here, we developed serological methods for the detection of SPLV-lotus in Chinese lotus cultivation areas. Based on the high sensitivity of SPLV-lotus coat protein antiserum, rapid, sensitive and large-scale diagnosis methods of enzyme-linked immunosorbent assay (ELISA) and dot blot in lotus planting area were developed. The established ELISA and dot blot diagnostic methods can be used to detect SPLV-lotus from samples successfully. And our results also showed that the SPLV-lotus and sweet potato isolates appeared clearly distinction in serology. Our study provides a high-throughput, sensitive, and rapid diagnostic method based on serology that can detect SPLV on lotus, which is suggested to be included in viral disease management approach due to its good detection level.