• Mycobiology
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• v.43 no.2
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• pp.174-178
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• 2015

Fusarium wilt of zucchini in Jeonju, Korea, was first noticed in May 2013. Symptoms included wilting of the foliage, drying and withering of older leaves, and stunting of plants. Infected plants eventually died during growth. Based on morphological characteristics and phylogenetic analyses of the molecular markers (internal transcribed spacer rDNA and translation elongation factor $1{\alpha}$), the fungus was identified as Fusarium oxysporum. Pathogenicity of a representative isolate was demonstrated via artificial inoculation, and it satisfied Koch's postulates. To our knowledge, this is the first report of F. oxysporum causing wilt of zucchini in Korea.

• Mycobiology
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• v.45 no.2
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• pp.110-113
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• 2017

Severe root rot was observed in fields of cabbages (Brassica oleracea L.) in 2015 in China. Cardinal symptoms of this disease included root rot and wilting leaves. A fungus was isolated from diseased tissues consistently. Based on the morphological features and molecular analysis of the ITS-5.8S rDNA and D1/D2 domain of the 28S rRNA gene, it was identified as Plectosphaerella cucumerina. This is the first report of P. cucumerina causing cabbage root rot in China and the world.

• The Korean Journal of Mycology
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• v.47 no.4
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• pp.443-446
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• 2019

In 2017, wilting symptom was observed on seedlings of Anthurium andraeranum in Youngin, Korea. Brownish lesions with water soaking were developed on the stems and roots of the infected plants. The stems and leaves wilted and finally died. One fungal isolate was obtained in pure culture. Morphological features and nucleotide sequences of internal transcribed spacer rDNA and cytochrome oxidase subunit II mt DNA were analyzed. The results of this study indicated that the fungus is identified as Phytopythium vexans. Pathogenicity tests showed the isolate was pathogenic to the seedlings of A. andraeanum. To our knowledge, this is the first report of P. vexans causing stem rot on A. andraeanum in Korea.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.1
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• pp.23-26
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• 1985

This experiment was investigated on weight loss, vitamin C content, and its relationship to evaluate visual quality during spinach consignment from a viewpoint of consumer. Vitamin C content of spinach leaf, 35.38mg% fresh weight, was 3 times higher than those of stem. Under $20^{\circ}C$ of spinach consignment, the spinach was edible in a half day of unpackage and 3 days with package. However, under $10^{\circ}C$ of spinach consignment, it was good through 6-7 days with unpackged and 10 days with package. Weight and vitamin C content of stem and leaf in spinach during consignment were closely related to the temperature condition at $20^{\circ}C$ than at $10^{\circ}C$ in both of package and unpackage. The regression equation of relationship between loss(X) and vitamin C loss(Y) of spinach, during consignment with Package and unpackage at $20^{\circ}C$ and $10^{\circ}C$ was Y=21.30X+40.32(r=0.69.)

• Korean Journal Plant Pathology
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• v.10 no.3
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• pp.240-244
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• 1994

Watermelon plants grafted with the root-stock of wild-cucumber (Sicyos angulatus) were not infected by Fusarium oxysporum f.sp. niveum in pot inoculation and infected fields tests. Controlling efficacy of the root-stock grafting with S. angulatus on Fusarium wilt of watermelon was more excellent than that of the root-stock grafting with Lagenaria siceraria. The isolates of Fusarium oxysprum from cucurbitaceae plants had a certain host-specific pathogenicity, but they did not express the absolute one forma specialis-one host-plant phenomenon by the root dipping inoculation. The pathogenic isolates of Fusarium oxysproum from cucurbitaceae crops did not infect the root-stock plant such as S. angulatus, L. siceraria and Cucurbita ficifolia. The fast-wilting of watermelon caused by uncertain agents was observed in watermelon plant grafted with L. siceraria in the continuously cropping fields, but it was not observed in watermelon plants grafted with S. angulatus in the same fields.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.141-154
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• 2009

• Plant Disease and Agriculture
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• v.5 no.2
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• pp.115-118
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• 1999

A new bacterial disease was found on trees of peach(Prunus persica var. vulgaris Max) at Kumho Kyungbuk in April 1999. The disease usually occured on over wintered buds branchs and stems of the Cheon-Hong cultivar. The buds died without sprouting and the branches showed entire wilting Droplets of bacterial ooze was occasionally running down the surface of diseased plants under moist condition. Artificial needle prick inoculation with isolates obtained from branchs of naturally infected plants produced symptoms similar to those occuring under natural condition. On the basis of bacteriological characteristics and pathogenicity on the host plant of the organism the causal bacterium was identified as Xanthomonas arboricora pv. pruni and this disease was proposed to name "Bacterial branch blight of the peach tree"

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.735-737
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• 1998

A severely wilting of strawberry caused by a Phytophthora sp. has occurred houses after planting in vinyl-houses field at Ssanglim and Anlim areas Kyungbuk in Korea from October in 1997. Phytophthora sp. isolated from diseased tissues of the crown of strawberry. Browning rot of inner crown and root resulted in wilt and eventual death of the plant. The causal fungus was identified as Phytophthora cactorum. Sporangia were ovoid, conspicuously papillate, caducous and measured 30.0~56.6$\times$23.8~35.2 (av. 39.3~29.9) ${\mu}{\textrm}{m}$. Sexuality of the fungus was homothallic. Oogonia were sperical and 23.3~32.3 (av. 29.0) ${\mu}{\textrm}{m}$ in size. Most ahteridia were paragynous and measured av. 10.2~12.2 ${\mu}{\textrm}{m}$. Cardinal temperature for growth at minimum, optium, maximum were recorded at 7, 20~25, and 32$^{\circ}C$, respectively. The fungus show strong pathogenicity to strawberry. This is the first report of strawberry caused by Phytophthora cactorum in Korea.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.555-557
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• 1998

Occurrence of soft rots was observed on wasabi (Wasabia japonica Matsum) grown in Chuncheon and Pyengchang Kangwon province, Korea. The symptoms appeared on the wasabi root, which became mushy and black. This eventually resulted in wilting and death of the aboveground parts of the wasabi. The causal organism was isolated from the infected lesions and was identified as Erwinia carotovora subsp. carotovora based on the morphological, physiological and biochemical characteristics, and on the results of the Biolog program (Biolog Inc., U. S. A.). E. carotovora subsp. carotovora is the first described bacterium which causes bacterial soft rot on wasabi in Korea.

• The Plant Pathology Journal
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• v.30 no.3
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• pp.299-303
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• 2014

This study aims to isolate and identify the causal pathogen of tomato bacterial wilt in Egypt. In 2008, tomato plants showing typical symptoms of bacterial wilt disease with no foliar yellowing were observed in Minia, Assiut and Sohag governorates, Egypt. When cut stems of symptomatic plants were submerged in water, whitish ooze was evident and longitudinal sections showed a brown discoloration in the vascular tissues. Bacteria were isolated on triphenyl tetrazolium chloride medium and fifteen isolates shown typical morphological and cultural characteristics were confirmed as Ralstonia solanacearum biovar 2 race 1. Pathogenicity tests showed that all isolates proved to be pathogenic to tomato plants, varied from 52 to 97% wilting. This is the first report of R. solanacearum biovar 2 race 1 causing bacterial wilt in tomato crop in Egypt.