• Korean journal of applied entomology
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• v.18 no.1 s.38
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• pp.11-14
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• 1979

Spinaches showing dark green mosaic symptoms were used for identification of broad bean wilt virus. In host reaction test, that virus caused local lesions on the inoculated leaves and mosaic symptoms on upper leaves of Chenopodium amaranticolor, Chenopodium quinoa and Vicia faba, and developed mosaic symptoms on Physalis floridana, Spinacia oleracea, Nicotiana tabacum, (White burley, Bright yellow) Nicotiana glutinusa. In agar gel-diffusion test, the virus showed positive reaction with broad bean wilt virus antiserum. Spherical virus particles with size of 25nm in diameter were observed in electron microscope.

• The Korean Journal of Mycology
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• v.51 no.4
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• pp.397-403
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• 2023

Wilt symptoms were observed in basil (Ocimum basilicum) plants grown in a vinyl greenhouse located in Gokseong, Korea, during crop disease surveys conducted in August 2022. The symptoms appeared as wilting of the plants and brown to dark brown longitudinal streaks on the stems at or above the soil line. The disease incidence among the plants in the vinyl greenhouse was 5-20%. Six isolates of Fusarium sp. were obtained from stem lesions and identified as Fusarium oxysporum species complex based on their morphological characteristics. Among the isolates, two were used for phylogenetic analysis and pathogenicity test. Phylogenetic analysis revealed that these isolates belonged to F. oxysporum. Pathogenicity of the isolates was confirmed through artificial inoculation test. The symptoms induced by the isolates were similar to those observed in basil plants in the investigated vinyl greenhouse. This is the first report of F. oxysporum causing Fusarium wilt in basil in Korea.

• Korean Journal Plant Pathology
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• v.14 no.2
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• pp.188-190
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• 1998

Fusarium wilt of lisianthus occurred severely throughout all cultivation areas, especially in alpoine areas during summer season and the disease incidence was 5 to 30 percent in Korea. The major symptoms of the disease were wilt with chlorosis and water deficiency, stunted plants and scorched leaves. Severe symptoms appeared just after high temperature period around late August in Daekwallyong area. Whit and pale red colored mycelia were developed on stems of infected plants near the soil surface. The causal organism of Fusarium wilt of lisianthus was isolated and identified as Fusarium oxysporum f. sp. eustomae on the basis of pathogenic and cultural characteristics. The causal organism was reisolated from all infected and inoculated stems of plants. This is the first report referring to F. oxysporum f. sp. eustomae of lisianthus in Korea.

• Research in Plant Disease
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• v.27 no.4
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• pp.187-191
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• 2021

Wilt symptoms were frequently observed in Korean blackberry (Rubus coreanus) plants grown in farmers' fields located in Gochang and Jeongeup, Jeonbuk Province, Korea during disease surveys in July 2020. The disease occurred in 10 of the 13 fields surveyed in the two locations. The incidence of diseased plants in the fields was 5-80%. Seven isolates of Fusarium sp. were obtained from the diseased plants and examined for their morphological and molecular characteristics. All the isolates belonged to Fusarium oxysporum species complex based on the morphological characteristics but were identified as F. cugenangense based on the molecular characteristics. Two isolates of F. cugenangense were tested for pathogenicity on Korean blackberry plants by artificial inoculation. Pathogenicity of the two isolates on the plants was confirmed with the inoculation tests, which showed wilt symptoms similar to those observed in the diseased plants in the fields investigated. This is the first report of F. cugenangense causing Fusarium wilt in Korean blackberry.

• Mycobiology
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• v.51 no.3
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• pp.186-194
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• 2023

In July 2021, wilting symptoms were observed in adult and seedling hemp (Cannabis sativa L. cv. Cherry Blossom) plants grown in a greenhouse. As the disease progressed, yellowing and wilting symptoms on the leaves developed, resulting in whole plant death. In seedling plants, typical damping-off symptoms were observed. To identify the pathogen, the roots of diseased plants were sampled, surface sterilized, and cultured on potato dextrose agar (PDA) media. From the culture, 4 different fungal isolates were recovered and purely cultured. Each fungal isolate showed distinct growth shapes and color development on malt extract agar, oatmeal agar, sabouraud dextrose agar, and PDA media. Microscopic observation and molecular identification using ribosomal DNA internal transcribed spacer sequencing identified them as 3 Fusarium spp. and 1 Thielaviopsis paradoxa. Additional sequencing of elongation factor 1-alpha and b-tubulin regions of 3 Fusarium spp. revealed that 2 of them are Fusarium solani, and the other one is Fusarium proliferatum. To examine which isolate can act as a causal agent of wilt disease of hemp, each isolate was tested for their pathogenicity. In the pathogenicity test, F. solani AMCF1 and AMCF2, and F. proliferatum AMCF3, but not T. paradoxa AMCF4, were able to cause wilting disease in hemp seedlings. Therefore, we report that F. solani AMCF1 and AMCF2, and F. proliferatum AMCF3 as causal agents of Fusarium wilt of hemp plants. To our knowledge, this is the first report of the wilt disease of C. sativa L. caused by Fusarium spp. in Korea.

• The Plant Pathology Journal
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• v.23 no.1
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• pp.3-6
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• 2007

Chickpea wilt caused by Fusarium oxysporum f. sp. ciceris(FOC) is the most destructive disease in India. It is seed-borne as well as soil-borne pathogen. The role of seed-borne FOC in introducing and establishing wilt in FOC free soils is unknown. Using seeds of FOC infected chickpea cultivar K 850, we provided an evidence of establishing wilt disease in the FOC free soils within three crop cycles or seasons. In the first cycle, typical wilt symptoms were observed in 24 pots in 41 days after sowing. These 24 pots were used for second and third cycles without changing the soil. These 24 pots were sown with seeds collected from healthy plants of a susceptible cultivar JG 62, one seed per pot and development of wilt symptom was recorded. Wilt symptoms appeared in all the pots 26 days after sowing in second cycle and in 16 days after sowing in third cycle. On selective medium, all of the wilted plants yielded FOC in all the three cycles indicating that the mortality was due to wilt. FOC propagules on selective medium were 172, 1197, and 2280 $g^{-1}$ soil at the end of the first, second, and third cycles, respectively. These studies indicated that Fusarium wilt of chickpea is seed-borne and seeds harvested from wilted plants when mixed with healthy seeds can carry the wilt fungus to new areas and can establish the disease in the soil to economic threshold levels within three seasons.

• Korean Journal Plant Pathology
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• v.14 no.2
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• pp.103-108
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• 1998

A Pythium species was isolated from roots of lisianthus (Eustoma grandiflorum) showing wilt symptoms and reduced growth in a greenhouse at Ichon, Kyonggi-do in 1997. The Pythium species was identified as Pythium spinosum Sawada based on various mycological characteristics. The isolate was strongly pathogenic when inoculated to root of lisianthus plants in pots. The diseased plants showed typical symptoms of root and crown rot, resulting in reduced growth of roots and shoots, and consequently wilting of the above ground part of plants.

• Research in Plant Disease
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• v.16 no.3
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• pp.232-237
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• 2010

Tomato spotted wilt virus (TSWV) was occurred on the three vegetables of egg plant (Solanum melongena), whole radish (Raphanus acanthiformis) and sugar loaf (Cichorium intybus) at Anyang area infested with TSWV. Whole radish was produced the symptoms of necrotic spots on the leaves, and necrosis and malformation on the roots by TSWV. Egg plant was induced the symptoms of typical multiple ring spots on the leaves and necrotic rings on the fruits. Sugar loaf was infected severely with the typical symptoms of ring spots on the leaves and stunt. The three isolates of TSWV could infect locally on the indicator plants of Chenopodium amaranticolor, C. quinoa and Nicotiana debney, and systemically on N. glutinosa, N. benthamiana and Datura stramonium. Two TSWV isolates from egg plant and sugar loaf were very similar in virulence. However, the virulence of TSWV from whole radish was very different as local infection on 5 Nicotiana species including N. tabacum 'Xanthi NC'.

• 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.

• The Plant Pathology Journal
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• v.19 no.3
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• pp.184-187
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• 2003

Verticillium wilt was first observed in 2001 on potatoes (Solanum tuberosum) cv. Superior at Daegwallyong area, one of the major seed potato producing areas in Korea. The wilted potato plants showed typical symptoms including gradual yellowing and interveinal necrosis. There was discoloration in the vascular tissues of the infected stems which turned light brown. Fungal isolates from discolored vascular tissues were whitish to creamy with folding on potato dextrose agar medium, where they used to produce resting dark mycelia but no micro-sclerotia. Conidiophores were septate with side branches, swelled at the base, and arranged in a whorl. Conidia were 2.5-11.2$\times$2.0-4.5 $\mu\textrm{m}$ um in size and were borne in small clusters at the tips of phialides. Optimal temperature range for mycelial growth was $25-30^{\circ}C$. Based on these cultural and morphological characteristics, the fungus was identified as Verticillium albo-atrum Reink & Berth. Pathogenicity tests by root dipping method revealed that the fungus caused the same symptoms as observed in naturally infected potato plants. This is the first report of Verticillium wilt on potato caused by Verticillium albo-atrum in Korea.