• Research in Plant Disease
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• v.18 no.1
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• pp.57-61
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• 2012

In March 2010, grafted cucumber cultivated in the greenhouse showed a severe rot on crown resulting yellowing and wilting of the leaves. The symptoms of naturally infected plants showed dark brown, watersoaked lesions at the base of the stem. The fungus produced mass of white mycelium and yellow to orange spores in necrotic lesions on dead and dying plants. Fungus was isolated from rotted tissues of the crown and root. On the basis of morphological characteristics, ITS sequence and pathogenicity tests, the isolate was identified as Fusarium solani f. sp. cucurbitae. This is the first report of the crown and foot rot of grafted cucumber caused by F. solani f. sp. cucurbitae in Korea.

• Mycobiology
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• v.30 no.1
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• pp.51-54
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• 2002

This paper deals with the study on comparative efficacy and in vitro activity of cow urine and cow dung for controlling root rot disease of cucumber caused by Fusarium solani f. sp. cucurbitae Snyder & Hansen following slide germination and mycelial growth inhibition tests. Results showed that both germination of conidia and the percentage inhibition of mycelial growth decreased or suppressed and varied greatly with respect to different hour and days of incubation and kind of bio-matters. In between two bio-matters cow urine was found more effective than that of cow dung in conidial germination. No germination of conidia was recorded after one hour of incubation in any medium whereas in cow urine germination of conidia was not also observed even after 2 hours of incubation. After 7 hours of incubation out of 200 conidia of F. solani f. sp. cucurbitae, 28 in cow urine and 64 in cow dung were germinated while in control a total germinated conidia was 185. In case of percentage inhibition of conidial germination the highest percentage(100%) was recorded in cow urine after 2 hours of incubation followed by 3 hours(96.0%), 4 hours(91.0%) and 6 hours(89.4%). During the test on inhibition of mycelial growth, the highest percentage(62.8%) was recorded in cow urine potato dextrose agar(CUPDA) medium tested after 4 days of incubation, followed by 3 days(60.5%), 5 days(56.5%) and 2 days(55.0%). In this test cow dung potato dextrose agar(CDPDA) had less efficacy in suppression of the percentage inhibition of mycelial growth.

• The Plant Pathology Journal
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• v.26 no.4
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• pp.409-416
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• 2010

Fusarium species, a large group of plant pathogens, potentially pose quarantine concerns worldwide. Here, we focus on the development of a method for detecting four Fusarium species in quarantined plants in Korea: F. solani f. sp. cucurbitae, F. stilboides, F. redolens, and F. semitectum var. majus. Species-specific primers were designed from the nucleotide sequences of either the translation elongation factor-1 alpha (TEF1) gene or RNA polymerase II subunit (RPB2) gene. Two different primer sets derived from TEF1, all specific to F. solani f. sp. cucurbitae, were able to differentiate the two races (1 and 2) of this species. A set of nested primers for each race was designed to confirm the PCR results. Similarly, two primer sets derived from RPB2 successfully amplified specific fragments from five F. stilboides isolates grouped within a single phylogenetic clade. A specific TEF1 primer set amplified a DNA fragment from only four of the 12 F. redolens strains examined, which were grouped within a single phylogenetic clade. All of the F. semitectum var. majus isolates could be specifically detected with a single RPB2 primer set. The specificity of the primer sets developed here was confirmed using a total of 130 Fusarium isolates.