• Plant Disease and Agriculture
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• v.5 no.2
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• pp.119-121
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• 1999

A destructive collar rot of safflower occurred severely research farm of at Kyongsangnam-do Agricultural Research and Extension Services in 1999. Incidence of the disease at 3 fields in Chinju was ranged from 21.6 to 34.2% Upper parts of infected stems were mostly blighted and white mycelia were found on the lesions. The same fungus was isolated consistently from the infected tissues and confirmed its pathogenecity to safflower. The causal fungus of collar rot disease was identified as Sclerotium rolfsii by the examination of colony type sclerotium formation and pathogenicity test. This fungus also causes stem rot crown rot wilt or blight on the safflower. This is the first report on the collar rot of safflower caused by Sclerotium rolfsii in Korea.

• Plant Disease and Agriculture
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• v.5 no.1
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• pp.61-63
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• 1999

Bacterial soft rot was observed on radish grown in Hongcheon, Kanwon-Do, Korea. The soft rot symptoms began as small water-soaked lesions. The water-soaked lesions enlarged rapidly in roots and produced a foul odor. When roots were affected in the field, the shoots also became infected and watery, causing infected plants to wilt, disorganize, and die. The causal organism was isolated from the lesions, and the identified as Erwinia chrysanthemi based on the morphological, physiological and biochemical characteristics. E. chrysanthemi is first described bacterium which causes bacterial soft rot on radish in Korea.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.1
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• pp.79-82
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• 2012

Blossom-end rot is probably the most recognizable Ca deficiency that affects fruit production including pepper. We investigated the induction of blossom-end rot during the period of rapid vegetative growth and fruit setting, and the effect of Ca fertilization on the suppression of blossom-end rot in pepper plants grown in a plastic-film house. During the first fruit setting period, more than 60% of pepper fruits larger than 8 cm showed the symptoms of blossom-end rot. Under the condition of transpiration occurring at a much faster rate, growing leaves of pepper plants could be the greater sinks for Ca than developing fruits. The incidence of blossom-end rot was significantly decreased after two weeks of Ca fertigation. Calcium application during the rapid vegetative growth and fruit setting period could be suggested as a preventive step to overcome the local Ca deficiency inducing blossom-end rot of pepper fruits.

• Journal of the Korean Wood Science and Technology
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• v.42 no.2
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• pp.214-221
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• 2014

The deterioration in wood by the brown-rot fungus (Fomitopsispalustris) and the white-rot fungus (Trametesversicolor) were measured using ultrasonic velocity. Those were used for the decay exposure and 4 wood species of wood as the test specimens, Pinusdensiflora, Larixkaempferi, Pinuskoraiensis and Pinusrigida, were chosen with both the brown- and white-rot culture petridish during 12 weeks. After 12 weeks, the decrease rate of ultrasonic velocity was measured at 10~15%. In both brown- and white-rot exposure experiments, P. rigida showed significant decrease in ultrasonic velocity (20%), L. kaempferi on the other hand did not show decrease in ultrasonic velocity. After the fungal exposure experiment, the inside of specimens was investigated by computer tomography (C/T). After C/T investigation, bending tests were performed.

• Animal cells and systems
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• v.9 no.1
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• pp.37-40
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• 2005

In okra Macrophomina phaseolina and Furasium verticilloides cause collar-rot, seedling-rot and other severe diseases at fruit maturing stages. These stages were located in all the components of the seeds. The seeds collected from seeds infected with Macrophomina phaseolina and Fusarium verticilloides revealed 100% infection. Such seeds resulted in pre- and post-emergence mortalities. Inoculated seeds also showed pre- and post-emergence death of the seedlings. The fungi seed-transmitted showed disease symptoms at different growth of okra plant. Fusarium verticilloides causes the wilt and Macrophomina phaseolina causes the collar-rot. Until now seed transmission of these fungi have not been studied. Hence, in the present study an attempt has been made to fill this lacunae.

• Mycobiology
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• v.31 no.3
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• pp.173-178
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• 2003

India has maximum genetic materials in early cauliflower, which grow in subtropical conditions. Different disease parameters like linear growth, maximum growth rate per day, AUDPC, apparent infection rate and percent diseased area were calculated in artificially inoculated plants. Apparent infection rate is not co-related with the black rot disease incidence and should never be considered during characterization of disease resistance and varietal screening. Based on the above disease parameters Kunwari-18, Phool Gobhi Kunwari, Kataki-7 and BT-10-2 were selected as moderately resistance to black rot in early cauliflower. These lines can be used for black rot prone area and also for black rot disease improvement programme. Considering the qualitative and quantitative parameters, slow rotting resistance cauliflower lines are selected as such for cultivation and would be best suited in integrated disease programme.

• Mycobiology
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• v.42 no.4
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• pp.409-411
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• 2014

In March 2014, a kohlrabi stem rot sample was collected from the cold storage room of Daegwallyong Horticultural Cooperative, Korea. White and fuzzy mycelial growth was observed on the stem, symptomatic of stem rot disease. The pathogen was isolated from the infected stem and cultured on potato dextrose agar for further fungal morphological observation and to confirm its pathogenicity, according to Koch's postulates. Morphological data, pathogenicity test results, and rDNA sequences of internal transcribed spacer regions (ITS 1 and 4) showed that the postharvest stem rot of kohlrabi was caused by Sclerotinia sclerotiorum. This is the first report of postharvest stem rot of kohlrabi in Korea.

• Journal of Microbiology and Biotechnology
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• v.29 no.5
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• pp.809-812
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• 2019

Bacterial strains that improve mycelial morphology and growth of white-rot fungi in liquid medium could enhance the impact of white-rot fungi towards lesser recovery of neonicotinoids when cocultured. This was demonstrated by the recovery of clothianidin and acetamiprid from cocultures of the white-rot fungus Phlebia brevispora strains with two mycelial-growth-promoting bacteria, Enterobacter sp. TN3W-14 and Pseudomonas sp. TN3W-8. Clothianidin recovery from cocultures of white-rot fungi and bacteria was over 40% lower than that from axenic microbial cultures and mixed-bacterial cultures. About 20% less acetamiprid was equally recovered from both TMIC33929+TN3W-14 cocultures and mixed-bacterial cultures than from axenic fungal and bacterial cultures.

• The Korean Journal of Mycology
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• v.50 no.2
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• pp.143-147
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• 2022

Sclerotinia rot symptoms were observed in stringy stonecrop (Sedum sarmentosum) plants growing in vinyl greenhouses in Yeoju and Icheon, Gyeonggi Province, Korea, during disease surveys in spring 2019 and 2020. The initial symptoms were soft rot on stems and leaves at or above the soil line. Furthermore, the symptoms progressed upwards, and the infected plant parts exhibited white to grayish-yellow discoloration. The infestation of diseased plants in the vinyl greenhouses was 1-5% at the two locations examined. Eight isolates of Sclerotinia sp. were obtained from lesions of the diseased plants. The isolates were identified as Sclerotinia sclerotiorum based on their morphological and molecular characteristics. In addition, artificial inoculation tested three isolates of S. sclerotiorum for pathogenicity on stringy stonecrop plants. All the tested isolates caused Sclerotinia rot symptoms in the inoculated plants. The symptoms were similar to those observed in plants from the vinyl greenhouses investigated. This study is the first report of S. sclerotiorum causing Sclerotinia rot in stringy stonecrop.

• Mycobiology
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• v.51 no.5
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• pp.313-319
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• 2023

During disease surveys of Angelica acutiloba plants in Korea, leaf spot symptoms were observed in a field in Andong in July 2019, and stem rot symptoms in vinyl greenhouses in Yangpyeong in April 2020. Incidence of leaf spot and stem rot of the plants ranged from 10 to 20% and 5 to 30%, respectively. Morphological and cultural characteristics of fungal isolates from the leaf spot and stem rot symptoms fitted into those of the genus Phoma. Molecular phylogenetic analyses of two single-spore isolates from the symptoms using concatenated sequences of LSU, ITS, TUB2, and RPB2 genes authenticated an independent cluster from other Didymella (anamorph: Phoma) species. Moreover, the isolates showed different morphological and cultural characteristics in comparison to closely related Didymella species. These discoveries confirmed the novelty of the isolates. Pathogenicity of the novel Didymella species isolates was substantiated on leaves and stems of A. acutiloba through artificial inoculation. Thus, this study reveals that Didymella acutilobae sp. nov. causes leaf spot and stem rot in Angelica acutiloba.