• Mycobiology
• /
• v.42 no.3
• /
• pp.262-268
• /
• 2014

Several postharvest diseases of table grapes (Vitis vinifera) occur during storage, and gray mold rot is a particularly severe disease because the causal agent, Botrytis cinerea, grows at temperatures as low as $0^{\circ}C$. Other postharvest diseases, such as those caused by Penicillium spp. and Aspergillus spp., also often lead to deterioration in the quality of table grapes after harvest. The use of plant essential oils such as thymol and linalool, to reduce postharvest diseases in several kinds of fruits, including table grapes and oranges, has received much attention in European countries. However, to the best of our knowledge there has been no report of the use of thymol fumigation to control gray mold in table grapes in Korea. Thymol ($30{\mu}g/mL$) and linalool ($120{\mu}g/mL$) significantly inhibited mycelial growth and conidia germination of B. cinerea. The occurrence rate of gray mold rot of B. cinerea and other unknown fungi was significantly reduced by fumigation with $30{\mu}g/mL$ thymol in several table grape cultivars, such as Campbell early, Muscat Bailey A, Sheridan, and Geobong. In this study, fumigation with $30{\mu}g/mL$ thymol, had no influence on the sugar content and hardness of grapes, but reduced fungal infection significantly. This suggests that $30{\mu}g/mL$ thymol could be utilized to reduce deterioration of grapes due to gray mold and other fungal infections during long-term storage.

• Research in Plant Disease
• /
• v.18 no.3
• /
• pp.255-258
• /
• 2012

In September 2011, black leaf mold caused by Pseudocercospora fuligena occurred on tomato plants growing in protected cultivation conditions in Boryong and Buyeo, Chungnam Province, Korea. Symptoms of the disease initially appeared as foliar chlorotic spots on upper leaf surfaces, turned light brown and then black on lower leaf surfaces as the fungus sporulates profusely. The causal fungus was isolated from the diseased plants and identified as P. fuligena based on morphological characteristics. Pathogenicity of the fungus was proved by artificial inoculation in the green house. This is the first report of the occurrence of black leaf mold of tomato caused by P. fuligena in Korea.

• The Korean Journal of Mycology
• /
• v.33 no.2
• /
• pp.89-91
• /
• 2005

In April of 2003 to 2004, the gray mold disease caused by Botrytis cinerea on Hypericum ascyron was occurred in the exhibition field of Gyeongsangnam-do Agricultural Research and Extension Services, at Hamyang-gun in Korea. The disease symptoms were started with water-soaking lesions in stem and the infected plants became withered, discolored and died. The conidia and mycelia of the pathogen appeared on stems of infected plants. The conidia were 1-celled and mostly ellipsoid or ovoid in shape and their color was light gray. The size of conidia was $4{\sim}16\;{\times}\;3{\sim}8\;{\mu}m$ and that of conidiophores was $12{\sim}26\;{\mu}m$ respectively. The pathogen formed sclerotia abundantly on potato-dextrose agar. The optimum temperature for sclerotial formation was $20^{\circ}C$. Pathogenicity of the causal organism was proved according to Koch's postulate. The causal organism was identified as Botrytis cinerea based on mycological characteristics. This is the first report on gray mold of H. ascyron caused by B. cinerea in Korea.

• Research in Plant Disease
• /
• v.13 no.3
• /
• pp.216-219
• /
• 2007

Gray mold caused by Botrytis cinerea occurred on Prunus mume Sieb. & Zucc. in an experimetal orchard of Gyeongsangnam-do Agricultural Research and Extension Services in Korea from 2005 to 2007. The symptoms usually started with water-soaking lesions and hollow depression on the fruit surface. The conidia of the pathogen appeared on the surface fruits. The conidia were one celled and mostly ellipsoid or ovoid in shape and were colorless or pale brown in color. The conidia were $6{\sim}17{\times}4{\sim}10{\mu}m$ in size and conidiophores were $15{\sim}30{\mu}m$ in length. The sclerotial formed abundantly on potato-dextrose agar, They were flat or irregular in shape and black in color The optimum temperature for sclerotial formation was $20^{\circ}C$. On the basis of mycological characteristics and pathogenicity test on host plants, the fungus was identified as Botrytis cinerea Persoon: Fries. This is the first report on gray mold of P. mume caused by B. cinerea by in Korea.

• Research in Plant Disease
• /
• v.12 no.3
• /
• pp.287-289
• /
• 2006

Since 2004, a gray mold on Aerides japonicum Lindenb. & Reichb. caused by Botrytis cinerea occurred in a few greenhouses at Goseong and Tongyeong, Gyeongnam, Korea. The disease mainly started on the basal part of leaves, and often lead to severe rots of whole plant. Abundant grayish mycelia and conidial mats were visible on the lesions under a humid conditions. The light gray conidia were one celled and mostly ellipsoid or ovoid in shape. The conidia were $6{\sim}21{\times}4{\sim}13{\mu}m$ in size and conidiophores were $15{\sim}34{\mu}m$ in length. The fungus formed abundant sclerotia on potato-dextrose agar after 18 days incubation at $20^{\circ}C$. The fungus was identified as Botrytis cinerea Persoon: Fries. based on its pathogenicity and mycological characteristics examined in this study. This is the first report of gray mold of Aerides japonicum caused by B. cinerea in Korea.

• Research in Plant Disease
• /
• v.12 no.1
• /
• pp.58-61
• /
• 2006

Ggray mold caused by Botrytis cinerea occurred on Balsam pear (Momordica charantia) at Daesan-myon, Changwon city, Gyeongnam province in Korea from 2004 to 2006. The disease symptoms usually started with water-soaking lesions on the fruits tip and stem, and then the infected plants became withered and eventually died. The conidia of the pathogen appeared on the surface of fruit and stem of infected plants. The conidia were one celled and mostly ellipsoid or ovoid in shape and were light gray in color, The conidia were $6{\sim}20X4{\sim}12{\mu}m$ in size and conidiophores were $14{\sim}30{\mu}m$ in length. The sclerotia formed abundantly on potato-dextrose agar 18 days after incubation. The optimum temperature for sclerotial formation was $20^{\circ}C$. Pathogenicity of the causal organism was proved according to Koch,s postulates. The causal organism was identified as Botrytis cinerea Persoon: Fries based on the mycological characteristics. This is the first report on gray mold of M. charantia caused by B. cinerea in Korea.

• The Korean Journal of Mycology
• /
• v.34 no.2
• /
• pp.122-124
• /
• 2006

In March of 2005, gray mold disease caused by Botrytis cinereu on Stachys sieboldii Miq. was occurred in the mud cellar storage of Gyeongsangnam-do Agricultural Research and Extension Services, Korea. The symptoms started with water-soaked and rotten in the tubers. The conidia were one celled and mostly ellipsoid or ovoid in shape and light gray in color. The conidia were $5{\sim}16{\times}4{\sim}12{\mu}m$ in size and the conidiophores were $14{\sim}30{\mu}m$ in length. The pathogen formed conidia and sclerotia abundantly on PDA. The optimal temperature for mycelial growth and sclelotia formation was $20^{\circ}C$. On the basis of symptom, mycological characteristics and pathogenicity test on host plants, the fungus was identified as Botrytis cinerea Persoon: Fries. This is the first report on gray mold of S. sieboldii caused by B. cinerea in Korea.

• Mycobiology
• /
• v.48 no.5
• /
• pp.427-430
• /
• 2020

Ganoderma lingzhi is a well-known source of natural fungal medicines which has been given for the treatment of several diseases. China is one of the major commercial producers of Ganoderma mushroom worldwide. However, with the expansion of the commercial cultivation, the occurrence of the fungal diseases on G. lingzhi has also been increased. The green mold disease symptoms were observed in the cultivation base of G. lingzhi in Zuojia Town, Jilin City, Jilin Province, China, causing the basidiomes to be rotten and withered, and the green mycelium layer generated gradually. The pathogenicity tests showed the same symptoms as appeared naturally in Zuojia mushroom base. Morphology characters revealed conidia green, ellipsoid, globose, 2.56-4.83 × 2.09-4.22 ㎛, length-width ratio was 1.1-1.2 (n = 10). Conidiophores trichoderma-like, often asymmetry, branches solitary, paired or in whorls of 3 phialides formed solitary, paired or in whorl, variable in shape, lageniform, sometimes ampulliform or subulate. While using molecular methodology, comparing with the sequences of Trichoderma hengshanicum from GenBank, the analyzed sequence showed 97.32% homology with the RPB2 sequences, 100% with the TEF1-a sequences. A fungus isolated from the diseased tissues was identified based on morphology and molecular studies as T. hengshanicum. This is the first report of T. hengshanicum causing the green mold disease of G. lingzhi in China.

• Journal of Korea Foundry Society
• /
• v.17 no.2
• /
• pp.145-150
• /
• 1997

The striations parallel to the casting direction are the characteristic defects occurring during the unidirectional solidification of nonferrous metals such as pure Al and Sn. It has been known that the defects affect the recrystallization temperature as well as the mechanical and electrical properties of Al. However, it has not been still known about the effect of casting factors such as the casting speed, rod diameter of cast metals, and alloying elements on the occurrence of striations. In the present study, these casting factors affecting the occurrence of striation were investigated by adopting the quantitative examination of striations. Also, the relation between striation defects and feathery grain, which are very similar to the striation defects, was studied.

• Korean Journal of Environmental Biology
• /
• v.38 no.3
• /
• pp.486-495
• /
• 2020

We surveyed disease outbreak status that has recently become a problem in organic tomatoes and cucurbit in plastic greenhouse that were grown without spraying pesticides during the plastic greenhouse growing season of 2015 to 2019. It was found that the incidence of leaf mold, tomato spotted wilt virus, and tomato chlorosis virus disease was severe in tomato, and disease incidence of powdery mildew and zucchini yellow mosaic virus were severe in Cucurbit. The disease outbreak was found to be faster and more severe in crops grown in pesticide-free cultivation plastic greenhouses than in plastic greenhouses that are cultivated in general using pesticides. In particular, the occurrence of viral diseases mediated by thrips and aphids was found to be severely damaged. Therefore, in order to produce good organic products, it is important to effectively control pests, and in order to minimize the damage caused by disease, sanitation and physical blocking, and comprehensively utilize organic materials or microorganisms to prevent them.