• Research in Plant Disease
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• v.20 no.4
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• pp.275-282
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• 2014

The occurrence of post-harvest diseases and their pathogens in 'Campbell Early' which is the most produced grape in Korea was investigated. The 'Campbell Early' grapes produced in 3 main grape-producing areas were stored in a cold room ($0-4^{\circ}C$) for 2 weeks then at room temperature for 4 weeks prior to investigation. The major post-harvest diseases occurred were gray mold, blue mold, ripe rot, new decay 1, and new decay 2. Pathogens isolated from the symptoms were identified as Botrytis cinerea for gray mold, Penicillium sclerotiorum for blue mold and Collectrichum acutatum for ripe rot. Pathogens for new decay 1 and new decay 2 were not identified yet. Incidences of new decay 1 and new decay 2 were much higher than the other 3 decays in all grapes produced from 3 areas. Gray mold and blue mold occurred at much lower frequencies than these two decays, and ripe rot occurred least.

• The Plant Pathology Journal
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• v.17 no.6
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• pp.364.2-364
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• 2001

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2005.04a
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• pp.87.1-87.1
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• 2005

• Mycobiology
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• v.48 no.5
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• pp.423-426
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• 2020

Cypripedium japonicum is known to be the indigenous plant to Korea, Japan, and China. However, C. japonicum represents the most critically endangered plant species in South Korea. The plant is esthetically pleasing due to its flower, which is larger than any other orchidaceous species. Disease symptoms relating to gray mold were observed on C. japonicum in May 2019. The suspected pathogen was successfully isolated from the symptomatic leaf tissue and conducted a pure culture of the fungi. The conidia formed consisted of a colorless or light brown single cell, which was either egg or oval-shaped with a size of 7.1 to 13.4 × 5.2 to 8.6 ㎛. Molecular phylogenetic relationship analysis was also confirmed that the pathogen concerned belonging to the family of Botrytis cinerea. Therefore, the findings confirmed that the pathogen isolated from C. japonicum was consistent with the unique properties of B. cinerea.

• The Korean Journal of Pesticide Science
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• v.16 no.4
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• pp.364-368
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• 2012

In vivo experiments were carried out to investigate the effect of microbial agents on tomato disease occurrences in a sustainable tomato farm in Gong-ju, Chung-nam during 2 years (2010-2011). Two kind of commercial microbial agents (EXTN-1 and Cillus suspension concentrate) and 2 kind of microbial agents (Bacillus subtilis strain 'B4' and 'B17') developing by National academy of agricultural science were used in this study. In the 1st experimental year, the microbial agents were sprayed on leaves for 2-4 times at 1-2 weeks interval from 3 weeks after transplanting, and then disease occurrence were observed. As a result, the control efficacies of commercial EXTN-1 and Cillus suspension concentrate (SC) against gray mold were 59.6% and 50.5% in the treatment of 4 times foliar application at 1 week interval from 3 weeks after transplanting, and the control efficacy of commercial EXTN-1 SC against gray mold was 55.4% in the treatment of 3 times foliar application at 1 week interval from 4 weeks after transplanting. However, the control efficacies of EXTN-1 and Cillus SC were not enough for tomato crop protection against powdery mildew. In the 2nd experimental year, the microbial agents were treated following by the planned combination schedule of transplanting stage drip-watering, early stage root irrigation and early blooming stage foliar application. The control efficacies of EXTN-1 SC and B17 treatment following by transplanting stage drip-watering, 2 times root irrigation at 2 weeks interval root irrigation and 4 times foliar application at 1 weeks interval for gray mold management were 57.0 and 55.1%, respectively. In the case of same treatment for gray mold management mentioned at above, the control efficacies of EXTN-1 SC, B4 and B17 treatment for powdery mildew management were 50.5, 51.3 and 52.5%, respectively.

• Research in Plant Disease
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• v.15 no.3
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• pp.222-229
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• 2009

A Pseudomonas strain SG3 producing biosurfactant and showing antifungal and insecticidal activities was isolated from agricultural soil severely contaminated with machine oils. The antagonistic bacterium inhibited mycelial growth of all of the tested fungal pathogens. The fermentation broth of SG3 also effectively suppressed the development of various plant diseases including rice blast, tomato gray mold, tomato late blight, wheat leaf rust, barley powdery mildew and red pepper anthracnose. An antifungal substance was isolated from the fermentation broth of SG3 by ethyl acetate partitioning, silica gel column chromatography and preparative HPLC under the guide of bioassay. The chemical structure of the antifungal substance was determined to be rhamnolipid B by mass and NMR spectral analyses. The antifungal biosurfactant showed a potent in vivo antifungal activity against gray mold and late blight on tomato plants. In addition, rhamnolipid B inhibited mycelial growth of B. cinerea causing tomato gray mold and zoospore germination and mycelial growth of P. infestans causing tomato late blight. Pseudomonas sp. SG3 producing rhamnolipid B could be used as a new biocontrol agent for the control of plant diseases occurring on tomato plants.

• Research in Plant Disease
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• v.16 no.3
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• pp.316-319
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• 2010

The gray mold disease occurred on tuberous roots of yacon in storage facilities in Gangneung, Korea, in March 2010. Symptoms typically appeared as in the form of dark brown discoloration on the surface of tuberous roots and water-soaked brown lesions in cross sections of the affected portions. A total of five isolates of Botrytis sp. were obtained from the symptomatic portions. All isolates on potato-dextrose agar (PDA) produced abundant conidia which were pale brown, one-celled, mostly ellipsoid or ovoid in shape and $8.2{\sim}14.8{\times}6.5{\sim}9.9\;{\mu}m$ in size. Large numbers of round to irregular, smooth, black, hard sclerotia were produced on PDA over time. The optimal temperature for mycelial growth and sclerotia formation of the fungal isolates was $20^{\circ}C$. On the basis of morphological and cultural characteristics, all the fungal isolates were identified as Botrytis cinerea. Pathogenicity test on host plants showed that the fungus could infect not only tuberous roots but also leaves and petioles of yacon. This is the first report on gray mold of yacon (Smallanthus sonchifolius) caused by Botrytis cinerea in Korea.

• Research in Plant Disease
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• v.10 no.3
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• pp.159-166
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• 2004

This study were carried out to identify pathogens and determine the seasonal occurrence and chemical control of safflower (Carthamus tinctorius) diseases from 2000 to 2002 in Gyengbuk province, Korea. Major diseases of safflower were, anthracnose caused by Colletotricum acutatum in open field, and gray mold by Botrytis cinerea in rain sheltered plastic house. Other diseases occurred were powdery mildew caused by Sphaerotheca fuliginea, collar rot by Sclerotium rolfsii, leaf spot by Alternaria carthami and A. alternata, rust by Puccinia carthami, root-rot and stem-rot by Phytophthora cactorum, root-rot and wilt by Fusarium oxysporum and damping-off by Pythium ultimum. Seasonal occurrence of anthracnose on safflower has begun from late April, and increased until harvesting, especially rapid increased after rainfall during stem elongation season that is from May to June. In open fields, maximum incidence of anthracnose was 67 ％ in late July. But in rain-sheltered plastic house, it was very low, about 5％ in July. Gray mold caused by Botrytis cinerea was most important disease in rain-sheltered plastic house cultivation. Maximum incidence of gray mold on floral head was 27.4％, whereas other diseases occurred below 1 ％. In the test of the chemical control of the safflower anthracnose, metiram WP, carbendazim$.$kasugamycin WP and iminoctadintris$.$thiram WP were the highest controlling chemicals. In chemical control of gray mold, iminoctadintris$.$thiram WP, fluazinam WP and iprodion WP showed highest controlling effects.

• Proceedings of the Korea Contents Association Conference
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• 2018.05a
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• pp.459-460
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• 2018

In this paper, we present a data augmentation method that generates synthetic plant disease images using Generative Adversarial Networks (GANs). We propose a training scheme that first uses classical data augmentation techniques to enlarge the training set and then further enlarges the data size and its diversity by applying GAN techniques for synthetic data augmentation. Our method is demonstrated on a limited dataset of 2789 images of tomato plant diseases (Gray mold, Canker, Leaf mold, Plague, Leaf miner, Whitefly etc.).

• Research in Plant Disease
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• v.21 no.3
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• pp.193-200
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• 2015

Gray mold caused by Botrytis cinerea is one of the most important postharvest fungal pathogens of cut flowers. Here, gamma irradiation, an alternative for phytosanitary purposes, and sodium dichloroisocyanurate (NaDCC) were used to control B. cinerea in a cut chrysanthemum (Chrysanthemum morifolium Ramat.) cultivar, 'Baekma', one of the cultivars susceptible to B. cinerea. Spore germination and mycelium growth of B. cinerea were inhibited by gamma irradiation in an inversely dose-dependent manner. A dose of 4 kGy completely inhibited the mycelium growth of B. cinerea. A significant change in flower quality (physical properties) on chrysanthemum was shown from gamma irradiation at over 0.2 kGy (p<0.05). Therefore, in this study, the integration of gamma ray (below 0.2 kGy) and NaDCC, an eco-friendly form of chlorine, was investigated to control the disease with low dose of gamma irradiation dose. Interestingly, the gamma irradiated flowers showed more disease severity than the non-irradiated flowers. The combined treatment of gamma irradiation and NaDCC does not affect the severity of the fungal disease, whereas only 70 ppm of NaDCC treatment showed a significantly reduced severity. These results suggest that only chlorination treatment can be applied to control B. cinerea in cut chrysanthemum flowers.