• The Korean Journal of Pesticide Science
• /
• v.21 no.1
• /
• pp.90-96
• /
• 2017

Gray mold disease, cause by Botrytis cinerea, occurs severe damage on varieties of fruit and vegetable production, and have no a critical control method. In case of chemicals control, it is a trigger emergence of drug resistance strains due to using them continuously. In addition, the pathogen is difficult to control naturally because it is possible to survive regardless of host status. In this study, microorganisms were isolated from tomato flower and hive samples and in order to select suitable microbial control agents for tomato gray mold disease. During six-months study, we isolated 1,004 isolates from flower and 925 isolates from pollinator hive samples. Among them, 6 strains were selected based on result of antifungal activity test. The selected strains showed not only strong antifungal activity against gray mold pathogen, but also cellulase and protease enzyme activities. The selected strains were identified as Paenibacillus polymyxa. In plant assay, P. polymyxa prevented the gray mold disease occurrence near 75%.

• Journal of Life Science
• /
• v.11 no.3
• /
• pp.242-247
• /
• 2001

Botrytis cinerea E12 was isolated from the leaves, flowers and fruits of eggplant in the greenhouse in Halrim, Kimhae and Dejeo, Pusan. The leaves infected with the pathogen were appeared initially brown-color, small gray spots at the edge, and finally fall down. The fruit was showed the symptoms of circular or irregular shapes, followed by sunken. When the symptoms were developed, the conidia formed on the surface with gray color. To determine the pathogenicity of B. cinerea E12 against the eggplants, the conidia were suspended with 30% tomato juice, PDB and sterile water, respectively. The result showed that the conidial suspension with 30% tomato juice was highly effective on the pathogenicity as more than 90%. Moreover, the symptoms caused by inoculum were the same as those of wild-type pathogen.

• Journal of Bio-Environment Control
• /
• v.31 no.4
• /
• pp.376-383
• /
• 2022

The current study, which consisted of two independent studies (laboratory and greenhouse), was carried out to project the hypothesis fungi-spray scheduling for leaf mold and gray leaf spot in tomato, as well as to evaluate the effect of temperature and leaf wet duration on the effectiveness of different fungicides against these diseases. In the first experiment, tomato leaves were infected with 1 × 10⁴ conidia·mL^-1 and put in a dew chamber for 0 to 18 hours at 10 to 25℃ (Fulvia fulva) and 10 to 30℃ (Stemphylium lycopersici). In farm study, tomato plants were treated for 240 hours with diluted (1,000 times) 30% trimidazole, 50% polyoxin B, and 40% iminoctadine tris (Belkut) for protection of leaf mold, and 10% etridiazole + 55% thiophanate-methyl (Gajiran), and 15% tribasic copper sulfate (Sebinna) for protection of gray leaf spot. In laboratory test, leaf condensation on the leaves of tomato plants were emerged after 9 hrs. of incubation. In conclusion, the incidence degree of leaf mold and gray leaf spot disease on tomato plants shows that it is very closely related to formation of leaf condensation, therefore the incidence of leaf mold was greater at 20 and 15℃, while 25 and 20℃ enhanced the incidence of gray leaf spot. The incidence of leaf mold and gray leaf spot developed 20 days after inoculation, and the latency period was estimated to be 14-15 days. Trihumin fungicide had the maximum effectiveness up to 168 hours of fungicides at 12 hours of wet duration in leaf mold, whereas Gajiran fungicide had the highest control (93%) against gray leaf spot up to 144 hours. All the chemicals showed an around 30-50% decrease in effectiveness after 240 hours of treatment. The model predictions in present study could be help in timely, effective and ecofriendly management of leaf mold disease in tomato.

• Journal of Korea Foundry Society
• /
• v.15 no.3
• /
• pp.291-297
• /
• 1995

The mechanical properties and fracture toughness of permanent mold cast austempered gray cast iron(AGI) were compared to those of sand cast AGI. The iron was melted to eutectic composition in order to get better castability especially in permanent mold casting. Specimens prepared for tensile, impact and fracture toughness test were austenitized at $900^{\circ}C$ and austempered at $270^{\circ}C$ and $370^{\circ}C$ for 1 hour. The strength, impact and fracture toughness of permanent mold cast AGI were found to be superior to those of sand cast AGI. The maximum value of 836 MPA in tensile strength, was obtained at the austempering temperature of $270^{\circ}C$. But ductility of AGI was not improved by permanent mold casting.

• Mycobiology
• /
• v.39 no.1
• /
• pp.52-53
• /
• 2011

Gray mold of blueberry caused by Botrytis sp. is reported for the first time in Korea. A detailed description of the fungus is given, along with its rDNA internal transcribed spacer sequence. The fungus was identified as Botrytis cinerea based on mycological characteristics and molecular data.

• Agrochemical news magazine
• /
• v.25 no.1 s.194
• /
• pp.41-43
• /
• 2004

• The Korean Journal of Mycology
• /
• v.41 no.1
• /
• pp.38-41
• /
• 2013

In 2010 and 2011, gray mold was found on common fig (Ficus carica) fruit grown at the research field of Jeollabuk-do Agricultural Research and Extension Services, Korea. Gray mold symptoms on common fig fruit mainly occurred after harvest season until December. The typical symptom included brown water-soaked rot and fruit decay. The diseased fruit was covered by gray to brown colored conidiophore and conidia. The conidiophores were tree shape and measured $15-33{\times}2{\mu}m$. Conidia on conidiophore were ellipsoidal or lemon shape, colorless, single cell, and measured $7.3-14.6{\times}6.8-11.1{\mu}m$. The nucleotide sequences of the rDNA ITS region obtained from the pure culture of the gray mold on common fig were 100% similar to the sequences of the GenBank accession number HQ171052, EU519210, HQ171053, FN812726, HM849615, and EU563120 of B. cinerea isolates. In phylogenetic tree, the representative isolate was placed within same clade of B. cinerea. Based on the morphological characteristics and analysis of rDNA ITS sequence data, the fungus was identified as B. cinerea.

• Horticultural Science & Technology
• /
• v.34 no.4
• /
• pp.626-633
• /
• 2016

The objective of this study was to assess the effect of precooling and application of gaseous $ClO_2$ on the retention of freshness and quality of 'Maehyang' strawberry fruits intended for export. 'Maehyang' strawberry fruits (Fragaria ${\times}$ ananassa Duch.) were grown in commercial greenhouses and then harvested. Fruits of uniform and medium size at 60% ripeness were selected and assigned to one of four treatment groups: non-treatment (control), precooling only (PO), gaseous $ClO_2$ only (GCO) or precooling combined with gaseous $ClO_2$ (P + C). Weight loss was lowest in the PO treatment and greatest in the GCO treatment after export. Compared to the control and PO treatment groups, strawberry fruits in the GCO treatment group maintained high brightness and high chroma. Six days after shipping, fruits in the P + C treatment group had the highest soluble solids content, even as high as $10.05^{\circ}Brix$; the lowest value was observed in the PO treatment. The incidence rate of gray mold in strawberry fruits was 20% and 17% in the control and the PO treatment, respectively; in the GCO treatment, the incidence rate of gray mold amounted to 10%. No gray mold was observed in the P + C treatment group. These results indicate that gaseous $ClO_2$ treatment combined with precooling (P + C) was effective in maintaining the freshness of 'Maehyang' strawberry fruits intended for export from South Korea to Hong Kong.

• The Plant Pathology Journal
• /
• v.26 no.2
• /
• pp.170-177
• /
• 2010

Bacillus licheniformis N1, previously developed as a biofungicide formulation N1E to control gray mold disease of plants, was investigated to study the bacterial traits that may be involved in its biological control activity. Two N1E based formulations, bacterial cell based formulation PN1E and culture supernatant based formulation SN1E, were evaluated for disease control activity against gray mold disease of tomato and strawberry plants. Neither PN1E nor SN1E was as effective as the original formulation N1E. Fractionation of antifungal compounds from the bacterial culture supernatant of B. licheniformis N1 indicated that two different cyclic lipopeptides were responsible for the antimicrobial activity of the N1 strain. These two purified compounds were identified as iturin A and surfactin by HPLC and LCMS. The purified lipopeptides were evaluated for plant disease control activity against seven plant diseases. Crude extracts and purified compounds applied at 500 ${\mu}g/ml$ concentration controlled tomato gray mold, tomato late blight and pepper anthracnose effectively with over 70% disease control value. While iturin showed broad spectrum activity against all tested plant diseases, the control activity by surfactin was limited to tomato gray mold, tomato late blight, and pepper anthracnose. Although antifungal compounds from B. licheniformis N1 exhibited disease control activity, our results suggested that bacterial cells present in the N1E formulation also contribute to the disease control activity together with the antifungal compounds.

• 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.