• Korean Journal of Agricultural Science
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• v.46 no.1
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• pp.103-111
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• 2019

Gray mold caused by Botrytis cinerea on strawberry plants is an economically significant disease in Korea. The rates for diseased fruits are high during the strawberry harvesting period from December to February, especially in hydroponic cultivation. This study assessed the effect of the nitrogen type in the soil culture and the electrical conductivity (EC) of the nutrient solution in a hydroponic culture on the gray mold incidence in 'Seolhyang' strawberry plants. The nitrogen sources assayed included calcium nitrate tetrahydrate (CN4), calcium nitrate decahydrate (CN10), ammonium sulfate (AS), and commercial fertilizer 213 (213). The effect of the EC was tested at 0.5, 0.8, 1.0, and $1.5dS{\cdot}m^{-1}$. The occurrence of gray mold varied according to the nitrogen type. The disease incidence and nitrogen content for the main nitrogen type were higher compared to the non-treated control. The AS treatment showed the highest occurrence of tipburn and gray mold. The incidence of gray mold as well as the nitrogen and phosphorus content of the leaves increased as the EC level was increased. These results indicate that the incidence of gray mold in strawberry plants is related to the nitrogen content of the leaf and the EC of the nutrient solution.

• Korean Journal of Organic Agriculture
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• v.13 no.2
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• pp.161-173
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• 2005

This study was carried out to clarify the effects of antifungal bacterial strains isolated from the greenhouse soil grown strawberry plants on the growth inhibition of plant pathogen, gray mold (Botrytis cinerea) infected in strawberry plants in Damyang and Jangheung districts. Antagonistic bacterial strains were isolated and investigated into the antagonistic activity against gray mold. Screened ten bacterial strains which strongly inhibited Botrytis cinerea were isolated from the greenhouse grown strawberry plants, and the best antifungal microorganism designated as SB 143 was finally selected. Antifungal bacterial strain SB 143 was identified to be the genus Bacillus sp. based on the morphological and biochemical characterization. Bacillus sp. SB 143 showed 59.4% of antifungal activity against Botrytis cinerea. By the bacterialization of culture broth and heated filtrates of culture broth, Bacillus sp. SB 143 showed 93.1% and 32.1% of antagonistic activity against Botrytis cinerea.

• Research in Plant Disease
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• v.24 no.4
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• pp.257-264
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• 2018

Hydroponic strawberry culture system is increasing annually. Most of strawberry farmers use mulched bed in hydroponic culture and strawberry plants were transplanted in early September. After transplanting, Fusarium wilt caused by Fusarium oxysporum f. sp. fragariae and twospotted spider mite (TSSM), Tetranychus urticae, can increase their occurrence under high temperature condition. Therefore, we conducted for comparison occurrence of Fusarium wilt and TSSM on mulched with green polyethylene film and non-mulched bed. Occurrence of Fusarium wilt on mulched bed was started from early October and more increase than non-mulched bed. Damage rate of TSSM on mulched bed was shown higher than non-mulched bed. Temperature of substrate in mulched bed increased than non-mulched bed, but relative humidity near plants was decreased. As a result, use of non-mulched bed should be effective for reducing of Fusarium wilt and TSSM on strawberry plants.

• Plant Disease and Agriculture
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• v.5 no.1
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• pp.8-13
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• 1999

Twenty two different disease on strawberry have been reported in Korea. Their occurrence patterns were depended on the varieties cultivated. Fusarium wilt occurred seriously on var. Hokowase, a variety used for the fields or semi-forcing culture. In recent years, however, anthracnose occurred remarkably as the acreage of forcing culture increases. Consequently, anthracnose reduced the stand rate and yield of the strawberry. Average occurrence rate of anthracnose was 36.9% on major strawberry cropping areas. Nyoho and Akihime, which are popular varieties for the forcing culture, are considered to be susceptible, but Holiwase and Suhong are resistant against this disease. Colletotrichum gloeosporioides and Glomerella cingulata have been reported as casual agents for this disease in Korea. C. gloeosporoides was recently reported, but C. fragariae, known to be a strong pathogen in foreign countries, has bot been found yet in Korea. These two fungal pathogens showed significant differences in some characteristics such as major infection parts of plant and responses to temperatures as well as benomyl resistance. In addition, C. gloeosporioides is more pathogenic than G. cingulata. Because vinly sheltering is effective for control of anthracnose to protect water disposal of the pathogen during the seedling stages, it is strongly recommend to use this method in conjunction with integrated control programs.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.510-517
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• 2014

The purpose of this study was to analyze microbial hazards for cultivation environments and personal hygiene of strawberry and tomato farms at the growth and harvesting stage. Samples were collected from thirty strawberry farms and forty tomato farms located in Korea and tested for Staphylococcus aureus and Bacillus cereus. To investigate the change in the distribution of the S. aureus and B. cereus, a total of 4,284 samples including air born, soil or medium, mulching film, harvest basket, groves and irrigation water etc. were collected from eight strawberry farms and nine tomato farms for one year. As a result, total S. aureus and B. cereus in all samples were detected. Among the total bacteria of strawberry farms, S. aureus (glove: $0{\sim}2.1Log\;CFU/100cm^2$, harvest basket: $0{\sim}3.0Log\;CFU/100cm^2$, soil or culture media: 0~4.1 Log CFU/g, mulching film: $0{\sim}3.8Log\;CFU/100cm^2$), B. cereus (glove: $0{\sim}2.8Log\;CFU/100cm^2$, harvest basket: $0{\sim}4.8Log\;CFU/100cm^2$, soil or culture media: 0~5.3 Log CFU/g, mulching film: $0{\sim}4.5Log\;CFU/100cm^2$) were detected in all samples. The total bacteria of tomato farms, S. aureus (glove: $0{\sim}4.0Log\;CFU/100cm^2$, harvest basket: $0{\sim}5.0Log\;CFU/100cm^2$, soil or culture media: 0~6.1 Log CFU/g, mulching film: $0{\sim}4.0Log\;CFU/100cm^2$), B. cereus (glove: $0{\sim}4.0Log\;CFU/100cm^2$, harvest basket: $0{\sim}4.3Log\;CFU/100cm^2$, soil or culture media: 0~5.9 Log CFU/g, mulching film: $0{\sim}4.7Log\;CFU/100cm^2$) were detected in all samples. The contamination of S. aureus and B. cereus were detected in soil, mulching film and harvest basket from planting until harvest to processing, with the highest count recorded from the soil. But S. aureus and B. cereus were not detected in irrigation water samples. The incidence of S. aureus and B. cereus in hydroponics culture farm were less than those in soil culture. The amount of S. aureus and B. cereus detected in strawberry and tomato farms were less than the minimum amount required to produce a toxin that induces food poisoning. In this way, the degree of contamination of food poisoning bacteria was lower in the production environment of the Korea strawberry and tomato, but problems can be caused by post-harvest management method. These results will be used as fundamental data to create a manual for sanitary agricultural environment management, and post-harvest management should be performed to reduce the contamination of hazardous microorganisms.

• Journal of the Korean Society of Food Culture
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• v.31 no.1
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• pp.88-95
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• 2016

This study evaluated the quality characteristics of dried noodles prepared with strawberry powder in order to determine the most preferred noodle recipe for children's school meals. The proximate composition of strawberry powder used was as follows: moisture, 3.39%; crude protein, 1.53%; crude lipid, 0.97%; crude ash, 0.82%; and carbohydrates, 93.29%. When viscosity of the composite strawberry powder-wheat flours was measured by amylograph. Gelatinization point, maximum viscosity, viscosity at $95^{\circ}C$ and viscosity at $95^{\circ}C$ after 15 min decreased as the level of strawberry powder increased. As the level of strawberry powder increased, both L and b color values decreased, whereas a value increased. Weight, water absorption and volume of cooked noodles decreased, whereas turbidity of soup increased. For textural properties, addition of strawberry powder to cooked noodles reduced hardness, chewiness and brittleness. Overall preference according to the results of the sensory evaluation, noodles added with 6% strawberry powder were the most preferred. According to the results, the addition of strawberry powder can positively affect the overall sensory evaluation of dried noodles, and 6% is the optimal level for addition.

• Korean Journal of Organic Agriculture
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• v.22 no.4
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• pp.657-665
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• 2014

This study was carried out to study the effect of eggplant (EG203) grafting and strawberry removal time on succeeding tomato cropping in high temperature season. In non tillage culture, bacterial wilt incidence was 30% and 0% in nongrafting and eggplant (EG203) grafting while 25% in non-grafting and 0% in eggplant (EG203) grafting in tillage culture. Commercial yield was similar in tillage and non-tillage culture using EG-203 grafting as 2,693 kg/10a and 2,657 kg/10a respectively with no difference in soluble solid content and hardness. Strawberry removal time after tomato planting enhanced plant height and internode length in 20days and 30days later removal while no difference in other growth characters. Commercial yield was higher as 1,885 kg/10a in strawberry removal before tomato planting than 1,678 kg/10a in 30days later removal. From this research, strawberry removal time should be determined by considering strawberry price and growth and expecting profit by succeeding tomato cropping.

• Korean Journal of Plant Tissue Culture
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• v.28 no.3
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• pp.173-173
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• 2001

• Korean Journal Plant Pathology
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• v.11 no.4
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• pp.298-303
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• 1995

The biological control effect of Trichoderma harzianum on the Fusarium wilt of strawberry and several factors affecting on its efficacy were examined through pot experiments. T. harzianum grown on wheat barn, rice straw, rice hull, sawdust or barley straw was respectively incorporated into the pathogen-infected soil, and significantly suppressed the strawberry wilt caused by Fusarium oxysporum f. sp. fragariae. The wheat bran or rice straw culture of T. harzianum suppressed the disease incidence more effectively than other substrates for culture, decreasing it to 68% of the untreated control. The conidial suspension of T. harzianum alone or the suspension mixed with crab shell also effectively reduced the disease incidence. The control effectiveness of T. harzianum was high in acid soil (pH 3.5~5.5). In sandy loam soil, the disease incidences and population densities of the pathogen were decreased by the treatment of T. harzianum, while there was no significant effect of T. harzianum on the pathogen in loam soil.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.445-451
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• 1998

A severe Phytophthora rot of strawberry caused by a species of Phytophthora has been widely occurred at major cultivation areas of Kimhae on August in 1997. Incidence of the disease was obtained in the range of 69.2~83.6% in surveyed 4 fields and showed an average of 75.2%. A species of Phytophthora was mostly isolated from the crown of infected strawberry plants and all the isolates were identified as P. nicotianae var. nicotianae (=P. parasitica). The fungus showed strong pathogenicity on strawberry by inoculation test. As a result of the leaf inoculation using mycelial disks of the fungus, both leaves and petioles were darkly browned, and were finally blighted. As a result of the root inoculation of zoospore suspension, both roots and crowns were rotten with dark brown. Although the fungus produced sporangia either on V-8 juice agar medium or liquid medium, the sporangia observed on the liquid medium appeared to be broadly turbinate and noncaducous. Moreover the fungus cultured on the liquid medium often produced sporangia having two papilla. The number of zoospores in sporangia was found to be ranged from 3 or 4 to as many as 20 or 25. In addition, the released zoospore from the sporangium became the cystospore during the prolonged culture of the fungus. The sporangia were measured as av. 49$\times$35 ${\mu}{\textrm}{m}$ with l/b ratio of 1.43. All isolates from crowns were heterothallic and A1 mating type since oospores were abundantly formed on clarified V-8 juice agar by dual culture with P. capsici A2 mating type. Aplerotic oospores were sized 24-26 ${\mu}{\textrm}{m}$. Antheridia were always amphigynous and recoreded an average of 12$\times$10 ${\mu}{\textrm}{m}$. Hyphal swlling were easily observed, and terminal or intercalary chlamydospores were abundantly formed on V-8 juice agar as well as in C/Z solution and sized av. 28.2 ${\mu}{\textrm}{m}$. This is the first report of Phytophthora rot of strawberry in Korea.