• Korean Journal of Environmental Agriculture
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• v.17 no.4
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• pp.306-311
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• 1998

Effects of soluble silicon and surfactants on the development of powdery mildew of cucumber were tested for environmentally safe powdery mildew control. Tested soluble silicon was potassium silicate$(K_2SiO_3)$ and tested commercial surfactants were Jeonchakje, Silhouette, Kaba, and Tween 20. Tested concentrations were 2, 4, 8, 16mM for the soluble silicon, 0.5 and 1.0% for Tween 20, 0.05 and 0.1% for both Jeonchakje and Kaba, and 0.03 and 0.07% for Silhouette. Water dilutions of tested materials were sprayed on cucumber (Cucumis sativus) leaves once a week for 4 weeks. From 3 days after the second spray, the diseased area and the numbers of fungal colony were measured from the treated leaves for 6 times at 3-4 days interval. Powdery mildew was less severe on treated cucumber compared to distilled water-treated cucumber (check). In all treatments, diseased area index was proportional to the number of the fungal colony. At the end of investigation, there was severe powdery mildew on check cucumbers. Average 30% of a leaf was colonized by powdery mildew fungus and the average number of the fungal colony per leaf reached to more than 70. On the other hand, none of the treated cucumber suffered severe powdery mildew. The treatments including 8 and 16mM of soluble silicon, doubled concentration of Kaba, and 0.5 and 1.0% of Tween 20 showed more than 80% of control effect compared to water-treated cucumber. In addition, no phytotoxicity was found. Potassium silicate and Tween 20 showed the possibility to replace chemical pesticides for the control of powdery mildew.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.1
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• pp.26-29
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• 2016

This study investigated the effects of dietary inclusion of sea mud on growth and body composition of juvenile sea cucumber Apostichopus japonicus. In experiment 1, three experimental diets containing sea mud at the level of 0, 30 and 60% were prepared. After feeding trial for 7 weeks, survival was not significantly different among groups. Final mean weight of sea cucumber fed the experimental diet without sea mud supplementation was significantly higher than that of sea cucumber fed the diet containing 30 and 60% sea mud. In experiment 2, three experimental diets containing sea mud at the levels of 0, 15 and 30% were prepared. After feeding trial for 19 weeks, survival was not significantly different among groups. Final mean weight of sea cucumber fed the diet without sea mud supplementation was not significantly different from that of 15%, but was significantly higher than that of sea cucumber fed the diet containing 30% sea mud. It was concluded that dietary inclusion of sea mud may inhibit growth of sea cucumber.

• Research in Plant Disease
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• v.14 no.2
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• pp.138-141
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• 2008

Cucumber is high valued cash crop, for it is grown during the winter season in plastic house. Recently, virus disease spread widely in cucumber growing area and cause severe income loss. Therefore, occurrence of virus disease on cucumber were surveyed from 2004 to 2006 in Sangju and Gunwi area, Gyeongbuk province. The rate of plastic house which has infected plants was $55.0{\sim}88.6%$. Infection rate was the highest at Sangju in 2006 than others and ranged from 15 to 90.0% per plastic house. The 217 samples showing virus symptom were analyzed by RT-PCR using appropriate detection primer. Zucchini yellow mosaic virus(ZYMV) has the highest infection rate(detected over 85%) and followed by Cucumber green mottle mosaic virus(CGMMV). But Watermelon mosaic virus-2(WMV-2) was not detected in our survey. Therefore, we conclude that ZYMV is major pathogene of virus disease on cucumber. ZYMV induced chlorosis and severe mosaic on the leaves and distortion on the surface of fruits.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.1
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• pp.131-138
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• 2015

In this study, cucumber Jangachi using Sake cake was prepared and its quality characteristics verified. After preparing various cucumber Jangachi with different salt concentrations, physicochemical characteristics, hardness and sensory evaluation were investigated. Five samples (0%, 3%, 6%, 9% and 12% brine) were used and designated as treatment plots (CJ0, CJ3, CJ6, CJ9 and CJ12, respectively). Higher concentration of brine was associated with reduced pH of cucumber Jangachi and higher total acidity. Salinity decreased significantly as storage period increased. On day 0, it shows similarity to the concentration of brine, whereas it was reduced after day 28. The soluble solid content increased significantly as the storage period increased and decreased slightly after 21 days. Regarding concentration of brine, a higher concentration shows a tendency to increase but the gaps are insignificant. Reducing sugar content increased significantly as the storage period increased. The hardness increased in all treatment plots up to the 14th day, decreased until day 21, and increased thereafter. Following the sensory evaluation, saltiness was not detected in the plots, and CJ6 showed the highest texture score ($4.46{\pm}1.41$). For overall acceptability, CJ6 showed the highest score ($4.33{\pm}1.13$). According to the above results, salinity content of cucumber Jangachi using Sake cake decrease to 0.69~1.52% in 0%, 3%, 6%, 9%, and 12% brine by the 28th day. Despite decreasing salinity, texture and overall acceptability scores were higher than the above results. Thus, we conclude that it is possible to produce low salt cucumber Jangachi of high quality using Sake cake instead of high salt one.

• The Plant Pathology Journal
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• v.23 no.3
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• pp.223-225
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• 2007

Many plant growth-promoting rhizobacteria (PGPRs) have been known for beneficial effects on plants including biological control of soilborne pathogens, induced systemic resistance to plant pathogens, phytohormone production, and improvement of nutrient and water uptake of plants. We developed a simple and rapid method for screening potential PGPR, especially phytohormone producing rhizobacteria, or for analyzing their functions in plant growth using cucumber seedling cuttings. Surface-sterilized cucumber seeds were grown in a plastic pot containing steamed vermiculite. After 7 days of cultivation, the upper part 2 cm in length of cucumber seedling, was cut and used as cucumber cuttings. The base of cutting stem was then dipped in a microcentrifuge tube containing 1.5ml of a bacterial suspension and incubated at $25^{\circ}C$ with a fluorescent light for 10 days. Number and length of developed adventitious roots from cucumber cuttings were examined. The seedling cuttings showed various responses to the isolates tested. Some isolates resulted in withering at the day of examination or in reduced number of roots developed. Several isolates stimulated initial development of adventitious roots showing more adventitious root hair number than that of untreated cuttings, while some isolate had more adventitious root hair number and longer adventitious roots than that of untreated control. Similar results were obtained from the trial with rose cuttings. Our results suggest that this bioassay method may provide a useful way for differentiating PGPR's functions involved in the development of root system.

• Journal of Plant Biotechnology
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• v.43 no.3
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• pp.341-346
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• 2016

The objectives of this study were to 1) evaluate the efficiency of the protocol of Agrobacterium-mediated transformation of cucumber to introduce phytoene synthase-2a carotene desaturase (PAC genes); 2) demonstrate the integration of PAC genes into the genome of putative transgenic cucumber based on growth on selection medium, PCR and Southern analysis; 3) evaluate the expression of PAC genes in transgenic cucumber based on the analysis of RT-PCR and Northern blot hybridization. Out of 5,945 cotyledonary-node explants inoculated with Agrobacterium, 65 (1.1%) explants produced 238 shoots. Integration of PAC genes into the genome of the cucumber was demonstrated based on the analysis of gDNA-PCR, 21 out of the 238 plants regenerated; while 6 plants proved positive for Southern blot hybridization. Transgene expression was demonstrated based on analysis of RT-PCR, 6 plants proved positive out of the 6 plants analyzed; while 4 plants out of 6 proved positive during Northern blot hybridization. This study successfully demonstrated the production of transgenic cucumber, integration, and expression of the PAC gene in cucumber.

• The Korean Journal of Food And Nutrition
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• v.14 no.5
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• pp.385-390
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• 2001

The enzyme activity and organoleptic properties of Korean pickled cucumber were studies for their changes during fermentation. The Korean pickled cucumber were prepared by blanching and high temperature soaking in salt solution and trehalose treament. The results showed that the effect of combined heat and trehalose treatment significantly reduced the fermentation rate and softening rate of texture while a rather rapid fermentation was for those preserved with salt. The effect of terhalose treatment enhanced fermentation and it was significantly reduced softening rate of texture by 2% treatment. The sensory evaluation of Korean pickled cucumber was found that combined heat treatment with blanching and hot solution had a positive effect for reduction of softening of cucumber tissue, however, odor and taste were not significantly affected. This study suggested that combined heat and trehalose treament might have potential for affording protection against softness of cucumber tissue during the fermentation time.

• Culinary science and hospitality research
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• v.23 no.4
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• pp.185-192
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• 2017

This study examined the optimum conditions and obtained the basic data for processing semi-dried sea cucumber flakes. During the boiling process, the weight and length of the sea cucumber decreased to 45.61% and 55.87%, respectively. Thereafter, there was a gradual decrease in the weight and length of the sea cucumber, which were finally maintained at 30.00% and 50.93%, respectively. The moisture content during drying was 38.37% after 3 hours at $60^{\circ}C$, and 36.56% after 5 hours at $30^{\circ}C$. However, the decrease in moisture content was slowly at 60 hours and $4^{\circ}C$, reaching a final value of 68.9%. The length of boiled sea cucumber during drying decreased to 66.35% after 11 hours at $60^{\circ}C$, and 68.90% after 24 hours at $30^{\circ}C$. The chromaticity and hardness tended to increase during the drying process. Moisture content and water activity of sea cucumber flakes decreased from 81.48% (0.963) to 33.50% (0.763), respectively, after 3 hours at $60^{\circ}C$. Following this, the moisture content and water activity continuously decreased to 30.75% (0.608) at 4 hours and 19.47% (0.437) at 5 hours, respectively. The overall acceptance score was 4.11 and 3.89 for 4 hours dry sample and 5 hours dry sample, respectively. However, the score was not statistically significant.

• Journal of Applied Biological Chemistry
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• v.55 no.2
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• pp.135-140
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• 2012

To diversify usage of aquacultural red sea cucumber, new Kimchi containing red sea cucumber was developed and its quality and consumer preference were studied. The pH and total acidity, index of Kimchi ripening, decreased till 7 days of storage, then pH change became blunt and finally reached optimum pH 4-4.5. The amount of reducing sugar gradually decreased during storage period. The number of lactic acid bacteria increased in early fermentation period in both Kimchi containing boiled and fresh red sea cucumber, however, more lactic acid bacteria found in fresh red sea cucumber containing Kimchi. Preference of Kimchi containing boiled or fresh red sea cucumber compared to control Kimchi containing fermented salted fish was evaluated. The results revealed there were no differences in color, flavor, texture, taste, after taste and overall preference.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.263-266
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• 2011

Crop protection strategies in organic horticulture aim to prevent insect pest and plant disease problems through utilization of non-chemical based control means. In order to develop a model for management of plant diseases and insects in organic cucumber cultivation, we compared efficacies between chemical pesticide spraying system and biological control means in semi-forcing and retarding cucumber cultivation during 2005 and 2006. Conventional chemical spray program using various chemical pesticides was applied 5 - 10 days intervals, while two different non-chemical pesticide application programs using two formulated biopesticides Topseed$^{TM}$ and Q-fect$^{TM}$, Suncho$^{TM}$, and Sangsungje$^{TM}$ (biocontrol agents 1) and using egg-yolk and cooking oil(EYCO), Bordeaux mixture, Suncho$^{TM}$, and Sangsungje$^{TM}$ (biocontrol agents 2) were applied 5 - 7 days intervals during entire cucumber cultivation period. Efficacy of both biocontrol agents programs was effective to comparable to conventional chemical pesitice spray program to control plant diseases such as powdery mildew and downy mildew as well as insect pests such as aphids and thrips which are known as major threats in cucumber organic cultivation. In this study, we established and evaluated an effective and economic crop protection strategy using various biological resources can be used to control plant diseases and pests simultaneously in organic cucumber cultivation field.