• Journal of agriculture & life science
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• v.45 no.6
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• pp.265-278
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• 2011

Effects of the open level of the side window were studied to control the temperature and relative humidity in the fog cooling greenhouse. The greenhouse was cooled by air atomizing spray nozzles of the air and water two-fluid process. The control process includes the measuring of environmental variables, setting and coding of the water balance equations and heat balance in greenhouse, calculating of the roof window open and spray water, and operating of the motor and pump. The target temperature and relative humidity were set at $28^{\circ}C$, 75%, respectively. The three modes of the side window open level were 0%, 50% and 100%. The average dry bulb temperatures of the inside air were 28.2, 27.2 and $26.3^{\circ}C$, respectively and their standard deviation was ranged from $0.4^{\circ}C$to $0.8^{\circ}C$. Also the relative humidity of the 0% mode was the best controlled one with the average of 76.3% and the standard deviation of 2.1%.

• Journal of Bio-Environment Control
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• v.18 no.2
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• pp.171-176
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• 2009

Hydroponic culture has been developed to control soilborn diseases, to increase yield and to enhance the quality of vegetable, The pathogen could be detected from infected plant materials, hydroponic tanks, culture solution and solid media of the severely infected greenhouse, The density of pathogen population was coincided with the severity of disease incidence, For example, 1,900cfu m$L^{-1}$ pf pathogens were counted from tomato plants sampled in a 20% diseased greenhouse. The pathogens may be introduced in the greenhouse through the contaminated soil surrounding the house and/or through the infected young seedlings grown on the nursery soil. Also, not detected to Ralstonia solanacearum from tomato seeds (House Momotaro, Bbaebbae, Ggoggo, and Minicarol cultivar) selling at a market.

• Journal of Environmental Science International
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• v.31 no.11
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• pp.951-958
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• 2022

The aim of this study was to determine the optimum level of carbon dioxide to maximize the quality and yields of strawberries cultivated in a greenhouse. Specifically, two strawberry cultivars, namely, 'Seolhyang' and 'Maehyang', were subjected to varying concentrations of carbon dioxide and patterns linked to their productivity were noted. Both cultivars showed improvements across various physical variables (i.e., leaf area, crown diameter, plant height, fresh weight, and dry weight) when carbon dioxide concentrations were at 1,500 ppm. The optimum carbon dioxide concentration for increased fruit yields and quality was 1,000 ppm. When carbon dioxide was at 1,000 ppm the yields of 'Seolhyang' and 'Maehyang' increased by 1.99 and 1.78 times, respectively, compared to control plants. The influence of carbon dioxide on fruit color was negligible. However, the carbon dioxide increased the sugar content and sugar-acid ratio of the experimental fruits compared to control plants. Specifically, the sugar-acid ratio, which is directly related to taste, was at its highest when the concentration of carbon dioxide was at 1,000 ppm (i.e., for both 'Seolhyang' and 'Maehyang'). Overall, the application of carbon dioxide culminated in improved yields and fruit quality for both cultivars of interest.

• Plant Resources
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• v.3 no.2
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• pp.131-134
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• 2000

Embryogenic callus cultures of Korean native Seosanjong of ginger(Zingiber of officinale Rosc.) were induced through stem explants taken from in vitro shoot-tip cultures. Among the four concentrations of 2,4-D tested in Murashige and Skoog medium, 0.5 and 1 mg/L of 2,4-D was most effective in inducing embryogenic callus. Leaf explants did not express any new morphogenetic response in all 2,4-D concentrations tested. Plantlets transferred to hormone-free MS medium were developed and successfully acclimatized under greenhouse.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2007.05a
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• pp.115-118
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• 2007

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1996.10a
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• pp.42-53
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• 1996

Storage methods to suppress growth of transplants and maintain their quality are required for successful commercial transplant production, since peak demand for transplants of flower or vegetable species falls during limited periods in spring and fall, due to the seasonal nature of the horticulture industry. Plug seedlings, probably due to their high planting density and limited rhizosphere, easily elongated or overgrown during the holding period before the market or greenhouse space is available. (omitted)

• Horticultural Science & Technology
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• v.19 no.4
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• pp.488-494
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• 2001

Seedlings of strawberry, 'Reiko' were planted in plastic pots of 24 cm in diameter in the middle of September in 1995, 1996, and 1997. Ten plants were transferred to greenhouse with artificial illumination at 5-day interval from late September to late January. The deepest dormancy of 'Reiko' in Daegu area was found to be on November 5, October 25, and October 31 in 1995, 1996, and 1997, respectively. The time for moving plants to make the plants grow in semi-dormant state in the greenhouse occurred between Nov. 10 and Nov. 20 in both 1995 and 1996, and between Nov. 10 and Nov. 30 in 1997. The time passing approximately 100-200 cumulative hours of exposure to below $5^{\circ}C$ canopy temperature from the peak dormancy, which is required for breaking dormancy of 'Reiko', was between November 16 and 25 in 1996, and November 24 and December 5 in 1997. 'Reiko' yielded high every year when seedlings were moved into greenhouse during the period of October to November. The plants gave good response to forcing culture under lighting. The right time for moving plants into greenhouse in semi-forcing culture appeared to be the time passing 50-150 cumulative hours of exposure to below $5^{\circ}C$ canopy temperature from the peak dormancy.

• Horticultural Science & Technology
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• v.30 no.6
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• pp.680-685
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• 2012

The objective of the experiment was to investigate the effect of two growing areas in the greenhouse on the plant growth characteristics, physiological responses and yield attributes of the 'Cupra' sweet pepper. Two growing areas of the greenhouse were as follows, central part area (CA) and north part area (NA). Daily average temperature of the CA was $1.6^{\circ}C$ higher than those of NA. Plant height, number of internode, and SPAD value in the CA were significantly higher than NA both six weeks and twelve weeks after planting. Net photosynthesis of the sweet pepper leaves of the CA was significantly higher than those of NA. The total fruit yield of the sweet pepper was 20% higher in plants grown for CA than that of NA. These results suggest that air temperature in the greenhouse influenced plant growth characteristics, net photosynthesis and total yield of sweet pepper whether pepper plants were grown as CA or as NA.

• Korean Journal of Plant Resources
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• v.35 no.5
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• pp.675-685
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• 2022

A comparative analysis was performed on the soil chemical properties of greenhouse or open field where flower crops were grown from 2018 to 2020. The pH of greenhouse soils was kept slightly higher than the optimum range suggested by Rural Development Administration and that of open field soils was maintained within the optimum range for three years. The contents of organic matter (OM) were within the optimum range without significant change every year in both soils. Available phosphate (Av. P₂O₅) of greenhouse soils was the highest at 560 mg/kg in 2018, but it decreased every year and fell within the appropriate range in 2020. The concentration of Av. P₂O₅ in open field soils have fluctuated for three years, not showing a significant difference. Electrical conductivity (EC) of greenhouse soils was higher every year than the standard, 2.0 dS/m, but EC of open field soils remained below the standard. The contents of exchangeable cations were higher than the standard, showing significant differences among the years in greenhouse soils. In open field soils, other cations except exchangeable K⁺ were maintained higher than the optimal level and only Ca²⁺ showed a significant difference among the years. In Pearson correlation matrices, the value of exchangeable Ca²⁺ had a significantly positive correlation with exchangeable Mg²⁺ content at both greenhouse and open field soils. Based on principal component analysis, the soils of greenhouse were distributed within the range of high concentrations of Av. P₂O₅, EC and exchangeable cations, while the soils of open field were characterized by low contents of OM and exchangeable cations. Therefore, it is essential to lower the concentration of exchangeable cations in greenhouse soils. It is common for the soils of open field to have a low OM content, so that organic fertilizers should be more actively applied to the soils in open field.

• Horticultural Science & Technology
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• v.35 no.1
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• pp.79-87
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• 2017

We examined the effect of two greenhouse covering materials (glass or solid polycarbonate sheets) on the light environment and growth of tomato and cucumber plants. Spectral analysis showed that polycarbonate sheets entirely blocked radiation in both the UV - B (300 - 320 nm) and UV - A (320 - 400 nm) ranges, whereas glass transmitted UV - A and was only opaque to UV - B. The transmittance of photosynthetically active radiation (400 - 700 nm) and near infrared radiation (700 - 1100 nm) was higher in polycarbonate than glass. Air and soil temperatures were not significantly different between greenhouses covered with either material. The growth of cucumber plants was slightly affected by covering materials, whereas no significant changes in growth parameters were observed for tomato plants. The color parameters of tomato fruits were affected by the cover material, whereas cucumber fruits showed similar coloration in both glass and polycarbonate greenhouses.