• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.28 no.3
• /
• pp.231-236
• /
• 2022

The research was aimed to improve pre-harvest methods to maintain marketability in postharvest leaf lettuce. In this study, the effect of hydroponics on the growth and post-harvest storage characteristics of 'Chongchima' lettuce grown in peat mass medium hydroponic system using a non-powered culture device or deep water culture (DWC) was evaluated. There was no difference in fresh weight, leaf number, SPAD, moisture content, and C/N ratio between peat moss growing medium hydroponic and DWC methods except plant height. It was found that lettuce cultivation by a nonpowered hydroponics method is easier than the existing DWC. The quality parameters, such as fresh weight loss, SPAD value, and general appearance of lettuce were investigated after harvest. There was no significant difference in fresh weight loss and general appearance during storage of lettuce by the hydroponics methods. However, with the increased storage time of SPAD, which is related to chlorophyll content, was slightly higher in peat moss medium hydroponic was than DWC. When crops such as lettuce are grown under favorable conditions without any agronomic abnormalities, it is suggested that post-harvest storage is not significantly affected by peat moss growing medium hydroponic and DWC.

• Research in Plant Disease
• /
• v.10 no.1
• /
• pp.13-16
• /
• 2004

A basal stem rot disease of potato (Solanum tubersum) grown on hydroponic system in greenhouse was found in Jeju-city, Jeju Province of Korea in January 2001. The symptoms occurred on basel stem and root, and than plants eventually were died. The casual fungus isolate from basal stem rot symptom and identified to be Pythium myriotylum on the basis of mycological characteristics; Main hyphae wide were 8.4 ${\mu}{\textrm}{m}$ in size. Oogonia were spherical, smooth, mostly terminal in shape and 26.4∼31.2 ${\mu}{\textrm}{m}$ in size. Antheridia were 9.6∼14,4${\times}$4.8-9.6 ${\mu}{\textrm}{m}$ in size. Oospores were spherical, smooth, aplerotic in shape and 21.6∼26.4 ${\mu}{\textrm}{m}$ in size. This is the first report on the basal stem rot of potato caused by P. myriotylum in Korea.

• Journal of Bio-Environment Control
• /
• v.32 no.2
• /
• pp.132-138
• /
• 2023

The Gymnocalycium mihanovichii has been an important export item of Korean flower industry for a long time. Although there is a high demand for grafted cactus from overseas, its production for export is limited. In this study, the growth and marketable yield characteristics of Gymnocalycium mihanovichii 'I-Hong' were compared between soil culture and ebb-and-flow hydroponic system with single- or double-tier bench. As a result, hydroponic methods with single-tier bench resulted in higher fresh weight and glove diameter compared to other cultivation methods. In the ebb-and-flow hydroponic system, hydroponic system with double-tier bench of grafted cactus traits has a lower growth rate than other cultivations. However, the hydroponic system with double-tier bench of grafted cactus significantly increased the yield. In conclusion, the yield from hydroponic system with double-tier bench was better than soil cultivation method. Although there were some differences in color depending on the cultivation method, it was considered that there was no difference in appearance of Gymnocalycium mihanovichii 'I-Hong'. Our results suggest the cultivation methods to overcome production constraints, expand their exports, and improve the value-added characteristics of grafted cactus.

• Journal of Bio-Environment Control
• /
• v.2 no.1
• /
• pp.53-57
• /
• 1993

This study was carried out to investigate the appropriate hydroponic system when cherry tomatoes were grown in summer. The base diameter of the trunk, leaf length, leaf width, and the length of cluster were good in deep flow culture(DFC), and not different between NFT and rockwool culture. The first time of flowering and the fruit coloring per cluster were not different among cultural systems, but the marketable yields were good in DFC. In DFC, ％ dry weight, firmness, the content of organic acid and sugar were low, and the ratio of sugar/organic acid and vitamin C were high. So DFC is recommended for the summer cultivation of cherry tomatoes.

• Journal of Bio-Environment Control
• /
• v.6 no.4
• /
• pp.284-291
• /
• 1997

This study was conducted to evaluate the optimum hydroponic system and nutrient solution for shortening the early growth period and quality improvement of dendrobium ( Dendrobium Phalaenopsis) seedlings. Dendrobium seedlings with 3 to 4 leaves were transplanted in the deep flow technique(DFT) system, aeroponic system, and ebb and flow system with different concentration of balanced nutrient solutions recommended by the Japanese Horticultural Experiment Station. Growth characteristics of shoot and root were recorded and evaulated among treatments. For autumn cultivation, plant height was the longest at the DFT system with quarter concentration of nutrient solution, where aeroponic system with half concentration of nutrient solution. Aeroponic system stimulated the root growth but fresh weight was observed in the plots of DFT system. For spring cultivation, pH values increased up 7.5 at the DFT and aeroponic system, where EC values did not fluctuate regardless of cultural system. Ebb and flow system showed the best result in the growth of plant followed by BFT system and aeroponic system. Higher concentration of nutrient solution within this range of treatment was recommended for the growth promotion of leaf length and width in DFT system. In conclusion, growth responses differed depending on the cultural system, concentrations of nutrient solutions and duration of cltivation.

• Journal of Bio-Environment Control
• /
• v.8 no.1
• /
• pp.19-29
• /
• 1999

This experiment was conducted to compare with the growth and fruit quality of Citrullus lanatus cv. Mudeungsan and Citrullus vulgaris cv. Dalgona grown in fertigation and soilless culture. Seeds were sown on April 16 and transplanted on April 24, 1998. Cultural systems used in fertigation and soilless culture beds using mixed substrate, coir dust (50%) and perlite (50%). In the plot of fertigation system, the number of leaves of cv. Dalgona were increased more than that of cv Mudeungsan, but leaf area shown inversed trend. Plant growth shown greater in soilless culture than those of fertigation culture. In regardless of cultural systems, soluble solid content in fruit was higher in the cv. Dalgona than that of cv. Mudeungsan, but fruit fresh weight was greater in cv. Mudeungsan compare to the cv Dalgona. Nitrate content in petiole sap of watermelon in regardless of cultivars and cultural systems was 11.4∼13.4mg/gFW on 15 days after transplanting, and then increased to 17.1∼20.6mg/gFW on the fruit growth stage. Phosphorous content was 3.7∼5.7mg/gFW in the early growth stage while decreased to 0.6∼1.1mg/gFW from maturing stage to harvesting stage. Potassium content was increased to 5.8∼6.6mg/gFW in the early growth stage while decreased to 4.0∼4.8mg/gFW from pollination stage to harvesting stage. Calcium content in spa petiole of watermelon was higher in soilless culture as 3.4∼4.1mg/gFW than 2.5∼3.5mg/gFW of fertigation culture, but calcium content in fertigation culture during maturing stage was higher than that of soilless culture. The tendency of magnesium uptake was higher in fertigation culture than that of soilless culture, and was similarly absorbed in the range of 0.9∼1.3mg/gFW in regardless of cultural method after pollination. It was demonstrated that cv. Mudeungsan can be adapted to soilless culture and improved the fruit quality. Consequently, hydroponic possibility for year round culture in the greenhouse was recognized.