• Journal of Korean Society of Forest Science
• /
• v.90 no.1
• /
• pp.74-82
• /
• 2001

The effects of Al and Mn concentration on dry weight growth, nutrient status and gas exchange rates of 2-Year-old Japanese red pine(Pinus densiflora) seedlings grown in a nutrient culture solution were investigated. Al was added as aluminum chloride at 0, 10, 30 or 60ppm, and Mn was added as manganese chloride at 0, 30 or 60ppm to the nutrient culture solution. The pH of the solution was maintained at 4.0 by adding HCl or NaOH solution. The seedlings were transplanted into the nutrient culture solution, then they were grown in a greenhouse for 90 days. The interactive effects of Al and Mn on the dry weight growth of the seedlings were not significant. There were a main effect of Al or Mn on the dry weight growth and element concentrations of the seedlings. The treatment with Al of ${\geq}10ppm$ or that with Mn of 60ppm induced a significant reduction in the dry weight growth, which indicates that the effect of Al is stronger than that of Mn. The chlorophyll content of needles was not affected by Al treatment, but was significantly reduced by treatment with Mn of 60ppm. Furthermore, the treatment with Al of 60ppm or that with Mn of ${\geq}30ppm$ caused a significant reduction in the dark respiration rate of the roots. The net photosynthetic rate of the seedlings reduced with increasing the concentration of Al or Mn in the nutrient culture solution, which suggests that Al or Mn induced reductions in the relative growth rate(RGR) and net assimilation rate(NAR) of the seedlings were mainly due to the decrease of net photosynthesis.

• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.6
• /
• pp.1300-1305
• /
• 2011

The study was conducted to investigate the characteristics of flower quality and yield of gerbera 'Sunny Lemon' by mutrient solution strength and media of nutrient solution. The plant growth of 'Sunny Lemon' showed the highest values in the media of rockwool and perlite 1: peatmoss 2. Especially the yield of cut flowers for a year was more than 60 flowers and the flower longevity was over 10 days irrespective of nutrient solution concentration in the two media. There were no significant differences of plant characteristics in the nutrient concentration of 1/2 and 1 times, and the mineral nutrient contents showed similar values. Therefore, we recommended the media of perlite1: peatmoss2 with the concentration of 1/2 times for economical use. The rockwool media was not appropriate because of the weak buffer capacity like EC and pH.

• Journal of Plant Biotechnology
• /
• v.48 no.3
• /
• pp.193-200
• /
• 2021

Barley (Hordeum vulgare cv. Hangmaeg) sprouts are important microgreens that contain high levels of polyphenols and flavonoids, as well as minerals, vitamin and chlorophyll. Barley sprouts were grown for 9 days and growth was checked every 3 days. In this study, the cultivation efficiency according to the nutrient solution treatment was evaluated by analyzing the length of barley sprouts, fresh weight, chlorophyll, and the yield by growth period. In addition, we tried to increase the industrial applicability of germinated barley through analysis of inorganic component, total polyphenol and total flavonoid content of the extract, and functional substance analysis using HPLC. As a result, the growth rate of the nutrient solution treatment group was faster than that of the control group. When harvested on the 9th day of sowing, the nutrient solution treatment group showed a significant increase in yield compared to the control group. And the barley sprout extract of the nutrient solution treatment group had higher total flavonoid content and luteolin content. Also, the efficiency of water was higher than that of ethanol when extracting phenolics from barley sprouts. Therefore, this study suggests that nutrient input is effective for increasing polyphenol content and increasing production in barley sprout hydroponics.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.41 no.2
• /
• pp.37-43
• /
• 1999

This study was conducted to develop the simple and convenient irrigation control model which can maintain the appropriate rates of irrigation and drainage of nutrient solution according to the enviornmental conditions and growth stages in soilless culture of cucumber. In order to obtain fundamental data for development of the model, investigation of the actual state of soilless culture practices was carried out. Most irrigatioin systems of soillness culture were controlled by the time colock. Evapotranspiration of cucumber in soilness culture was investigated and correlations with environmental conditions were analyzed , and its estimating model was developed. In order to develop the irrigation system which can control the amount of nutrient solution applied according to seasons, weather conditions, and growth stages, a irrigation clock control was developed. Applicability of the model was tested by simulation. Drainage rates of nutrient solution controlled by conventional time clock, integrated solar radiation, and the developed model were 61% , 20%, and 32% , respectively in cucumber perlite culture.

• Journal of Biosystems Engineering
• /
• v.28 no.4
• /
• pp.335-342
• /
• 2003

A simple disposable thick-film potentiometric strip has been developed and evaluated for hydroponics application. The strip consisted of low ion-selective electrodes (ISE) fabricated by screen-printing technology. The electrochemical responses of ion sensors for nitrate, ammonium, potassium, and magnesium were measured with specially designed 16-channel low voltage signal transducers. The analytical characteristics of the sensors were comparable with those of conventional ISE sensors. The thick-film sensors exhibit linear relationships over five concentration decades. The concentration of N $O_3$ - ion in standard solution can be determined by direct potentiometric measurements without any conditioning before measurements. However, measurement of $K^{+}$, N $H_4$$^{+}$, and $Mg^{2+}$ ionic concentrations in nutrient solutions seems not feasible.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.48 no.3
• /
• pp.200-204
• /
• 2003

This study was conducted to develop a technology for raising seedlings hydroponically using the bed in which the seedlings grew in nutrient solution without soil. In order to establish the optimum EC value of nutrient solution, six initial EC values (1, 2, 3, 4, 5 dS/m and control) of Yoshida's hydroponic solution were examined. Seedling height and dry weight increased with increasing below EC up to 3.0 dS/m, but showed no significant increase at higher than EC 3.0 dS/m. Nutrient solution with initial EC of 3.0 dS/m was good to be dropped down nearly to 1 dS/m after 15-day seedling culture. But those with initial EC of 4.0 and 5.0 dS/m were judged not appropriate because of high EC value in waste nutrient solution. Utilization efficiency of minerals of nutrient solution and rice endosperm was higher on the whole at initial EC of 2.0-3.0 dS/m. Considering seedling growth and utilization efficiency of supplied nutrient solution, initial EC is judged to be suitable at 3.0 dS/m.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.48 no.3
• /
• pp.205-208
• /
• 2003

This study was conducted to develop a technology for raising rice hydroponically seedlings using the bed in which the seedlings grew in nutrient solution without soil. In Hydroponic rice seedlings, two nutrient solutions (Yashida and Wonsi) were evaluated with four supplying methods $[$3 times (2 days, 8 days and 12 days after seeding), 2 times (5 days and 10 days after seeding), and 1 time (5 days and 10 days after seeding)$]$1, Seedling growth was not different between the two solutions. However, tensile strength of root-mat was higher in Yoshida solution than in Wonsi solution. The more frequent supply of solution resulted in the better seedling growth but in the weaker root mat. Utilization efficiency of the solution minerals was not different in N content regardless of supplying frequencies, but higher in r, K, Ca and Mg when supplied only once on the 5 days after seeding.

• Horticultural Science & Technology
• /
• v.30 no.2
• /
• pp.137-143
• /
• 2012

Chinese cabbage plant was grown hydroponically for 4 weeks in order to examine the temporal relationship of calcium concentration of the nutrient solution with calcium content in the leaf tissue and susceptibility of the tissue to soft rot disease by $Pectobacterium$ $carotovorum$ ssp. $carotovorum$ (Pcc). Calcium concentration from 0.5 to 32.0 mM was maintained for 1 week using Hoagland & Arnon solution. The calcium content of the leaf was proportionally increased to the concentration of the nutrient in the solution (r = 0.912). In contrast, the severity of soft rot symptom in the young leaves was inversely related with the amount of calcium supplied to the nutrient solution (r = 0.899). Water-soluble chitosan, prepared by hollow fiber filtration (> 100 kDa) was applied into the nutrient solution from 0.0 to 5,000 ppm. The chitosan of 10 ppm was the most effective to promote calcium uptake of the leaf, showing 155% of the control. The same chitosan solution prohibited most soft rot development of the leaf by Pcc, exhibiting only 53% of the control. Among different molecular weight fractions, chitosan fraction obtained from 30-100 kDa molecular weight cut-off promoted calcium uptake the most up to 163% of the control, and reduced the development of soft rot disease recording merely 36% of the control of the leaf tissue. The results obtained in the present study suggest that large scale production of water-soluble chitosan with an optimum molecular weight and its commercial application to Chinese cabbage production will be important to improve yield and quality of the crop.

• Journal of Plant Biotechnology
• /
• v.6 no.2
• /
• pp.107-111
• /
• 2004

To establish an efficient acclimation system for regenerated plantlets of soybean, we used various media with hydroponic nutrient solutions before regenerants were transplanted into soil. The hydroponic nutrient solution was essential for the survival of the plantlets. The vermiculite with nutrient solution at pH 5.5 was found to be the best medium with 97-100% survival rate and better growth of regenerants plantlets. Regeneraed grew best in the following order of solutions: Yoshida solution, modified Yoshida solution, SoyI, Soy II, and MS medium. However, Soy I solution (EC 2.9 mS/cm), developed by the Honam Agricultural Research Institute proved to be the most effective for acclimation in terms of the time required for vigorous growth and economical use of chemicals.

• KSBB Journal
• /
• v.19 no.3
• /
• pp.241-244
• /
• 2004

An automated flow injection analysis apparatus manufactured economically was used in the automatic measurement of E. col growth in shake-flask culture of nutrient broth. The detailed measurement of whole growth was possible at intervals of 10 minutes by the automatic measurement system which adopted the sterilized nutrient broth as a carrier solution. Using distilled water as a carrier solution showed less accurate results than nutrient broth.