• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.305-310
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• 2010

This study was carried out to investigate the effect of air humidity and water content of medium on the growth and physiological disorder of paprika in summer hydroponics. Treatments were composed of air humidity of control (over 90%) and dehumidification (low 90%) and water content of 80% and 50%. Time domain reflectometry (TDR) sensors and dehumidifier were used in a drip irrigation system and control system of air humidity, respectively. The early growth of paprika was not affected by air humidity but increased by high water content (80%) of medium. Mean fruit weight was reduced at high air humidity and low water content (50%) of medium, but the fruit number per plant and yield were increased at low air humidity. The incidence of brown fruit stem increased with increasing air humidity and water content of medium. Rate of blossom end rot increased in the low water content medium compared with the high water content medium. The nitrogen (N) was higher content in brown fruit stem than normal stem, but calcium (Ca) was lower.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.273-279
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• 2009

This study was conducted to identify optimal concentrations of N (nitrogen) and K (Potassium) fertilizers on growth, yield and quality of melon (Cucumis melo. L) when they were grown with a fertigation culture in a greenhouse. Three strength (S) levels of fertilizers, including 1 S, 1/2S, and 1/4S were supplied N and K nutrients as using a trickle irrigation system. When the strength level of fertilizers was increased from 1/4S to 1 S, the level of EC (electronic conductivity) in soil was increased. Soil-water tension was ranged between -15 and -20kPa until fruit setting stage, whereas it was ranged between -45 and -50kPa in the later growth stages. In results, N fertilizer had effects on fruit yield and quality. A higher fruit yield was observed when plants were supplied with 1 S and 1/2S level of N fertilizer. The highest yield of marketable fruit, about 5,086kg/10a, was also observed when plants were supplied with 1/2S N fertilizer. A higher net index and sugar content of fruit was observed in the treatments of 1/2S and 1/4S level of N fertilizer compared to 1 S level. In contrast, there was no statistic difference in the yield and quality with three levels of K fertilizer. Results indicate that the 1/2S level for N and 1/4S level for K fertilizer are effective and optimal for the melon plants grown under the fertigation culture in terms of increasing fruit yield and quality and reducing the cost of fertilizers.

• Korean Journal of Medicinal Crop Science
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• v.1 no.2
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• pp.125-128
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• 1993

This study carried out to know the growth characteristics and Co-production effect of leaf, newly developed stem and fruit by different harvest times. The dry matter yield of above growth part shown the highest at mid of July. Leaf dry matter, however, shown the highest at end of June and after that decreased drastically. The dry matter yield of newly developed stem increased gradually from early stage to harvest. Fruit set number of first branch was much higher than that of main stem and 2nd branch. The more leaf and newly developed stem harvest the less fruit yield obtained. When Co-production considered by economic yield, fruit yield with three times of leaf harvest shown the best production.

• Journal of Korean Society of Forest Science
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• v.111 no.4
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• pp.557-566
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• 2022

This study aimed to obtain basic data on high-quality fruit production and efficient cultivation of persimmon cultivar "Godongsi". In the second year of pruning, the number of fruits per tree according to the number of fruit-bearing mother shoots (300, 400, 500, and 700 [control] treatments) was 676.3, 786.0, 866.7, and 1238.7, respectively. Persimmon cultivar "Godongsi" had a decrease in number of fruits per tree and increase in fruit weight as the pruning intensity increased. The average fruit weight in the 300 treatment group was 212.2 g, which was 1.5 times heavier than that in the control. For a high-quality dried persimmon processing, the rate of grade L fruits (170 g<ｘ≤200 g) and over according to the number of fruit-bearing mother shoots was 86.9%, 48.6%, 33.5%, and 8.1%, respectively. The fruit grade of the pruned treatment group was significantly higher than that of the control. Based on the selling price of dried persimmon, the production amount was significantly higher in the 300 treatment than that in the control. When there were many fruits per tree, there was a decrease in quality and increase in cost of harvesting and processing. In conclusion, pruning is essential to increase the fruit quality (fruit weight and grade) of persimmon cultivar "Godongsi". Moreover, the suitable number of fruit-bearing mother shoots was 300.

• Journal of Bio-Environment Control
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• v.18 no.4
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• pp.420-424
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• 2009

This experiment was executed to investigate the effect of the carpenter bee as a pollinator on the fruit set increment of sweet pepper in summer hydroponics in the alpine area of Gangwon province, Korea. Where the number of fruit sets were increasing during the treatment of pollination by the carpenter bee, total yields during the whole growing period were not different. The number of seeds per fruit in the treatment of the carpenter bee increased more than that in the control by 7.3 percent increment, but the percentage of blossom-end rot increased. As fruit weight range of SS size (below 120g) decreased and that of L size (from 181g to 210g) increased by the pollination treatment, so the percentage of standardized products for the export to Japan improved. Therefore this result was effective for the fruit production of high quality for the export to Japan and it will be necessary for further study on the method of reducing blossom-end rot to be done.

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.438-446
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• 2019

The interest in mini watermelon (Citrullus lanatus) with small fruits weighing 2-3 kg has increased by the increasing trend in one-person households and consequent tendency to consume small meals. Watermelon grafting onto cucurbit rootstocks is a very effective way to control soil-borne diseases, such as Fusarium wilt; however, this practice negatively impacts the fruit quality. This study was conducted to investigate the growth, fruit set, and fruit quality of mini watermelon grafted onto wild watermelon accessions (Citrullus spp.) resistant to Fusarium wilt. Five watermelon accessions (Galactica, IT 208441, PI 482322, PI 500303, and PI 593358) were evaluated as rootstocks for the mini watermelon "Ministar". Non-grafted "Ministar" and "Ministar" grafted onto "Shintozwa" (Cucurbita maxima D. C. moschata D.) or "Bullojangsaeng" (Lagenaria leucantha) were used as controls. The roots of the transplants grafted onto "PI 593358" and "Shintozwa" weighed more than those on other rootstocks. Additionally, the transplants on "PI 593358" showed better growth and fruit set in the field than the other transplants. However, the total soluble solid contents and fruit quality indices of the transplants on "PI 593358" and "Shintozwa" were lower, whereas the total fruit quality index of those on "PI 482322" was higher. Thus, the wild watermelon accessions tested can potentially be used as basic germplasm for developing watermelon rootstocks instead of cucurbit rootstocks. The most promising accession for this purpose was found to be "PI 482322".

• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.334-342
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• 2016

In order to evaluate the modified installation methods of roof ventilation devices, derived from the previous experiment ('investigation into the optimum capacity of roof ventilation devices and their deployment'), the conventional and modified (improved) roof ventilation systems were installed in the single-span plastic greenhouse for growing oriental melons. The roof vents ($60{\varphi}$) and roof fans (maximum air capacity of $38m^3/min$) were installed in the spacing of 15m (FT, modified 'side vent+roof fan' ventilation) and 6m (TT, modified 'side vent+roof vent' ventilation) respectively on the roof of greenhouses for the modified roof ventilation treatments, and 20m (FC, conventional 'side vent+roof fan' ventilation) and 8m (TC, conventional 'side vent+roof vent' ventilation) for the conventional ones. The stem diameter, leaf blade lengh, petiole length, and leaf width were lower in the FT and TT treatments than those in the conventional treatments, FC and TC. Although the fruit weight and total yields were slightly lower in the FT and TT treatments, the marketable fruit ratio (%) were higher, as a result of increased fruiting ratio (%) in these treatments, than those of FC and TC. The marketable yields (kg/10a) in the FT and TT treatments were 8,391 kg/10a and 7,283 kg/10a, which were respectively 661 kg/10a and 487 kg/10a higher than those in the treatments of FC and TC. The modified installation methods of roof fan resulted in production of more female flowers and lower fruit drop ratio (%) compared to conventional meathods. In the treatment of the conventional ventilation with roof vent, the fruit weight, fruit length & width, and flesh thickness were higher than in other treatments, but there were no significant differences in the fruit width and flesh thickness among the treatments.

• Journal of agriculture & life science
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• v.45 no.5
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• pp.57-62
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• 2011

This study was conducted to determine the distribution of nitrogenous compounds to various tree parts and the extent of reserve accumulation in persimmon (Diospyros kaki) under various fruit-loads. This study also ascertained the proportion of storage nitrogen made available for the new growth the following year. On June 15, the fruit-load was adjusted to a leaf-fruit (L/F) ratio of 10, 20, and 30, and some trees were completely defruited. Between June 15 and November 11, the increase of total amino acids were greater with a high L/F ratio. The amino acids increased in the root were negligible at the 10-L/F ratio. Of the total amino acids increased during this period, the proportion distributed to the root was 64% in the 20-L/F, 18.5% in the 30-L/F, and 81% in the defruited trees, and the distribution to the fruits was 81% in 10-L/F, 12% in 20-L/F, and 35% in the 30-L/F trees. Leaf amino acids decreased in the 10-L/F trees. Total proteins increased in autumn were greater as the L/F ratio was higher. Total proteins were in the fruits the most, and the distribution to the permanent parts was decreased as the L/F ratio was decreased. At the L/F ratio of 30, 59% of the total proteins increased in the autumn was distributed to the fruits and 40% to the root. Leaf proteins decreased at 10 and 20 L/F ratios. During the new growth from April 10 to June 10 the following year, amino acids decreased in the old wood and 1-yr-old shoot, whereas proteins decreased only in the 1-year-old shoots. Amino acids and protein decreased by 540 mg and 610 mg, respectively, in the roots of the defruited trees. Total amino acid and proteins in the newly-grown parts were the most at 730 mg and 1290 mg, respectively, when defruited the previous year. They were the least at the 10-L/F ratio, being 120 mg and 400 mg, respectively.

• Journal of Bio-Environment Control
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• v.26 no.2
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• pp.56-63
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• 2017

This study was carried out to establish qualities of watermelon seedling (Citrullus lanatus) according to raising seedling period (RSP; 40, 45, 50, 55, 60, and 65 days) and was carried out to investigate growth characteristics after planting of the seedlings. In seedling qualities according to RSP, Plant height, stem diameter, leaf area of seedling with RSP 65 treatment were significantly increased. Fresh and dry weight in the above of corp showed a significant difference among the seedlings with RSP 40-45, RSP 50-60 and RSP 65 treatment, and that in of root were significantly higher in the seedlings with RSP 40, 45, 65 treatments than with other RSP treatments. S/R ratio was lower in the seedlings with RSP 40 and 45 treatments than with other RSP treatments. RSP affected to the leaf area and S/R ratio of seedling. After 11 weeks after planting of a various seedlings, except that height and node number of plant with 45 RSP treatment was lower than other RSP treatments, other growth characteristics were not significantly different amon RSP treatments. Leaf area, fresh weight, dry weight and S/R ratio were lowest in plant with RSP 65 treatment. Relative growth rate and net assimilation rate of planted watermelon tended to decrease and leaf area ratio was continuously increased until 9th week in the all treatments. The lighter and heavier fruit were produced in plants with RSP 40 and RSP 65 treatments (9.7 kg and 9.9 kg) and in RSP 50 and RSP 55 treatments (both 11.0kg), respectively. Fruit sugar contents was highest in fruit with RSP 45 treatment, and was lowest in RSP 50 and RSP 60 treatments. RSP showed a polynomial regression relation with the increment of fruit weight and the weight of harvested fruit. Considering the increment and weight of fruit, the most for RSP of watermelon seedling for planting were 50-55 days.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.179-187
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• 2016

This study was conducted to determine the impact of elevated temperature and $CO_2$ concentration based on climate change scenario on growth and fruit quality of pepper (Capsicum annuum L. cv. Muhanjilju) with SPAR (Soil Plant Atmosphere Research) chamber. The intraday temperatures of climate normal years fixed by $20.8^{\circ}C$ during the growing season (May 1~October 30) of climatic normal years (1971~2000) in Andong region. There were treated with 4 groups such like a control group (ambient temperature and 400ppm $CO_2$), an elevated $CO_2$ group (ambient temperature and 800ppm $CO_2$), an elevated temperature group (ambient temperature+$6^{\circ}C$ and 400ppm $CO_2$) and an elevated temperature/$CO_2$ group (ambient temperature+$6^{\circ}C$ and 800ppm $CO_2$). Compared with the control, plant height, branch number and leaf number increased under the elevated temperature and elevated temperature/$CO_2$ group. However, leaf area and chlorophyll content showed a tendency of decreasing in the elevated temperature group and elevated temperature/$CO_2$ group. The number of flower and bud were decreased in the elevated temperature and elevated temperature/$CO_2$ group (mean temperature at $26.8^{\circ}C$) during the growth period. The total number and the weight of fruits were decreased in the elevated temperature group and elevated temperature/$CO_2$ group more than the control group. While the weight, length and diameter of fruit decreased more than those of control as the temperature and $CO_2$ concentration increased gradually. This result suggests that the fruit yield could be decreased under the elevated temperature/$CO_2$ ($6^{\circ}C$ higher than atmospheric temperature/2-fold higher than atmospheric $CO_2$ concentration), whereas the percentage of ripen fruits after 100 days of planting was increased, and showed earlier harvest time than the control.