• Journal of Bio-Environment Control
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• v.18 no.1
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• pp.40-45
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• 2009

The experiment has investigated the effects of growth, yield, fruit quality and cation absorption of strawberry 'Akihime' in different $NO_3-N:NH_4-N$ ratio in nutrient solution. $NO_3-N:NH_4-N$ ratios were 5.5:0, 4.0:1.5 and $3.0:2.5me{\cdot}L^{-1}$. As the ratio of $NH_4-N$ increased, pH was decreased by $5.0{\sim}6.0$ and EC sustained $0.8{\sim}1.0dS{\cdot}m^{-1}$ during experiment. Though in high $NH_4-N$ ratio of $3.0:2.5me{\cdot}L^{-1}$, the absorption of cations(K, Ca and Mg) was not inhibited. Treatment in contained $NH_4-N$ showed a tendency of increasing of petiole length and leaf width. The fruit length, fruit width, fruit weight and soluble solids were not significantly different. Yield per plant was lowest in $4.0:1.5\;me{\cdot}L^{-1}$, of $NO_3-N:NH_4-N$ ratio. Malformation fruit has not shown during the whole growth period.

• Horticultural Science & Technology
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• v.31 no.4
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• pp.423-428
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• 2013

Although closed soilless culture is useful for saving water and fertilizers with minimizing environmental pollution, adequate management of nutrient solutions is still not stabilized in greenhouse cultivation. In order to investigate the problems occurred in closed soilless culture of Paprika (Capsicum annuum L., cv. Fiesta), we compared ion balance, fruit yield, and the water and fertilizer use efficiencies in the closed system with those in the open system. The plants were grown in rockwool culture with a nutrient solution of EC $2.5dS{\cdot}m^{-1}$. After 4 weeks of treatment, individual ratio of $NO{_3}^-$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ to total ion concentrations ($meq{\cdot}L^{-1}$) decreased from the initial value, especially the biggest decrement was observed in $K^+$, and on the other hand, $SO{_4}^{2-}$, $Cl^-$, and $Na^+$ were accumulated in the closed system. Yields after four-time harvests were 19% higher in the open system than in the closed system. Total volume of water used per unit area ($m^2$) in the open system was 20% higher, but the total water use per fruit was not significantly different between the two systems, while t total fertilizer use per fruit was 78% higher in the closed system. Amount of marketable fruits was not significantly different between the two systems. We concluded that the increase in $K^+$ supply and the replenishment of recycled nutrient solution every four weeks were required for preventing the imbalance or depletion of nutrients in the close soilless culture of paprika plants to get more balanced nutrient composition during whole cultivation period.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.552-560
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• 2010

$GA_{4+7}$+BA, a plant growth regulator for induction of feathering in young apple tree and increasing fruit size, was applied by various methods on 'Gala'/M.9 apple trees in high density orchard for 4 years to investigate its effect on fruit and shoot growth. $GA_{4+7}$+BA($80-300mg{\cdot}L^{-1}$) increased fruit length, fruit weight, and L/D ratio regardless of application methods, but it did not affect soluble solid content, acidity, leaf area, and chlorophyll. Seed number was not affected by $GA_{4+7}$+BA application, however, more immature seeds was observed in treated 'Gala' fruit. Shoot growth was increased when spraying $GA_{4+7}$+BA at tree crown but not affected when spraying at fruit directly. More significant fruit growth was observed when $GA_{4+7}$+BA was applied on the fruits between late of May and early of June when fruit cell division ended; however, high concentration of $GA_{4+7}$+BA resulted in lower fruit storability because of lower firmness. Hence, more attention should be paid when applying high concentration of $GA_{4+7}$+BA to small sized fruit cultivars like 'Gala'.

• Journal of Bio-Environment Control
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• v.17 no.4
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• pp.306-311
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• 2008

Proper tree vigor and crop load were determined for 'Fuji'/M.9 apple trees in high density planting system from 2001 to 2003. Leaf/fruit ratio was highly correlated to mean fruit weight (y=1.715x+205.02, $R^2=0.66^{**}$) and yield (y=-35.l56x+5963.7, $R^2=0.44^{**}$). In addition, there was a significant correlation between the number of leaves per tree and mean fruit weight. However, crop load did not affect tree growth, soluble solids content of fruit, and Hunter a value. To harvest the fruits heavier than 300 g without biennial bearing, it was appropriate to crop 55 to 64 fruits in a tree with 55 leaves per fruit of adult tree. The good indices for proper tree vigor could be 20 to 25 cm of mean shoot length and above 95% of shoot termination rate. Moreover, no secondary growth and 20 to 30% of spur formation could be the indices for highly productive tree vigor.

• Journal of Nutrition and Health
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• v.42 no.4
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• pp.327-337
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• 2009

University students tend to have various dietary problems including undesirable dietary behaviors, inadequate intakes of nutrients and biased habits of liquid consumption. This study was conducted to find dietary behaviors (n = 357) by questionnaire survey and to examine dietary nutrient intakes (n = 60) and liquid consumption (n = 853) by food record method for 3-days among university students attended in K University of Chungnam province in Korea. Most subjects lived in the dormitory or self-boarding house, and they skipped breakfast most frequently and took breakfast most irregularly among three meals. Dietary mean intakes of energy, Ca, vitamin B2 and folate were lower than the KDRI (37-85%), and those of males were poorer than those of females. Ratios of energy intake among three meals and snacks were not distributed evenly, so the mean energy intake from snacks was higher and that from breakfast was lower than the ideal ratio, respectively. Daily mean consumption of liquid was 1,526.4 mL/d for males and 1,151.5 mL/d for females, and these intakes were more than the KDRI (1,300 mL/d for males and 1,100 mL/d for females). However, their sources of liquid consumption were not desirable because alcohol, soda, juice of fruit or vegetable and beverage mixed with fruit juice and/or vegetable juice were major sources of liquid as well as drinking water. These findings show that university students have poor dietary behaviors including frequent skipping of breakfast, irregularity of meals, inadequate intakes of nutrients and undesirable pattersirablliquid consumption including high portion of alcohol and soda as alliquid source, and these trends were stronger for males than for females. Therefore, we should endeavor to correct their meal problems id ated to dietary behaviors, nutrient intakes and liquid consumptions through nutrition education.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.459-469
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• 2015

The effects of elevated spring temperatures on the growth and fruit quality of the mandarin hybrid 'Shiranuhi' [(Citrus unshiu ${\times}$ C. sinensis) ${\times}$ C. reticulata] were investigated in plastic greenhouses, to develop a cropping system to improve the quality of the fruit and increase the income of growers on Jeju Island, South Korea. Under conditions of elevated temperature I ($25/15^{\circ}C$, day/night) and elevated temperature II ($28/18^{\circ}C$, day/night) during early spring, budburst was advanced by 11 and 15 d, and full bloom by 22 and 45 d, respectively, compared to those of the plants grown at ambient air temperature in a plastic greenhouse. Elevated temperatures decreased the number of spring shoots but increased mean spring shoot length and leaf area. Growing 'Shiranuhi' trees at elevated temperatures resulted in increases in mean fruit weight and fruit L/D ratio (> 1.0). In addition, fruit color development was significantly advanced in trees grown under elevated temperatures during early spring, which allowed the fruit to be harvested 1-2 months earlier than trees grown under ambient air temperature. Fruit soluble solids content (SSC) and titratable acidity (TA) at harvest were similar between elevated temperature I and ambient air temperature, but were significantly higher than at elevated temperature II. Considering fruit quality, harvest time, and yield, the elevated temperature treatment regime of $25/15^{\circ}C$ (day/night) during early spring could be useful for cultivation of the mandarin hybrid 'Shiranuhi' to increase the income of growers.

• Horticultural Science & Technology
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• v.16 no.1
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• pp.27-29
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• 1998

Artificial pollination (AP) and gibberellin A4+7 plus benzyladenine (promalin) were applied alone and together. AP was applied at 10% flowering time with 'Senshu' pollen (Malus domestica cv. Senshu). 12mg/L promalin was applied at 0, 10 and 20 days after falling of central flowers, respectively. In promalin treatment with or without AP application methods, fruit length, weight and length/diameter (L/D) were higher than those of control and AP. However, in AP and AP+ promalin application, the number of seeds and seed weight were higher than those of control and promalin. In AP+ promalin treatment, 78.6% fruits showed their uniform fruit shape and so significantly enhanced fruit uniformity compared to other treatments. Also cortex and core thickness of fruits were greater at the apex than that of other treatment. Fruit with L/D ratio over 0.87 were highly produced by applications of AP+promalin and promalin than control and AP only. 'Fuji' apples in good shape can be produced by using of AP + promalin together.

• Journal of Bio-Environment Control
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• v.19 no.3
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• pp.171-176
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• 2010

To investigate the effect of leaf removal on enlargement and coloring of persimmon fruits (Diospyros kaki L. cv. 'Fuyu'), four treatments control (0%), 20%, 50%, and 100% depend on leaf removal of fruit bearing branch were applied to persimmon trees. Sunlight intensities around fruits with treatments depend on removal level, compared with natural sunlight intensity (100 percentage level), was 7.9%, 13.6%, 16.4%, and 30%, respectively. Hunter $a^*$ of the fruit with control and 20% removal treatments to harvest season increased continuously. $Chroma^*$ of the fruit since the removal treatments of leaves increased continuously in all treatments, but from seventh week that had a decreasing tendency. The fruit weight and diameter were significantly heavy and short in treatments with 100% removal level. L/D ratio of the fruits had a significant difference between control and the other treatments. Soluble solids of the fruits lowed significantly in treatment with 50% removal level. Hunter $a^*$ of the fruits was better in treatments with control and 20% removal levels, Hunter $b^*$ and $Chroma^*$ lowed significantly in treatment with 20% removal level. $\beta$-Carotene and lycopene concentration of the fruits lowed in treatment with the higher of removal level, total chlorophyll contents had the opposite tendency to the pigments. All results considered, removal level of leaves around fruit on bearing branch in fruit maturation stage had effect on fruit coloring improvement.

• Korean Journal of Plant Resources
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• v.30 no.1
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• pp.101-109
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• 2017

For analysis of the relationship among blueberry cultivars, the growth period and morphological characteristics were investigated in 28 blueberry cultivars, and cluster analysis using the SAS program was conducted based on the morphological data. The harvest period was later and longer in rabbiteye blueberry cultivars (Austin, Brightwell, Powderblue, Southland, Tifblue) than in highbush blueberry cultivars. The L/D ratio of flower was more than 2.0 in the Austin, Brightwell, Powderblue, Southland, Tifblue, and Brigitta cultivars, and this could be disadvantageous for pollination. The 28 blueberry cultivars were classified into two groups by the cluster analysis based on growth period and morphological characteristics. Group I included rabbiteye blueberries and Group II included highbush blueberries. However, the northern, southern, and half-highbush blueberry cultivars were not differentiated.

• Korean Journal of Organic Agriculture
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• v.18 no.1
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• pp.63-74
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• 2010

The present study was carried out to evaluate the effects of organic liquid fertilizer (OLFs) fertigation on the growth and fruit quality of hot pepper (Capsicum annuum L.) cv. 'Nokkwang (Seminis Korea)'. Treatments were given with control (chemical feritilzer), OLF I(fowl dropping : fish meal : soybean meal, 2:1:1), OLF II(fowl dropping : bone meal : soybean meal, 2:1:1), OLF III(fowl dropping : bone meal, 1:1), and OLF IV(fowl dropping : rice bran : soybean meal, 2:1:1). The composition ratio of OLF based on weight to weight. The pH and EC of OLFs according to different material and compositions ranged from 6.5 to 6.8, and from 2.91 to $3.69dS{\cdot}m^{-1}$, respectively. The C/N ratio was the highest as 5.75 in OLF Ⅳ, and there was no difference among the treatments in C/N ratio of the exception of OLF IV. In OLF IV total fruit weight was the highest as 1,558g per plant and total fruit number increased as 23.7% compared to control. The content of capsaicin in the ripened pepper increased with OLF I and II treatments, and decreased with OLF III and IV treatments compared to control of $662mg{\cdot}kg^{-1}$, but the soluble solid content was the highest with OLF IV treatment as $10.0^{\circ}Brix$.