• Korean Journal of Plant Resources
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• v.30 no.5
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• pp.565-570
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• 2017

In a plumcot 'Harmony' cultivar, which is an interspecific hybrid between plum and apricot, canopy occupation and productivity according to tree training system, Y shape with no trellis (YNT) and Y-palmette with trellis (YPT), were compared. According to the survey results for 5 years of planting, tree growth was similar in two training systems. However, canopy occupation and fruit yield of YPT were significantly higher than those of YNT. The fruit weight and sugar content were not significantly different between two systems. The fruit drop rate tended to be lower in YPT than in YNT. From the above results, it is expected that the YPT type will contribute to the increase of canopy occupation and fruit yield and reducing the fruit drop rate compared to the YNT.

• Journal of Environmental Science International
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• v.27 no.8
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• pp.631-639
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• 2018

A Cultivation method to minimize the damage caused by high temperatures was studied by investigating the effects of groundwater cooling treatment on the growth, yield, and quality of strawberries. In the groundwater cooling treatment, the daily average temperature of the rhizosphere was reduced from $26.9^{\circ}C$ to $24.9^{\circ}C$. The root length increased by 0.3-9.2 cm, depending on the cultivar and growth period. The leaf number, leaf area, leaf length, leaf diameter, and plant height also increased, especially in the cultivars 'Seolhyang' and 'Maehyang', resulting in higher fresh and dry weights. The number of fruit per plant increased from 7.7 to 12.5 in 'Seolhyang', and the fruit weight increased by 0.3 g in 'Seolhyang' and 1.3 g in 'Maehyang'. The fruit hardness increased, but no significant difference in fruit coloration was observed. The sugar content of the fruit was improved by $0.2-0.3^{\circ}Brix$. Therefore, groundwater cooling of the rhizosphere was effective in improving the growth and productivity of strawberries under abnormally high temperature conditions and can be considered a cost-efficient cooling system.

• Horticultural Science & Technology
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• v.19 no.1
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• pp.66-70
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• 2001

'Mansoo' is a late-season pear cultivar with extra large and high quality fruit of long storability, which was released by National Horticultural Research Institute in 1995. The cultivar originated from the cross between 'Danbae' and 'Okusankichi' at Suwon in 1978, had been under regional adaptability test at nine areas in the name of 'Wonkyo Na-15' for 4 years since 1992. It was vigorous in tree growth and upright in tree shape. Its flower bud is easily maintained, resulting in higher productivity than 'Danbae' and 'Okusankichi'. It bloomed a day later than 'Niitaka', and showed cross-compatibility with 'Niitaka', 'Chojuro' and some other varieties. Harvesting time of 'Mansoo' is late October in Suwon. The fruit shape is oblate and skin color is light yellowish brown. The fruit weighed 600-700 g and has 12-13% soluble solids content. The flesh is soft, juicy, and has negligible grit. It is resistant to black leaf rot (Alternaria kikuchiana Tanaka).

• Korean Journal of Agricultural Science
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• v.49 no.3
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• pp.421-430
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• 2022

Crop load management in apple trees is important for achieving optimum productivity and crop value. Hence, we investigated the influence of different crop loads on the fruit quality, mineral content, and yield of the 'RubyS' apple variety. After 4 weeks of full bloom, the crop load was adjusted by hand thinning to different (5, 10, and 15 fruits·cm^-2) trunk cross-sectional areas (TCSA), representing low, medium, and high crop loads. The low crop load increased the fruit size and weight, the development of the red-blushed area, and the peel color a^* at harvest; however, it reduced the total number of fruits·tree^-1 and yield compared with that of the other crop loads. The medium crop load improved the fruit weight, flesh firmness, and soluble solids content and reduced the fruits·tree^-1 but did not affect the fruit size and yield. However, there were no significant differences in the titratable acidity and starch index among the crop loads. The fruit mineral content (phosphorus and potassium) was higher in the low and medium crop loads compared to the high crop load. However, the nitrogen, calcium, and magnesium contents in the fruits were not affected by the crop loads. Overall, this study suggests that a low crop load improves the fruit size and weight, but its effect on the quality and fruit mineral content is similar to that of a medium crop load. Therefore, the optimum crop load level for the 'RubyS' apple trees was approximately 10 fruits·cm^-2 TCSA.

• Korean Journal of Environmental Agriculture
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• v.41 no.3
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• pp.158-166
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• 2022

BACKGROUND: Kiwifruit is a fruit tree with relatively small cultivation area in Korea and researches on its soil and physiology are very limited compared to those on cultivar development. Therefore, there are limited information for farmers to cope with the reduction in productivity due to various physiological disorders and premature aging. This study was conducted to investigate the soil and leaf chemical properties, and fruit characteristics, which will be used as basic data for stable kiwifruit orchard soil management. METHODS AND RESULTS: The soil and leaf chemical properties, and fruit characteristics were investigated for two years in 16 kiwifruit orchards growing 'Hayward' (Actinidia deliciosa) in Jeollanam-do and Gyeongsangnam-do. Soil and leaf samples were collected in July and fruit quality was investigated by harvesting fruits about 170 days after full bloom. The average soil chemical properties of kiwi orchards were generally higher than the recommended level, except for pH, and especially, the exchangeable potassium reached about 300% of the recommended level. The proportions of orchards that exceeded the recommended level of soil chemical properties were 63, 31, 100, 69, 94, 88 and 69% for pH, EC, organic content, available phosphate, and exchangeable potassium, calcium and magnesium, respectively. Thirty-three percent of orchards had more than 100 mg/kg of nitrate nitrogen in soil. Available phosphate in soil showed a significantly positive correlation with leaf nitrogen, phosphoric acid and calcium content, but showed a significantly negative correlation with leaf potassium content. The magnesium content in the leaves was significantly correlated with soil pH. The highest fruit weight was observed in about 25 g/kg of leaf nitrogen content which could be attained when plants were grown on the soil containing about 100 mg/kg of nitrate nitrogen content. The average soluble solids content among 16 orchards was 9.58 °Brix at harvest and 13.9 °Brix after ripening, which increased about 45%, and the average fruit weight was about 110 g. CONCLUSION(S): For fruit quality, fruit soluble solids (sugar compounds) content was significantly correlated with leaf potassium content, fruit hardiness with leaf total nitrate, calcium and magnesium, and fruit titratable acidity with leaf magnesium; however, leaf calcium and magnesium negatively affect the soluble solids contents in fruits.

• Horticultural Science & Technology
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• v.35 no.4
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• pp.393-401
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• 2017

One-year old pear (Pyrus pyrifolia L.) trees of a new commercial cultivar 'Manpungbae', recently developed in South Korea, were planted in 2001 (planting year 1) and trained to four trellis systems: Y-trellis, Y-II-trellis, pergola, and vase-pergola. To evaluate training systems in the local area (southern Korea), tree growth responses were compared for each trellis system from planting years 3 to 8. For trees trained to Y-trellis and pergola systems, a high proportion of land covered by tree canopy was maintained over the study duration, with 70-80% coverage in year 8. Eight-year cumulative yield per tree was increased in the vase-pergola system with a low planting density and an additional scaffold. Compared with other systems, cummulative yield use efficiency was greatest in Y-II-trellis and pergola systems in years 5 and 8. Compared with Y-II-trellis and vase-pergola systems, the 8-year cumulative yield per hectare was two fold greater for trees trained to the Y-trellis (103 tons) and pergola systems (101 tons). Use of the pergola system improved average fruit weight and fruit soluble solid contents, as well as net income in year 8. Given that we observed reduced fruit productivity and increased labor hours (pruning and orchard work), we consider the Y-trellis and pergola systems to be less valuable trellis systems than the others evaluated.

• The Korean Journal of Mycology
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• v.36 no.1
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• pp.41-44
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• 2008

Studies were made to investigate the difference of the shiitake productivity according to the use of sawdust and liquid spawn on middle-temperature type strain. Treatments inoculated with sawdust spawn have shown that yields were dispersed according to flushing periods and fruit-bodies occurred sporadically on medium. However, treatments inoculated with liquid spawn have shown that yield was relatively concentrated at 1st flushing period and fruit-bodies were densely occurred on medium. At total yield and the number of fresh fruit-bodies until seventh flushing, treatments inoculated with liquid spawn were more than those inoculated with sawdust spawn. Also, biological efficiency (B.E.) of inoculation with 20 ml liquid spawn which produced 30% of the medium weight was highest as 69%, but biological efficiency of inoculation with 10 g sawdust spawn was lowest as 42%. And, although rate of fruit-bodies over 10 g in total yield was high on treatments inoculated with sawdust spawn, amounts of fruit-bodies over 10 g were not different among treatments.

• Journal of Bio-Environment Control
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• v.32 no.4
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• pp.475-483
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• 2023

This study was conducted to determine the optimal irrigation starting point by analyzing tree growth, physiological responses, fruit quality, and productivity in peach orchards. Seven-year-old 'Kawanakajima Hakuto' peach trees were used in an experimental field (35°49'30.4"N, 127°01'33.2"E) located within the National Institute of Horticultural and Herbal Science located in Wanju-gun, Jeollabuk-do. The irrigation starting point was set with four levels of -20, -40, -60, and -80 kPa from June to September 2022. While there were no significant differences in increase of trunk cross-section area and leaf area among treatments, shoot length and diameter decreased in the -80 kPa and -20 kPa treatments. The photosynthetic rate measured in August was highest for -60 kPa (17.7 μmol·m^-2·s^-1), followed by -40 kPa (15.6 μmol·m^-2·s^-1), -20 kPa (14.5 μmol·m^-2·s^-1) and -80 kPa (14.0 μmol·m^-2·s^-1). SPAD value measured in May and August was lower in the -80 kPa and -20 kPa treatments than in the -60 kPa and -40 kPa treatments. The harvest date reached three days earlier in the -20 kPa treatment compared to other treatments. The fruit weight was highest in the -60 kPa (379.1 g), followed by -40 kPa (344.0 g), -80 kPa (321.0 g) and -20 kPa (274.9 g). Firmness was the lowest in the -20 kPa treatment. The soluble solid content was highest in the -60 kPa treatment (13.3°Bx).The ratio of marketable fruits was highest in the -60 kPa treatment (50.7%) and lowest in the -80 kPa treatment (23.4%). In conclusion, we suggest that setting the irrigation starting point at -60 kPa could improve the fruit quality and yield in peach orchards.

• Korean Journal of Breeding Science
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• v.41 no.2
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• pp.126-129
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• 2009

The new Rubus coreanus Miq. variety, 'Doo-Ryun', was selected from 227 clones of the clone bank. This breeding was progressed to select the superior variety for high productivity from 1998 to 2005. To evaluate the clones, characteristics of a fruiting lateral and a ripe fruit were investigated. 'Doo-Ryun' was finally selected through selection of three times and stable trial at four different regions. 'Doo-Ryun' has specific morphological characteristics that are fewer thorn in lateral and strong glossiness of leaf upper side than contrast clone. The flowing and fruiting characteristics of 'Doo-Ryun' shown that the number of flower per fruitng lateral, the number of fruit per fruiting lateral, fruit weight and yield per individual were 17.2, 16.9, 1.73g and 4.50kg, respectively. Also, their selection effects were evaluated as 103.6%, 107.6%, 140.6% and 155.7% compared to the mean of whole clones in the clone bank, respectively.

• Korean Journal of Environmental Agriculture
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• v.39 no.4
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• pp.352-359
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• 2020

BACKGROUND: The mulberry cultivars 'Daeshim' and 'Shimgang' were developed in RDA in 2014 and 2017, respectively. 'Daeshim' yields a fruit size bigger than that of other varieties and has a productivity of over 70%, whereas 'Shimgang' has a high yield and a special characterization against the mulberry popcorn disease. In our study, a compositional comparison of these popular cultivars in Korea was undertaken to explore the nutrient profiles of mulberry fruit and promote the development of the rich minerals and flavonoids in mulberry fruit as performing each other irrigation time. METHODS AND RESULTS: These two cultivars were collected from the Sericulture and Apiculture Division, RDA, in Korea to investigate their amounts, weights, minerals, and flavonoid content using each other instrument. After 6 h of irrigation treatment, the amount of fruit (kg/tree) from Daeshim and Shimgang increased by 17.5 and 15.2 kg/tree, respectively. The total flavonoid content from Daeshim and Shimgang was determined to be 132.9 mg and 36.3 mg, respectively, after the 6 h irrigation treatment. CONCLUSION: Appropriate irrigation treatment methods such as water scheduling and volume will help increase fruit quantities and farmer incomes. It would be interesting to conduct further in-depth research on these fruits so that consumers can benefit from them as a food additive.