• Research in Plant Disease
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• v.15 no.1
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• pp.51-53
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• 2009

The fruit rot of watermelon (Citrullus lanatus) occurred sporadically in the farmers field at Chojeondong, Jinju city, Korea, in 2007. The typical symptom was water-soaked, brown on the fruit, and than infected fruits were mostly rotted. White mycelial mats were spread over lesions, and then sclerotia were formed on fruit and near soil line. The sclerotia were globoid in shape, $1{\sim}3\;mm$ in size and white to brown in color. The optimum temperature for mycelial growth and sclerotia formation on PDA was $30^{\circ}C$ and the hyphal width was $4{\sim}8{\mu}m$. The typical clamp connections were observed in the hyphae of the fungus. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii. This is the first report on the fruit rot of watermelon by S. rolfsii in Korea.

• Journal of Bio-Environment Control
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• v.13 no.3
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• pp.156-161
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• 2004

This study was conducted to investigate the effects of soil amendment with different characteristics on plant growth, fruit yield and quality of oriental melon for continuous cropping under protected cultivation. Humus layers in arable soil was disturbed because soil amendment from hillside to oriental melon field was continued to resolve problems for continuous cropping. Water potential and hardness of soil was decreased in sandy loam with lower clay contents compared with loam and silty clay. Leaf length and area, fresh and dry weight of plant at earlier growing stage were higher, but chlorophyll contents of leaves were dropped in sandy loam compared with silty clay soil. Fruit size and weight was higher in sandy loam, but soluble solid and color of fruit were increased in silty clay. Marketable and unmarketable yield and quantity of fermented fruit were the highest in sandy loam. Hardness and weight of fruit were decreased by longer storage period and soluble solids of fruit was peaked at 5 day after storage, but decreased by prolonged continued storage. Because of these results, soil characteristics of amendment to oriental melon field should be considered as an important factor for quality and yield of oriental melon.

• Korean Journal of Environmental Agriculture
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• v.35 no.4
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• pp.256-262
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• 2016

BACKGROUND: 'Shiranuhi' mandarin is one of the popular citrus cultivars in Jeju Island, Korea. However, the emergence of scion roots since the past few years has altered its flowering, fruiting, and quality. Girdling of branches is one of the methods of increasing flowering in citrus trees. METHODS AND RESULTS: This experiment was conducted to determine the effect of girdling on the flowering and yields of scion rooted 'Shiranuhi' mandarin hybrid. We selected normal trees without scion roots as controls. The trees with scion roots were divided into two groups: trees without girdling and with girdling on main branches. Each group contained five replications and the experiment was conducted in Gosan and Harye of Jeju Island. The scion rooted trees revealed severely decreased flowering and low flowering/leaf ratios; however, the leaf/fruit ratio significantly increased. But, girdling on main branches significantly increased flowering and the flowering/leaf ratio. In the scion rooted trees, yields dropped due to poor flowering; however, girdling of branches efficiently improved the yields of the trees. Fruit quality, fruit size, and fruit weight of scion rooted trees were low in comparison with the control, whereas girdling of the branches improved flowering and the fruit weight to some extent. No significant difference in soluble solid contents was observed. CONCLUSION: Girdling is an effective method to induce flowering of the scion rooted 'Shiranuhi' mandarin trees. In addition, yields of scion rooted trees were improved.

• Journal of Sericultural and Entomological Science
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• v.53 no.1
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• pp.50-54
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• 2015

Mulberry fruit is common to keep a frozen storage because of the very high water content. Because freezing-storing cost is generated before the processing or sales, farmers of mulberry fruit production are weighted in financial burden. In addition, mulberry fruit has difficulty in expanding consumption by made in the simple processed products like the mulberry jam, mulberry juice, mulberry enzyme, alcohol, etc. Recent, frozen fruits including frozen blueberries, frozen strawberries, frozen mango, frozen rich, frozen mulberry fruit has been started to sell in the large discount stores and convenience stores. However, there is restricted sales in only special place that have the frozen distribution facilities. So, for the income improvement and consumption promotion of mulberry farmers facing these difficult situations, we developed the processing method of semi-dried mulberry fruit using the vacuum freezing dryer. The frozen mulberry fruit which was stored below $-40^{\circ}C$ is to dry in a vacuum freeze dryer, at $30{\sim}35^{\circ}C$, 23 ~ 24 hours. Semi-dried mulberry fruit seperated respectively. It had soft texture, and maintained shape, size and flavor. In particular, semi-dried mulberry fruit can be stored at room temperature.

• Korean Journal of Plant Taxonomy
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• v.45 no.4
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• pp.353-361
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• 2015

Spatio-temporal variation in fruit set in orchids would affect long-term population viability and will influence genetic diversity over many generations. The aim of this study was to examine the breeding system of the nectariferous terrestrial orchid Epipactis thunbergii, to specifically determine levels of fruit set in terms of time and space under natural conditions. We examined pollination under natural conditions and conducted hand pollination experiments during a 2-year survey in four populations located along 1.5 km of coastal line in Jinguiri (rual village) [Jeollanam-do (province), southern Korea]. We found that, over a 2-year period, levels of percentage of fruit set were similar within patches of the four populations. By contrast, we detected significant differences in the percentage of fruit set among patches. We also found that plants with larger inflorescence size produced significantly more fruits than plants with fewer flowers. Over a 2-year period, the percentage of fruit set for E. thunbergii was similar but low (14.1%) compared to that averaged for eighty-four rewarding species (37.1%). However, an increase in fruit set was achieved by hand-pollinations: artificial self-pollination (90.5-95.2%), artificial geitonogamy (94.7-95.0%), and cross-pollination (artificial xenogamy, 91.3-91.4%). No emasculated flowers produced fruits and no automatic pollination was found in E. thunbergii. Our findings suggest that E. thunbergii is a self-compatible terrestrial orchid that depends on pollinators (insects) to achieve fruit set in natural habitats, and that local environmental conditions were similar over a period of 2 years in the study area. Our results also highlight the cryptic variation of fruit production in time, but more pronounced variability in space.

• Journal of Bio-Environment Control
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• v.24 no.2
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• pp.113-118
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• 2015

The objective of this experiment was to evaluate the effects of application wide plastic shelter (WPS) in the 'Campbell Early' grape. WPS was developed 30cm wider than standard plastic shelter (SPS; 210cm). Under the plastic shelter, the average daily temperature was $2{\sim}3^{\circ}C$ higher than ambient temperature, but WPS treatment was $0.5{\sim}1^{\circ}C$ higher than SPS treatment. However, relative humidity 15~20% lower than ambient and shown different result between two treatments annually. The occurrence of brown leaf spot disease caused by Pseudocecospora vitis on the vineyard decreased 55.6% (2012) and 17.2% (2013) under WPS than SPS. Grape bunches collected two harvest seasons (2012, 2013), were analyzed fruit quality (total soluble solid; TSS, titratable acidity; TA, berry weight, berry size). In 2012, grapes had no differences in the quality of two treatments, but in 2013, significantly increase $0.4^{\circ}Bx$ of TSS and decrease 0.8% of TA on the WPS than SPS. It suggests that the application WPS reduced the incidence of brown leaf spot disease annually, and then affect to the fruit quality.

• Food Science and Preservation
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• v.21 no.3
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• pp.365-372
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• 2014

Imported Valencia oranges were evaluated to determine the relationship between the fruit size and its quality. The orange size was classified into three groups on a commercial basis: small ($140{\sim}160g/113{\pm}5$ fruit/box), medium ($190{\sim}220g/88{\pm}5$ fruit/box), and large ($250{\sim}280g/72{\pm}5$ fruit/box). The physicochemical and sensory properties were analyzed to evaluate the orange quality. No significant difference in the peel thickness and flesh ratio was detected across the fruit sizes. The juice yield of the medium-sized orange and the TSS/TA ratios of the medium-sized and large oranges showed the highest value, respectively (p<0.05). The large orange had the highest vitamin C content, which was positively correlated with both its DPPH and ABTS radical scavenging abilities (p<0.05). In the sensory evaluation of the fruits and their juice, the scores for sourness and overall preference were significantly higher in the medium-sized and large oranges than in the small ones. The total soluble solids, total acidity, TSS/TA ratio, and reducing sugar content were significantly related to the sensory properties. Finally, the quality and sensory properties were considered superior in the medium-sized and lager Valencia oranges. Further studies on the effects of the variety and origin of Valencia oranges on their quality and sensory properties are required.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.486-491
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• 2015

In this study, we evaluated the differences in fruit development and quality indices of fruits subjected to blossom thinning before full bloom in 'Hanareum' and 'Niitaka' pears (Pyrus pyrifolia Nakai). We carried out a thinning treatments at 5 days before full bloom, targeting the blossoms at the 1st and 2nd position (T1) or the blossoms at the 6th and 7th position (T2) from the basal part of the flower cluster in both cultivars. Blossom thinning treatments increased the average fruit weight of early-season Asian pear 'Hanareum' up to 10.5% (T1) and 11.0% (T2) at harvest time (110 days after full bloom). The mid-season 'Niitaka' pear showed increased fruit weight of up to 12.6% (T1) and 16.8% (T2) at harvest time (170 days after full bloom). Moreover, these treatments increased the production rate of bigger sized fruits in both cultivars. Removal of blooms also affected fruit quality indices; the bloom-thinned fruits showed higher soluble solids contents (about $1^{\circ}Brix$) and higher skin color redness ($a^*$) especially in 'Niitaka' pears when compared to the non-thinned controls. Overall, the treatments increased the fruit size and weight as well as fruit quality including soluble solids and skin color. Bloom thinning treatment targeting the 6th to 7th blossom from the basal part of the flower cluster may be recommended as the practical thinning method in Asian pear 'Hanareum' and 'Niitaka'.

• Korean Journal of Plant Resources
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• v.33 no.6
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• pp.624-637
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• 2020

High-quality and high-phytonutrient watermelon fruits have strong market opportunities besides their health related benefits. Hence, investigating quality and nutritional related traits of watermelon genetic resources could provide important baseline data in breeding for increased lycopene content thereby increasing the marketability of watermelon. To this end, we have examined some fruit morphological traits and lycopene content of 105 genetic resources. Seeds, originally obtained from 22+ countries, were obtained from the National Agrobiodiversity Center, Jeonju, South Korea, grown in an experimental field and harvested at a fully mature stage. The size of pistil scar (SPS), the width of stripes (WS), weight of fruit (WF), length of fruit (LF), width of fruit (WIF), the thickness of pericarp (TP), soluble solids content (SSC), fruit shape in longitudinal section, ground color of skin, the intensity of the green color of skin, fruit shape at the apical part, grooving distribution, conspicuousness of stripes, and main color of the flesh were recorded on the field and inside laboratory and the lycopene was measured using spectrophotometric and HPLC methods. Watermelon fruits have shown a diverse morphological characters. Red and pink fleshed fruits dominated in the entire collections. Fruits with higher thickness of rind were found to exhibit less soluble solid content (SSC). Korean origin fruits were characterized by intermediate SSC while the United States of America (USA), Russia (RUS), Tajikistan (TJK), Turkmenistan (TKM), Taiwan (TWN), and Uruguay (URY) originated fruits had the highest SSC. The lycopene content varied between 41.37 and 182.82 ㎍/g, 2.81 and 163.72 ㎍/g, and 3.54 and 255.47 ㎍/g using HPLC, UV-Vis spectrophotometer, and microplate reader spectrophotometer, respectively. Red- and pink-fleshed fruits had the highest levels of lycopene content compared to the yellow- and orange-fleshed. Lycopene content had a significant positive correlation with SSC, however, no correlations were detected between lycopene and other quantitative fruit morphological characters. Our study demonstrated high diversity exists in fruit morphological traits and lycopene content of the germplasm collections which provide beneficial baseline data for a future breeding program and utilization of watermelon germplasm collections in gene banks for the maintenance and improvement of the current levels of production, marketability, and health-related benefit of watermelon fruits.

• Food Science and Preservation
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• v.21 no.4
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• pp.468-472
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• 2014

The effect of pre-storage treatments was investigated to control the occurrence of fruit skin stain in 'Niitaka' pears. The incidence of fruit skin stains was significantly reduced when the fruits were stored in paper bags with a yellow inner color, compared to when they were stored in paper bags with blue and red inner colors. Additionally, the pear fruits that were harvested seven days earlier than their optimum maturity date developed less fruit skin stains in cold storage and retained their quality. Storage in polyethylene (PE) bags did not control the occurrence of fruit skin stains as effectively as did bag-free storage or storage in calcium-coated bags. The dipping of the pear fruits in a chlorine dioxide and calcium solution was highly effective in reducing the fruit skin stains compared to when they were not dipped or when they were dipped only in distilled water. In particular, a 1,500 times diluted solution of sodium dichloroisocyannurate (NaDCC) reduced the incidence of fruit skin stains and the size of the lesions. No stain was observed on the skin of the fruit with a water content lower than 67.7% (w/v) during its storage. In conclusion, packaging pear fruits in bags with an inner calcium coat and dipping them in a chlorine dioxide, calcium, or NaDCC solution can effectively reduce their skin stains during their storage.