• Korean Journal of Soil Science and Fertilizer
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• v.44 no.4
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• pp.575-580
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• 2011

The cultivation of once-over harvest pepper cultivars might be very valuable to Korean farmers who still depend on traditional hand-harvesting method. Thus, we conducted this experiment to obtain important information for enhancing the productivity of once-over harvest red pepper fruits by supplying several nutrient-controlling and growth-regulating chemicals, such as $KH_2PO_4$, $SiO_2$ and 2-chloroethylphosphonic acid (ethephon). Adequate fertilization was provided in each treatment plots. In this study, two once-over harvest pepper cultivars, Saengryeg No. 211 and 213 (SR 211 and SR 213), and one regular piecemeal harvest pepper cultivar, Kangryegdaetong (KRDT), were cultivated to evaluate the productivity of pepper fruit as affected by above chemicals. The distribution of macro- and micro-nutrients in pepper fruits among the cultivars were different in term of N, B, Cu, and Fe concentrations. In particular, the concentration of B in SR 213 was about 2 times higher than that in SR 211 and KRDT. However, overall red pepper productivity of SR 211 was markedly higher ($2.91{\sim}3.38Mg\;ha^{-1}$) than that ($1.68{\sim}2.37Mg\;ha^{-1}$) of SR 213. Also, the productivity of matured red pepper was significantly influenced by the treatments of $KH_{2}PO_{4}$, $SiO_2$ and ethephon. The yield indices for matured red pepper fruits were the highest with the treatment of $KH_2PO_4$ or $SiO_2$ with ethephon, which were 113~116% for SR 211 and 147~150% for SR 213. Thus, the applications of $KH_2PO_4$ or $SiO_2$ with ethephon would be suggested to enhance the productivity of matured red pepper fruit.

• Journal of Nutrition and Health
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• v.17 no.2
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• pp.108-112
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• 1984

Quality characteristics of fruits and vegetables were investigated by physical, chemical and sensory evaluations. Firmness of tomato fruits tended to be reduced as their maturity or ripeness stage progressed. Sensory evaluation revealed that raw tomatoes were the most acceptable at pink or light red stage. Specific gravity was highly correlated with mealiness. Emphasis was placed on the basic study forming the foundation of national quality standards of raw fruits and vegetables.

• Korean Journal of Environmental Agriculture
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• v.39 no.4
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• pp.312-318
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• 2020

BACKGROUND: Photoreversibility, a reversion of the inductive effect of a brief red light pulse by a subsequent far red light pulse, is a property of photo responses regulated by the plant photoreceptor phytochrome B. Plants use photoreceptors to sense photo signal and to adapt and modify their morphological and physiological properties. Phytochrome recognizes red light and far red light and plays an important role in regulating plant growth and development. METHODS AND RESULTS: The reversal responses of growth and fruiting characteristics were investigated to increase the yield of oriental melon (Cucumis Melo L. var. Kumsargakieuncheon) by means of controlling light quality in a plastic house. Red (R:660nm) and far red (FR:730nm) lights were subsequently irradiated on the whole stems and leaves of the oriental melon plant during growing periods, using red and far red LEDs as light sources, from 9:00 PM daily for 15 minutes. The intensities of R and FR light were 0.322-0.430 μmol m-2s-1 and 0.250-0.366 μmol m-2s-1, respectively. Compared to R light irradiation, combination of R and FR light irradiation increased the length of internode, number of axillary stems, number of female flowers, and fruit number of oriental melons. The results of treatment with R were similar to R-FR-R light irradiation in terms of length of internode, number of axillary stems, number of female flowers, and number of fruits. When FR treatment was considered, R-FR and R-FR-R-FR light irradiation had similarities in responses. These reversal responses revealed that oriental melon showed a photoreversibility of growth characteristics, flowering, and fruiting. CONCLUSION: These results suggested the possibility of phytochrome regulation of female flower formation and fruiting in oriental melon. The fruit weight of the oriental melon was the heaviest with the R light irradiation, while the number of fruits was the highest with the FR light. With the FR light irradiation, the fruit weight was not significantly higher compared to that of the control. Meanwhile, the yield of oriental melon fruits increased by 28-36% according to the intensities of the FR light due to the increases of the number of fruits.

• Horticultural Science & Technology
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• v.31 no.1
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• pp.56-64
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• 2013

Recent unusual weather due to global warming causes shortage of daily sunlight and constitutes one of the primary reasons for agricultural damages. LED light sources are frequently utilized to compensate for the shortage of sunlight in greenhouse agriculture. The present study is aimed at evaluating formations of phytochemicals as well as growth characteristics of mature strawberry fruits ('Daewang' cultivar) during cultivation in a closed growth chamber equipped with artificial LED light as a sole light source. Each LED light of blue (448 nm), red (634 and 661 nm) or mixed blue plus red (blue:red = 3:7) was separately supplied and the intensity of each light was adjusted to $200{\pm}1{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ at plant level with a photoperiod consisted of 16 hours light and 8 hours darkness. Strawberries grown under mixed LED light of blue and red wavelengths showed a higher production of fruits than those grown under other LED treatments. Fructose, one of the free sugars, increased in mixed LED light-grown fruits. Anthocyanin contents were elevated remarkably in the mixed LED light-grown fruits compared with those in other LED treatments. Contrastingly, contents of total phenolics and flavonoids were not of much different from one another among the fruits treated with various LED lights. On the other hand, ripening of strawberry fruits was found to be faster when grown under blue LED light compared with other LED treatments. Moreover, antioxidant activities of blue or red LED light-grown fruits, respectively, were significantly higher than those of mixed LED light-grown fruits. We suggest that when daylight is in shortage during cultivation in a greenhouse, supplementation of sunlight with LED light, which is composed of blue and red wavelengths, could be useful for the enhancement of productivity as well as of free sugar content in strawberry fruits. In addition, for the strawberry culture in the plant factory, selective adoption of LED light wavelength would be required to accomplish the purpose of controlling fruit maturation time as well as of enhancing contents of sugars and antioxidants of fruits.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.329-333
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• 2003

Fruits of 'Manita', a red pepper cultivar, and 'HL', a cultivar bred for single-harvest, cultivated by direct sowing method were harvested simultaneously. The red fruits were freeze-, sun-, indoor-, hot-air $(65^{\circ}C)$, and excessive hot-air (50% longer time) dried. For Manita. ASTA values of freeze- and indoor-dried red pepper were the highest $(153.6{\sim}168.4)$, and those of sun- and hot air-dried ones were $119.2{\sim}131.5$. Excessive hot-air drying decreased the redness by about $9{\sim}15%$ compared to normal hot-air drying. For HL, ASTA values $(150.3{\sim}171.7)$ of indoor-dried red peppers were much higher than other dried peppers. Red pigment in HL was destroyed easily during sun drying, showing values of only $49.2{\sim}69.2$. By excessive hot-air drying, the redness did not decrease, compared to normal hot-air drying. The organic acid contents of both cultivars were higher in sun- and hot-air-dried ones than freeze- and indoor-dried ones. Copsaicinoid contents of both cultivars decreased up to 22% by excessive hot-air drying compared to normal hot-air drying. Sugar contents were lower in all drying methods other than freeze drying for both cultivars.

• Horticultural Science & Technology
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• v.35 no.4
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• pp.418-430
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• 2017

The objective of this study was to understand the combined effect of shading treatment and harvest time on pungency, ascorbic acid content, market-quality pepper yield, and photosynthetic activity in a yellow 'Star Flame' and 'Fire Flame' F1 hybrid pepper cultivar (Capsicum annuum). Plants were cultivated in a greenhouse under white, red, and green shading nets and compared to those grown under unshaded control conditions. The ascorbic acid and pungency parameters were analyzed by high-performance liquid chromatographic methods. Ascorbic acid, a compound of high nutritive value in pepper, was highest in fruits gathered during the first summer harvest in both hybrids. The ascorbic acid content was found to be further increased in fruits from plants grown under white net shading in both 'Star Flame' and 'Fire Flame'. Total capsaicinoid contents in 'Star Flame' were influenced by the interaction of shading treatment and harvest time (p = 0.004), with the lowest amounts ($241.2-251.5mg{\cdot}kg^{-1}$ fresh weight) resulting from white and red shading treatments at the early autumn harvest. In 'Fire Flame', both shading treatment (p = 0.009) and harvest time (p < 0.001) affected total capsaicinoid contents. We observed significantly higher total capsaicinoid contents in control fruits compared to that resulting from red and green shading treatments at the second harvest, and that resulting from red shading treatment at the third harvest. Analysis of photosynthetic activity revealed a significant and negative correlation between Fv/Fm values and total capsaicinoid contents in both hybrids (p < 0.001). Based on the obtained results, the harvest of peppers during summer should be promoted to produce fruits with high pungency.

• Journal of Nutrition and Health
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• v.9 no.3
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• pp.18-25
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• 1976

To explain the change of the pungent principles of red pepper, capsaicin, during storage, the relation between infecting mold and capsaicin was studied. Results obtained were summarized as follows; 1. Superior strains which showed good growth and high decomposition activity in their culture broths, Aspergillus oryzae and Aspergillus sp. KF-7 were obtained from the contaminated red pepper fruits. 2. The weight of dry matter was increased at low concentration of capsaicin $(2{\sim}3{\mu}g/ml)$ but it was decreased at high concentration. 3. The residual capsaicin in the culture medium was reduced as half as such after 1 week, and almost disappeared after 2 weeks. At $30^{\circ}C$ and $pH\;7{\sim}9$ of culturing condition, the amounts of reducing capsaicin reached to the maximum. 4. At ground red pepper fruits as culture medium, Aspergillus sp. KF-7 could not glow at all, but Aspergillus oryzae showed good growth at 13% of moisture contents and the residual of capsaicin of red pepper fruits after 40days of cultivation time was 45%. 5. At ground red pepper fruits seed as culture medium, Aspergillus oryzae and Aspergillus sp. KF-7 showed good growth, and the residual of capsaicin after 4 weeks of cultivation time was 55% and 38% respectively.

• Horticultural Science & Technology
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• v.30 no.4
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• pp.363-370
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• 2012

Some physicochemical characteristics like nutritional values, sugar content, and fatty acid composition (FAs) in fruits of four papaya (Carica papaya L.) cultivars ('Red Lady', 'Sunrise Solo', 'Tainung', and 'BH-65') grown under plastic greenhouse conditions in the Mediterranean region of Turkey were evaluated. The chemical characteristics, except acidity in the fruits, significantly varied among the cultivars. Nitrogen (N) was the most abundant mineral in all papaya cultivars and ranged from $0.80\;g{\cdot}100\;g^{-1}$ in 'Red Lady' to $1.28\;g{\cdot}100\;g^{-1}$ in 'BH-65' in fresh weight. Potassium (K) and calcium (Ca) were found the highest amount in dry weight. Glucose and fructose were identified as the main sugars in all cultivars. Sucrose was in trace amounts in the three cultivars, but not detectable in cultivar 'Red Lady'. Twenty-five FAs were detected in the papaya fruits. Polyunsaturated fatty acids (PUFAs) were found to be in a highest amounts compared to the saturated fatty acid (SFAs) and monounsaturated fatty acids (MUFAs). Palmitic (C16:0), oleic (C18:1), and linoleic (C18:2n6) acids were the major fatty acids detected in all cultivars. The results of this study implied that dietary intake of papayas may supply substantial nutrient components necessary for human health.

• Research in Plant Disease
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• v.30 no.1
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• pp.13-19
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• 2024

In July 2022 and 2023, black mold symptoms were observed sporadically on fruits of sweet pepper (Capsicum annuum) plants grown in a greenhouse located in Suwon, Korea. The incidence of black mold on the fruits was 5-24% (average 14.8%) in variety SP-504 (yellow and elongate type) and 1-8% (average 5%) in variety SP-505 (red and round type) investigated. Four single-conidium isolates of Alternaria sp. obtained from the diseased fruits were identified as Alternaria alternata based on the morphological characteristics and molecular phyogenetic analyses. The isolates were tested for pathogenicity to sweet pepper fruits of varieties SP-504 and SP-505 through artificial inoculation. The isolates mostly induced large lesions on fruits of the two varieties in the wound inoculation, but only two isolates small lesions on fruits of the variety SP-504 in the non-wound inoculation. No lesions formed on fruits of the variety SP-505 in the non-wound inoculation. The pathogenicity tests revealed that susceptibility of sweet pepper fruits to the disease differs between the varieties. The symptoms induced by pathogenicity tests with the isolates were similar to those observed on fruits from the greenhouse investigated. This is the first report of A. alternata causing black mold on sweet pepper fruits in Korea.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.32-32
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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. The morphological characters were recorded on the field and inside laboratory and 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 USA, RUS, TJK, TKM, TWN, and 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, and microplate reader instrumnets, 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.