• Korean Journal Plant Pathology
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• v.14 no.1
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• pp.99-101
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• 1998

A severe brown rot on peach fruit caused by a Phytophthora sp. has occurred at peach orchards in Taegu of Korea from late June to early August in 1997. Infected fruits showed irregularly round or circular water soaking brown regions. In the severe case, fruits were entirely rotten and surface of the fruits were wrinkled. Occasionally, white mycelia and abundant sporangia were developed on the surface of fruit. Inner tissues of the fruits were also discolored to brown. The causal fungus was identified as Phytophthora cactorum based on following characteristics. Sporangia were ovoid, conspicuously papillate, caducous and measured as 28.4~48.1$\times$21.9~37.2 (av. 39.9$\times$30.4) ${\mu}{\textrm}{m}$. Sexuality of the fungus was homothallic. Oogonia were 25.0~34.0 (av. 29.9) ${\mu}{\textrm}{m}$ in size. Most antheridia were paragynous and measured av. 10.5$\times$13.0 ${\mu}{\textrm}{m}$. Optimum temperature for mycelia growth was around 25~3$0^{\circ}C$. However none of the isolates grew under 7$^{\circ}C$ and over 35$^{\circ}C$. The fungus revealed high pathogenicity to fruits, shoots and leaves of peach, apple and pear with different degrees. Phytophthora fruit rot of peach caused by Phytophthora cactorum has not been reported in Korea previously.

• Mycobiology
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• v.31 no.4
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• pp.205-208
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• 2003

The production of polysaccharide according to various developmental stages(mycelium growth, primordium appearance, and fruiting-body formation) in the edible mushroom Grifola frondosa was studied. The cap of the mature mushroom showed the highest amount of polysacchride. Mycelial growth and polysaccharide synthesis were optimal at pH 5 and $20^{\circ}C$. Polysaccharide synthesis was maximal after 12 days of cultivation, whereas maximum mycelial growth was shown after 18 days. Mannose, cellobiose and starch increased the level of polysaccharide as well as growth in submerged culture. Glucose and sucrose appeared to be good substrates for fruiting of Grifola frondosa.

• The Plant Pathology Journal
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• v.33 no.6
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• pp.572-581
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• 2017

Anthracnose of papaya fruit caused by the fungus Colletotrichum gloeosporioides is one of the most economically important postharvest diseases. Hot water immersion (HW) and calcium chloride (Ca) treatments have been used to control papaya postharvest diseases; however, the effect of the combination HW-Ca on the pathogen growth and the development of the disease in infected papaya fruit has been scarcely studied. The aim of this study was to evaluate the effect of the HW-Ca treatment on the in vitro growth of C. gloesporioides conidia and the quality of infected papaya. In vitro, the HW-Ca treated conidia showed reduced mycelial growth and germination. In vivo, the HW-Ca treatment of infected papaya delayed for 5 days the onset of the anthracnose symptoms and improved the papaya postharvest quality. The combined treatment HW-Ca was better than any of the individual treatments to inhibit the in vitro development of C. gloeosporioides and to reduce the negative effects of papaya anthracnose.

• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.167-173
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• 2007

This study was conducted to improve light environment of oriental melon cultivation in winter season. Three polyolefin foreign films (J-1, J-2, J-3) and three polyethylene domestic films (K-1, K-2, K-3) with different film thickness, ultraviolet ray interception and infrared ray absorption were used. As the result of this experiment, soluble solid of oriental melon fruit in K-3 was $14.3^{\circ}Brix$, those in J-3 and J-2 were higher by 1.3 and $0.8^{\circ}Brix$, respectively. Chromaticity (a value) of pericarp in K-3 was 0.5, those in J-3, J-1 and J-2 were higher by 3.3, 2.3 and 1.9, respectively. Especially, fermented and malformed fruit rates in J-1, J-2 and J-3 were decreased and marketable fruit rates were increased. Marketable yield in K-3 was 1,622 kg per 10a, those in J-1, J-3 and J-2 were increased by 31.2%, 23.8% and 18.5% compare to K-3, respectively. In this study, Polyolefin films (J-1, J-2, J-3) with thickness and infrared ray absorption ratio keeping higher heat conservation, therefore, soluble solid and chromaticity of fruit were increased, fermented fruit rate was decreased, and marketable fruit rate and yield were increased.

• Journal of Bio-Environment Control
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• v.11 no.4
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• pp.181-187
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• 2002

The overall objective of this study was to improve tomato fruit quality, while maximizing yield. The variety of 'Momotaro' was grown in the basic nutrient solution of 1.6 dS.m$^{[-10]}$ which was supplemented by three levels of seawater with EC 1.0, 2.0 or 3.0 dS.m$^{[-10]}$ . Tomato plants were cultivated in cool seasons. Plant growth characteristics were compared between treatments, and fruits were classified to analyse fruit quality characteristics according to ripening stages： MG, Br, Br＋3, Br＋5, Br＋7 and Br＋10. Adding seawater generally did not affect the shoot growth parameters such as plant height, leaf length, leaf width, internode length and chlorophyll content. Adding seawater negatively affected yield parameters such as the height and weight of fruit, marketable fruit weight per plant and marketable fruit yield. Therefore, the more yield reduction was obtained with the increasing level of seawater treatment. Fruit quality was improved by seawater treatment. The degree of the effect for $^{\circ}$Bx degree and sugars were the highest with the EC of seawater 2.0~3.0 dS.m$^{[-10]}$ , and at the Br＋5~Br＋7 of ripening stages. The relative abundance of tomato flavor, volatile components, was not generally affected by the seawater treatment with an exception of 6-methyl-5-hepten-2-one. The relative abundance of most volatile components increased as ripening progressed. The increment began at the Br stage and showed the highest increment at the Br＋5~Br＋7 stages. The results from these experiments suggest that seawater treatment of EC 3.6 dS.m$^{[-10]}$ for hydroponics is good for improving tomato quality. Fruit quality is the best at the Br＋5~Br＋7 ripening stages. It is considered that these results may be applied far use in hydroponic culture to improve fruit quality with minimum yield reduction.

• Food Science of Animal Resources
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• v.26 no.1
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• pp.144-147
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• 2006

This experiment was carried out to investigate the effect of mulberry fruit extinct on the acid production and growth of lactic acid bacteria. The extract of mulberry fruit was showed a high level of yield with 60% ethanol extraction. Lactic acid bacteria was used in a starter culture of Lactobacillus casei YIT9018 and 2782, and Lactobacillus acidophilus NCFM. After 24 hr culture in MRS broth added with 1.0, 5.0 and 10% of the extract 1.0% addition of the extract was showed pH $4.04{\sim}4.19$, titratable acidity $1.25{\sim}1.42%,\;and\;1.2{\sim}7.8{\times}10^9\;cfu/mL$ of viable cell count. The additions above 1.0% extract (5.0% and 10.0% addition) showed slightly lower effect than 1.0% addition. However, the addition of the extract showed a high effect on the growth of lactic acid bacteria comparing with the control. In yoghurt preparation with the extract, 1% addition of the extract showed a high effect on the growth of lactic acid bacteria, Therefore, it was suggested to manufacture of the yoghurt with the addition of 1% mulberry fruit extract and the inoculation of culture of Lactobacillus acidophilus for on the stimulation of growth of the lactic culture.

• Journal of Ginseng Research
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• v.45 no.4
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• pp.527-534
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• 2021

Background: Phenological studies are a prerequisite for accomplishing higher productivity and better crop quality in cultivated plants. However, there are no phenological studies on Panax ginseng that improve its production yield. This study aims to redefine the phenological growth stages of P. ginseng based on the existing Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie (BBCH) scale and proposes a disease control reference. Methods: This study was conducted at the Korea Ginseng Corporation Experiment Station in Gyeonggi province, South Korea. Phenological observations were performed once weekly or twice monthly, based on the developmental stages. The existing BBCH scale with a three-digit code was used to redefine and update P. ginseng's phenological growth codes. Results: The phenological description is divided into eight principal growth stages: three for vegetative growth (perennating bud, aerial shoot, and root development), four for reproductive growth (reproductive organ development, flowering, fruit development, and fruit maturation), and one for senescence according to the extended BBCH scale. A total of 58 secondary growth stages were described within the eight principal growth stages. Under each secondary growth stage, four mesostages are also taken into account, which contains the distinct patterns of the phenological characteristics in ginseng varieties and the process of transplanting seedlings. A practical management program for disease control was also proposed by using the BBCH code and the phenological data proposed in this work. Conclusion: The study introduces an extended BBCH scale for the phenological research of P. ginseng.

• Horticultural Science & Technology
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• v.29 no.6
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• pp.555-560
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• 2011

The objective of this study was carried out to investigate the proper plant growth regulator for increasing the number of flower, fruit set, and to enlarge the size of the berries in Ardisia pusilla. Flower bud formation was used rooted cutting, and fruit set, enlargement, and coloration of fruit were used with two years-old. $GA_3$ concentrations were treated with 0, 100, 200, or $400mg{\cdot}L^{-1}$. Flower bud formation was effective in $400mg{\cdot}L^{-1}$ $GA_3$ and it was 1.8 times greater than control. Plant growth regulators were applied by foliar spray at full bloom stage to increase the fruit set. As a result, $GA_3$ was the most effective for increasing fruit set. Also, auxins of 4-CPA (Tomatotone, Donbu hitech Co., Korea) and dichloprop triethanol amine (Antifall, Bayer Crop Science Co., Ltd., Korea) were effective. When $GA_3$ concentrations of 0.5 and $1.0mg{\cdot}L^{-1}$ were used, fruit set (%) reached to 70% and 77%, respectively. Effectiveness of $GA_3$ was 1.8 times greater than control. Also, auxins, dichloprop triethanol amine increased to about 7-12% during fruit setting, but cytokinin and anti-gibberellin were ineffective. To investigate the fruit enlargement and coloration, $GA_3$ was treated with 0.3, 0.6, and $1.2mg{\cdot}L^{-1}$. Fruit enlargement was achieved to about 15% by $GA_3$ $0.6mg{\cdot}L^{-1}$ when $GA_3$ was treated 3 times at the interval of 1 month per treatment when fruit size was about 2-3mm (after full-blooming two months). But anthocyanin contents for coloration of fruit skin were not significant according to $GA_3$ concentration. The results showed that $GA_3$ enhanced bud formation, fruit set and enlargement of fruit size in Ardisia pusilla.

• 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.

• Mycobiology
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• v.37 no.2
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• pp.77-81
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• 2009

This study was conducted to identify the Colletotrichum species causing anthracnose disease of strawberry in Balgladesh and to evaluate in vitro activity of commercial fungicides it. Based on morphological and cultural characteristics, all 22 isolates were identified as Colletotrichum gloeosporioides. They developed white or glittery colonies with grey to dark grey reverse colony colors and they produced cylindrical conidia. The efficacy of five commercial fungicides, Bavistin DF, Dithane M-45, Sulcox 50 WP, Corzim 50 WP and Rovral 50 WP, were tested against the fungus. Bavistin inhibited radial growth completely and was followed in efficacy by Dithane M-45. In Bavistin DF treated media, the fungus did not produce conidia. The percent inhibition of radial growth of the fungus was increased with the increasing concentrations of fungicide.