• The Korean Journal of Pesticide Science
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• v.21 no.1
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• pp.26-32
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• 2017

Antimicrobial activity of 6 phosphate compounds as $H_3PO_3$, $H_3PO_4$, $K_3PO_4$, $K_2HPO_4$, $KH_2PO_4$ and $NH_4H_2PO_4$ against Phytophthora capsici JHAW 1-2 and Colletotrichum acutatum JC24 was investigated in this study. Inhibitory effect on zoospore release, zoosporangia germination and zoospore germination was superior than mycelial growth. Among 6 compounds, $H_3PO_3$ and $H_3PO_4$ showed the best antimicrobial activity against P. capsici JHAW 1-2. Diseases controlling activity of the phosphate compounds tested on seedling and fruit of pepper against Phytophthora blight was also better than those against anthracnose. When $H_3PO_3$ was applied to the pepper seedlings at a concentration of $100{\mu}g\;mL^{-1}$, severe phytotoxicity was occurred. However, with applying $10{\mu}g\;mL^{-1}$ of $H_3PO_3$ showed 100% the disease control efficacy. In case of $100{\mu}g\;mL^{-1}$ $H_3PO_4$ application showed excellent antimicrobial activity against P. capsici JHAW 1-2, and 56.7% of the disease control efficacy with no phytotoxicity. To investigate the control efficacy against anthracnose, conidia suspension was inoculated with non-wound and wound inoculation method on pepper fruit. Among 6 compounds, only $100{\mu}g\;mL^{-1}$ of $H_3PO_3$ and $H_3PO_4$ had a activity of more than 70%, but the control activity on other treatments was minimal or unacceptable.

• Research in Plant Disease
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• v.29 no.4
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• pp.345-362
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• 2023

Anthracnose, caused by the Colletotrichum genus, comprises a significant number of plant pathogens and poses a major threat to fruit production worldwide, including South Korea. Colletotrichum species were identified associated with anthracnose in fruits such as apple, persimmon, plum, peach, jujube, walnut, and grape. A polyphasic approach, including morphology, multigene phylogenetics, and pathogenicity testing, was used. Additionally, the in-vitro sensitivity of identified Colletotrichum species to common fungicides was also evaluated. A total of nine Colletotrichum species within two complexes, namely gloeosporioides and acutatum, have been identified as the causal agents of anthracnose in common fruits in South Korea. In the gloeosporioides complex, we found Colletotrichumaenigma, C. fructicola, C. gloeosporioides, C. horii, C. siamense, and C. viniferum. Meanwhile, in the acutatum complex, C. fioriniae, C. nymphaeae, and C. orientalis were identified. Notably, C. fructicola, C. siamense, C. fioriniae, and C. nymphaeae were reported for the first time from apple, C. siamense, C. fioriniae and C. nymphaeae from plum, C. siamense, C. fructicola, and C. fioriniae frompeach, C. siamense and C. horii from persimmon, C. fioriniae from Omija (Schisandra), C. orientalis from walnut, C. nymphaeae from jujube, and C. aenigma, C. fructicola, and C. siamense fromgrape. Fungicide sensitivity tests revealed significant variation in the EC₅₀ values among specific Colletotrichum species when exposed to different fungicides. Moreover, the same Colletotrichum species isolated from different host plants displayed varying sensitivity to the same fungicide.

• Horticultural Science & Technology
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• v.34 no.3
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• pp.355-362
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• 2016

This study was carried out to investigate the effects of rain-shelter types on growth, and fruit quality of red pepper (Capsicum annuum, 'Kemmaru') cultured in paddy. Applied rain-shelter types were outfield (control), simple rain-shelter plastic house with 2 rows (2R), simple rain-shelter plastic house with 4 rows (4R), and perfect plastic house (House). The plant height was the highest in Houses treatment. There was no difference in leaf length and width among the rain-shelter treatments. The fresh and dry weight of red pepper was high in order of House > 4R > 2R > Control. The ASTA value is irregular tendency among the treatments. Hunter's color value 'a' and 'b' was not different from among the treatments. Phytophthora blight, powdery mildew, bacterial spot were not occurred in all of treatments, and Anthracnose was only occurred in control. Mite, Microcephalothrips abdominalis, and Bemisia tabaci were not occurred in all of treatments, and aphid, Helicoverpa assulta, and virus were occurred all of treatments as same degree. Our results will provide rain-shelter cultivation of red pepper can be increase dry yield and decrease disease and insects.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.515-518
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• 2010

'Gangha' is new strawberry ($Fragaria{\times}ananassa$ Duch.) cultivar, which was released by National Institute of Highland Agriculture, RDA, in 2008. In 2004, this cultivar was originated from a cross between 'Samahberi' and 'Elan' and showed excellent ever-bearing characteristics including continuous flowering habit, high yield under long-day and high temperature condition. It was named 'Saebong No.2' after examining its characteristic and productivity in summer culture from 2006 to 2007. Again, after two regional adaptability tests in 2008, 'Gangha' was selected as an elite cultivar. The general characteristics of 'Gangha' include semi-spreading type, middle vigor, elliptic leaf, and long cluster in growth. The fruit shape is oval and fruit color is red. Fruit quality had 1ow activity, hardness but high soluble solids contents. This average fruit weight of 'Gangha' is about 12.0 g and the marketable yield is relatively high because of more flower cluster appearance. It is resistant against powdery mildew, anthracnose, and fusarium wilt. 'Gangha' is suitable for summer culture using domestic consumption because it is shows continuous flowering habit, high yield, and fruit quality under long-day and high temperature condition.

• Horticultural Science & Technology
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• v.33 no.3
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• pp.443-447
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• 2015

Fragaria ${\times}$ ananassa (Duch.) cultivars, 'Wongyo 3 115' a nd 'Wongyo 3 116', we re bre d as a n inte rme diate parent l ine using heterosis of $F_1$ hybrids in octoploid strawberry. These two new cultivars were developed as inbred lines ($S_9$ generation) propagated from both seed and runners/stolons. 'Wongyo 3115', an inbred line derived from the 'Benihoppe' cultivar, has a semi-upright plant shape showing a vigorless growth habit, weaker than the original 'Benihoppe' cultivar; it has early flower bud differentiation and produces 10 flowers per cluster when grown from healthy seed. 'Wongyo 3115' has low yields of conical type fruit with pink colored skin; average fruit weight is approximately 11 g. The important characteristic of 'Wongyo 3115' is its excellent fruit firmness, firmer than the original variety. 'Wongyo 3116', an inbred line derived from the 'Doyonoka' cultivar, has an upright plant shape, vigorless growth habit, weaker than that of the original 'Doyonoka' cultivar; it has early flower bud differentiation and produces 8 flowers per cluster when grown from healthy seed. 'Wongyo 3 116' has oblate type fruits with red skin and an ave rage weight of approximately 12 g. The important characteristics of 'Wongyo 3116' are excellent fruit shape and higher yield than other inbred lines, although it produces small fruits compared to the original cultivar. Both cultivars have excellent taste, high sugar/acid ratio, and good texture. In regards to disease and pest resistance, 'Wongyo 3115' and 'Wongyo 3116' have a tendency to be sensitive to powdery mildew, anthracnose and the two-spotted spider mite.

• The Plant Pathology Journal
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• v.25 no.3
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• pp.205-212
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• 2009

Colletotrichum acutatum was the main cause of the recent outbreaks of anthracnose on pepper fruit in Korea. To facilitate molecular analysis of C. acutatum, we generated an arginine auxotrophic mutant of the C acutatum strain JC24 using a targeted gene replacement strategy. A 3.3-kb genomic region carrying an ortholog (designated CaARG2) of the fungal gene encoding N-acetylglutamate synthase, the first enzyme of arginine biosynthesis in fungi, was deleted from the fungal genome. The mutant exhibited normal growth only when arginine was exogenously supplied into the culture medium. Transformation of the arginine auxotrophic mutant with a plasmid DNA carrying an intact copy of CaARG2, which was smaller than the deleted region in the mutant, not only caused random vector insertions in the fungal genome, but also recovered both hyphal growth and pathogenicity of the mutant to the wild-type level. Using this new selection system, we have successfully developed a restriction enzyme-mediated integration procedure, which would provide an economically efficient random mutagenesis method in C. acutatum.

• Proceedings of the KAIS Fall Conference
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• 2011.05b
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• pp.924-925
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• 2011

수박 '스피드'에서 칼슘제를 착과 14일 후에 1회 엽면 살포한 후 식물체의 칼슘농도, 과실품질 및 탄저병 발생을 조사하였다. 식물체 부위별 칼슘농도는 엽병에서 ECa 500배 처리구는 다른 처리구보다 현저하게 높았으며 과피에서는 MCa 500배 및 염화칼슘 0.4%에서 현저하게 높았다. 과육에서는 무처리에 비하여 ECa, MCa 및 염화칼슘 모두 높았다. ECa 칼슘제 희석배수에 의한 엽병의 칼슘 농도는 500배, 250배, 125배에서 높았다. 수확 시 과중은 무처리 및 염화칼슘 0.4%에 비하여 ECa 및 MCa 처리에서 유의하게 증가하였다. 당도 및 과피두께 차이는 없었다. 탄저병 발생은 무처리에 비하여 처리 칼슘제 모두 낮았다. 생리장해과 발생은 육안으로 전처리 모두 관찰할 수 없었다.

• Korean Journal Plant Pathology
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• v.3 no.2
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• pp.85-92
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• 1987

The present researches were carried out to differentiate the species of Colletotrichum by elecrophoretic method. C. gloeosporioides, C. dematium and Gloeosporium fructigenum could be differentiated by the isozyme patterns of esterase, leucine aminopeptidase, acid phosphatase and glutamic oxaloacetic transaminase. Especially. G-strain and R-strain of C. gloeosporioides were differentiated by the enzyme patterns. The G­strain damaged all stage fruits (green and red fruits) of Capsicum annum. The R-strain could not infect the unripe (green) fruits, but it could damage only ripe (red) fruit of Capsicum annum.

• Korean Journal of Medicinal Crop Science
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• v.7 no.3
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• pp.147-154
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• 1999

This research was carried out to obtain the field resistance to disease and pest, and high yielding of new Boxthorn (Lycium chinense Mill.) varieties. Growth characteristics, yield potential, correlation of trait which was related the yield and path coefficient of the domestic native varieties. two of cultivated varieties and four of introduced varieties were investigated. In growth characters of collected varieties, the stem length of collected varieties in China were slightly long. Leaf area in Jindo, Kumsan native and Yusong 1 and 2 were wider than that of other varieties. Resistance to pest iniury was very strong at China 1, Japan 1 and Yusong 2 in eriophyidmite, and also resistance to anthrax anthracnose were showed less than 10% of the rate of attack fruit at Japan 1 and China 1. Flowering stage was more early in Chungyang native than that of other varieties. Fruit size of Kumsan native, Yusong 2 were large size fruit varieties. Fruit setting number was most abundant at 1,623 in Yusong 2 which was collected variety. And dry yields of fruit per lOa was more cmparatively abundant in Yusong 2 at 86% than those of Chungyang native. The high correlation cofficienct character with fruit yield were fruit setting and branching number and leaf area. Direct effect by path anaslysis were fruit setting number (Py=0.45), and branching number was showed indirect effect.

• Horticultural Science & Technology
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• v.30 no.6
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• pp.780-783
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• 2012

A new strawberry cultivar (Fragaria ${\times}$ ananassa Duch.) 'Okmae' was developed from a cross between 'Toyonoka' and 'Maehyang'. This cultivar has a good fruit quality and suitable number of flowers per cluster for labor saving in fruit thinning. 'Gyoengnam No. 1' was selected as an elite line with vigorous plant growth, higher soluble solids content and fruit firmness after examining its characteristics and productivity in forcing cultures from 2007 to 2009. Farmer's field trial of 'Gyoengnam No. 1' was conducted in 2010 and it was registered as 'Okmae' thereafter. The general characteristics of 'Okmae' are vigorous growth habit, erect plant type, less number of leaf and elliptic leaf shape. 'Okmae' has long peduncle and 9-10 flowers per flower cluster which need less labor for fruit thinning. Fruits of 'Okmae' are conical having a bright red and glossy skin color. Although 'Okmae' has a smaller average fruit number per plant of 21.9 than that of the control cultivars, it's possible to produce high yield because of greater fruit weight of 26.0 g. 'Okmae' showed a high soluble solids content of $11.6^{\circ}Brix$, low acidity of 0.37%, and high firmness of $14.5g{\cdot}mm^{-2}$. It is sensitive to anthracnose and powery mildews, but high-quality strawberry can be harvested by using effective control measure.