• 한국식물병리학회지
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• 제14권2호
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• pp.109-114
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• 1998

To investigate Phomopsis species causing fruit decays of Japanese apricot, apple and kiwifruit, we collected diseased fruits from the fruit markets in 1995 and 1996 respectively. Phomopsis mali Roberts was identified based on cultural characteristics, morphological aspects and pathogenicity. There were no remarkable differences with respect to $\alpha$ and $\beta$ conidia, growth rates and colony characters among the isolates from Japanese apricot, apple and kiwifruit. The pathogens grew more than 70 mm on potato dextrose agar in 5 days at $25^{\circ}C$. The agar was slightly discolored by the production of a reddish purple pigment under the light at $25^{\circ}C$ and 3$0^{\circ}C$ respectively. Only $\alpha$ spores of the different isolates of P. mali were formed at 15$^{\circ}C$ and $\beta$ spores were mainly produced at 3$0^{\circ}C$, but and $\alpha$ and $\beta$ spores were produced in approximately equal numbers at 2$0^{\circ}C$ and $25^{\circ}C$. Pycnidia were a few under the dark condition but were abundant at wide range of 15~3$0^{\circ}C$ under near ultra violet illumination. Conidia were two types : $\alpha$ spores were unicellar, fusoid, hyaline and biguttulate, whereas $\beta$ sores were unicellar, acicular to filiform, straight or hooked and hyaline. An ascigerous stage was not formed in cultures or in nature. Isolates of Phomopsis mali from japanese apricot, apple and kiwifruit could infect fruits of apple, pear, apricot, Japanese apricot and kiwifruit. There were some differences in pathogenicity depending on stocks of fruit crops tested.

• The Plant Pathology Journal
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• 제38권3호
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• pp.220-228
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• 2022

Pollen is a vector for viral transmission. Pollenmediated viruses cause serious economic losses in the fruit industry. Despite the commercial importance of pollen-associated viruses, the diversity of such viruses is yet to be fully explored. In this study, we performed metatranscriptomic analyses using RNA sequencing to investigate the viral diversity in imported apple and kiwifruit pollen. We identified 665 virus-associated contigs, which corresponded to four different virus species. We identified one virus, the apple stem grooving virus, from pear pollen and three viruses, including citrus leaf blotch virus, cucumber mosaic virus, and lychnis mottle virus in kiwifruit pollen. The assembled viral genome sequences were analyzed to determine phylogenetic relationships. These findings will expand our knowledge of the virosphere in fruit pollen and lead to appropriate management of international pollen trade. However, the pathogenic mechanisms of pollen-associated viruses in fruit trees should be further investigated.

• 식물병연구
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• 제21권2호
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• pp.67-73
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• 2015

P. syringae pv. syringae에 의해 발생하는 참다래 꽃썩음병은 개화기 전후의 기상조건에 영향을 크게 받는다. 지금까지 기상조건과 꽃썩음병 발생의 상관관계를 밝힌 연구들은 많았지만, 이를 활용해 꽃썩음병의 감염 위험도를 나타낼 수 있는 예측모형은 개발되지 않았다. 본 연구에서는 기존 정보를 조사하고 꽃썩음병의 병원생태와 유사한 화상병 예측모형인 Maryblyt모형을 기반으로 참다래 꽃썩음병 예측모형인 Pss-KBB Risk Model을 개발하였다. 비교평가를 통한 검증 결과, Pss-KBB Risk Model은 각각 온도와 강수 정보만을 이용하는 개화전 평균온도 모형과 강우일수 모형에 비해 실제 과수원의 병해 발생정도를 더 잘 모의하는 것으로 나타났다. 따라서 Pss-KBB Risk Model과 기상예보자료를 활용해 꽃썩음병의 발병 위험도를 예측하여 꽃썩음병에 대한 적기적량 방제가 가능할 것으로 판단된다.

• The Plant Pathology Journal
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• 제19권5호
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• pp.227-230
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• 2003

Ripe rot was commonly found in overripe kiwifruits (Actinidia deliciosa) during a disease survey conducted in Jeju and Jeonnam provinces in Korea in 1999. While the disease did not manifest any clear external symptoms on kiwifruits, it caused portion of the fruit surface to collapse. Watersoaked flesh tissue could be seen on the sunken part when the skin of the collapsed portion was peeled off. The milky internal symptom with dark green margin developed concentrically as the fruit ripened. A species of Botryosphaeria was consistently isolated from lesions showing typical symptoms of ripe rot on kiwifruit, and its pathogenicity was confirmed by artificial inoculation test on healthy kiwifruits. The fungus was also pathogenic to apple and pear. The mycological characteristics of the fungus were consistent with those of Botryosphaeria dothidea. This is the first report on the detailed mycological characteristics of the causal organism of post-harvest ripe rot of kiwifruit in Korea.

• 한국식물병리학회지
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• 제13권1호
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• pp.22-29
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• 1997

Etiological and ecopathological studi88888es on the leaf blight of kiwifruit (Chinese gooseberry), a disease newly found in 1993 in Korea, were carried out in this experiment. The leaf blight symptom was prevalent in the southern area of Chonnam Province where kiwifruits were widely cultivated. The disease occurred from July to fall, causing early defoliation of kiwifruit vines. Small brownish circular or irregular lesions appeared initially on the leaves, starting from the marginal leaf areas, and enlarged. Afterwards small grayish black granules (acervuli) were formed on the lesions. The color of old lesions changed to grayish brown or grayish white. The causal fungus was identified as Pestalotiopsis menezesiana (Bress. & Torr.) Bissett according to its morphological characters and pathogenicity (pathogenic to Chinese gooseberry and grapevine, but not to other hosts of Pestalotiopsis spp.such as tea, apple, persimmon, and chestnut). As P. longiseta and P. neglecta were reported recently in Japan as pathogens causing similar blight symptoms in kiwifruit, P. menezesiana is a new leaf blight pathogen in kiwifruit. Development of the disease was stimulated by wounding, prevailing wind, and drought. The causal fungus was proven to be overwintered in the diseased leaves on the ground surface.

• 원예과학기술지
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• 제35권1호
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• pp.142-146
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• 2017

In Korea, kiwifruit is grown within a limited region on the southern coast where the climate is warm. Since the yellow - fleshed kiwifruit variety, 'Hort16A', first became commercially available, we have focused on breeding additional yellow - fleshed kiwifruits. Here, we describe the cultivar 'Goldone', which originated from 'Red Princess' and is characterized by red coloration around the fruit core. Conventional field crosses were performed in 2003, and permission for final release of 'Goldone' was obtained in 2011. This cultivar is very productive, with an average fruit weight of 129 g, which is 39% heavier than that of the cultivar 'Hayward'. 'Goldone' is harvested in late October, approximately 165 - 170 days after anthesis. In general, 'Goldone' has approximately eight flowers per fruiting shoot; these flowers must be thinned before blooming for commercial production. 'Goldone' was registered at the Korean Seed & Variety Service in 2014 for plant variety protection rights (grant no. 4835).

• 한국육종학회지
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• 제40권4호
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• pp.461-465
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• 2008

"그린킹"은 제주특별자치도에 위치한 농촌진흥청 난지농업연구소에서 2005년에 육성한 껍질째 먹을 수 있는 다래품종이다. 이 품종은 Actinidia chinensis cv. "Apple Sensation"을 모본으로 하고 A. arguta를 부본으로 하여 1998년에 교배를 실시하였다. 실생육성과 계통선발은 1999년에서 2002년까지 실시하고 2003년에서 2004년까지 특성검정을 실시하였다. 수세는 야생다래와 비슷하게 강한 편이었으며 잎은 약간 암녹색을 나타내었다. 과실의 형태는 원통형이었고 과피는 녹색 또는 황녹색을 나타내었으며 털이 없다. 평균과중은 15.9g이고 과심은 작고 부드럽다. 과육색은 밝은 녹색이고, 당도는 $15.4^{\circ}Brix$를 나타내었으며 산도는 로 1.3%로 약간 신맛이 있다. 생산량은 야생다래 보다 약 2배 정도 높으며 수확기는 10월 중순이다. 이 품종은 우리나라 중남부지방에 재배가 가능할 것으로 판단된다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1128-1128
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• 2001

We have developed a probe for measuring the light levels inside illuminated fruit. The probe has minimal effect on the light levels being measured and enables the sampling of the light flux at any point within the fruit. We present experimental light extinction rates within apple, nashi, kiwifruit, and mandarin fruit. Moving from the illuminated side to the far side of the fruit, the extinction level follows an initial power law decay as the light diffuses into the fruit then reduces to an exponential decay through the rest of the fruit. Significant variations in the rates of light extinction are found in the core, skin and differing flesh regions. Monte Carlo simulations of the light distribution in fruit, which use scattering and absorption coefficients for the diffusely scattering tissue, and boundary conditions for the skin effects, produce results that follow the experimental results closely.

• The Plant Pathology Journal
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• 제37권3호
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• pp.299-306
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• 2021

Pollination is an essential process for plants to carry on their generation. Pollination is carried out in various ways depending on the type of plant species. Among them, pollination by insect pollinator accounts for the most common. However, these pollinators have be decreasing in population density due to environmental factors. Therefore, use of artificial pollination is increasing. However, there is a lack of information on microorganisms present in the artificial pollens. We showed the composition of bacteria structure present in the artificial pollens of apple, kiwifruit, peach and pear, and contamination of high-risk pathogens was investigated. Acidovorax spp., Pantoea spp., Erwinia spp., Pseudomonas spp., and Xanthomonas spp., which are classified as potential high-risk pathogens, have been identified in imported pollens. This study presented the pollen-associated bacterial community structure, and the results are expected to be foundation for strengthening biosecurity in orchard industry.

• 원예과학기술지
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• 제35권3호
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• pp.387-391
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• 2017

Kiwifruits introduced to Korea typically have green fruit flesh, yellow flesh, or yellow flesh with red coloration around the core. Here, we describe a new cultivar called 'Redvita', the first kiwifruit cultivar of Korea with yellow flesh and red coloration around the core. A conventional field cross was conducted in 2003, and permission for the final release of 'Redvita' was obtained in 2012. 'Redvita' originates from 'Red Princess', a maternal vine known for the red coloration in its flesh. The pollinizer is 'NHK0013' (IT233175), which blooms in early May. A principal feature of 'Redvita' is its high vitamin C content, which at an average of 140 mg per 100 g of fresh weight is 2 - 4 times higher than other commercial cultivars. The average fruit weight is 97 g; bigger than that of the control cultivar 'Hongyang'. 'Redvita' blooms in mid-May and is usually harvested in early to mid-October, approximately 150 - 160 days after anthesis. 'Redvita' produces 3 or 4 flowers per fruiting shoot, with no small lateral flowers, therefore does not need to be thinned before blooming for commercial production. The cultivar is acidulous because of a high titratable acidity content (about 1.5%), which is higher than other cultivars (less than 1.0%). 'Redvita' was registered with the Korean Seed and Variety Service in 2015 for plant variety protection rights (no. 5604).