• Research in Plant Disease
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• v.10 no.3
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• pp.183-187
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• 2004

Black spot disease on sweet persimmon (Diospyros kaki cv. Fuyu) was found from the farmer's refregerated ware house located in Dong-eup, Changwon city, Gyeongnam province, Korea, 2002. The typical symptoms of the disease was appeared black spot on surface of fruits. Colonies of causal fungus were developed velvety and later turned olivaceous black to sooty black in color on PDA. Conidia were pale brown to golden brown in color and ovoid, obclavate to obpyriform, rarely ellipsoid in shape. and were 12∼46 ${\times}$ 6∼12 ${\mu}{\textrm}{m}$ in size. Septa were 3∼5 transvers, 1∼2 longitudinal or oblique. Conidia were mostly beakless and generated chains by means of secondary conidiophores. Conidiophores were pale to mid brown in color and 42∼95 ${\times}$ 3∼5 ${\mu}{\textrm}{m}$ in size. The optimum temperature for growth of the fungus was about 25∼3$0^{\circ}C$. This is the first report on the black spot of sweet persimmon caused by Alternaria alternata (Fr.) Keissler in Korea.

• Research in Plant Disease
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• v.14 no.1
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• pp.61-63
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• 2008

Anthracnose of blueberry (Vaccinium spp.) caused by Colletotrichum gloeosporioides was observed in the exhibition orchard of Gyeongsangnam-do Agricultural Research and Extension Services in Korea, 2007. The typical symptoms were initially water-soaked lesions and then rotten on fruits, the infected fruits were dropped but some of them were hunged and mummified. The pathogenic fungus grown on potato dextrose agar showed greyish to dark gray color. Conidia were straight, cylindrical apex obtuse in shape and $10{\sim}20{\times}3{\sim}5\;{\mu}m$ in size. Appressoria were brown in color, clavate or ovate in shape and $6{\sim}18{\times}4{\sim}12\;{\mu}m$ in size. Optimum temperature for mycelial growth was $25{\sim}30^{\circ}C$. On the basis of mycological characteristics and pathogenicity test on host plants, the fungus was identified as Colletotrichum gloeosporioides (Penz.) Penz. & Sacc.. This is the first report on the anthracnose of blueberry (Vaccinium spp.) caused by C. gloeosporioides in Korea.

• Journal of Korean Society of Forest Science
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• v.103 no.3
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• pp.353-358
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• 2014

In order to obtain the basic data that could be used to evaluate the harvest time of new hardy kiwifruit cultivars (Actinidia arguta 'Saehan', 'Daesung' and 'Chilbo'), the seasonal fruit quality and ripening characteristics of hardy kiwifruit were investigated. Fruit sizes of 'Saehan', 'Daesung' and 'Chilbo' were increased from full bloom to 66 days, 85 days and 78 days, respectively. The growth curve of developing fruit of three cultivars showed double sigmoid. As a result of correlation analysis, the seed number per fruit showed a significant positive correlation with fruit weight (r = 0.94~0.97, p<0.01). Fruit length, width, thickness, weight, soluble solid content and titratable acidity were significantly different among the cultivars. Titratable acidity was increased from full bloom to harvest time and the titratable acidity of 'Saehan', 'Daesung' and 'Chilbo' were 1.77%, 1.22% and 1.37% on havest time, respectively. Optimal harvest time of 'Saehan' was 108 days (23 Sep.) after full bloom, those of 'Daesung' and 'Chilbo' were 92 (9 Sep.) days after full bloom.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.392-396
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• 2010

This research focused on determining the effectiveness of cluster and/or flower thinning in highbush 'Jersey' blueberry on the yield and fruit quality. The total yield and quality of fruit were compared between thinning methods of control (no thinning), 1/3 cluster thinning, 1/3 cluster thinning + 1/2 flower thinning, 2/3 cluster thinning, and 2/3 cluster thinning + 1/2 flower thinning per each bearing shoot, respectively. Thinning strength significantly affected the yield of bearing shoot and, thus, total yield of control and 1/3 cluster thinning was higher than others. Both cluster and flower thinning, however, significantly affected the fruit growth resulting in the increase of fruit weight, length and width. Even total yield was similar between control and 1/3 cluster thinning, more larger fruit (> 1.6 g) were produced by 1/3 cluster thinning treatment, indicating that flower and/or cluster thinning contributed to the increase of individual fruit growth. Unlike fruit growth, fruit quality was less affected except total soluble solid contents. Total soluble solid level significantly increased in treatments (2/3 cluster thinning, 2/3 cluster thinning + 1/2 flower thinning) with yield decrease. No significant difference in levels of acidity and firmness of fruit was found. Results indicated that fruit growth and total yield of highbush blueberry was more influenced by the thinning strength regardless of cluster or flower than internal quality of fruit such as solid and acid levels.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.429-433
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• 2010

The effects of 1-methylcyclopropene (1-MCP) for controlling ripening processes such as weight loss, fruit softening, soluble solids content (SSC), titratable acidity (TA), and fruit skin color were investigated and also the possibility that 1-MCP can inhibit the development of brown rot was explored in 'Formosa' plum ($Prunus$ $domestica$ L.). Fruit were treated with $1{\mu}L{\cdot}L^{-1}$ 1-MCP on the day of harvest and one day after harvest for 16 h at ambient temperature ($20^{\circ}C$), followed by 14 days of shelf life. 1-MCP treatment delayed fruit softening, weight loss and changes in skin color and TA during the shelf life period, but did not affect SSC. These 1-MCP effects were similar with and without delayed treatment. 1-MCP treatment inhibited the development of brown rot caused by $Monilinia$ $laxa$ during storage. Our data shows that treatment delays of ${\geq}1$ day before 1-MCP application had no negative effect of fruit softening, fruit skin color, and TA at ambient temperature ($20^{\circ}C$). Overall, these results indicate that 1-MCP can be used to maintain the quality of non-refrigerated plums.

• Korean Journal of Plant Resources
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• v.20 no.5
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• pp.461-465
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• 2007

In this study, changes in the overall antioxidant properties and chemical constituents including total phenolics and vitamin C of R. occidentalis fruit during ripening are studied. The antioxidant activity was measured by the free-radical scavenging activity(DPPH method) and reducing power(potassium ferricyanide method). Although, the weight and diameter of R. occidentalis fruit were increased with the progress of ripening, antioxidant activity and total phenolics were decrease during ripening. The highest free-radical scavenging activity(at $125{\mu}g/m{\ell}$) and reducing power(at $100{\mu}g/m{\ell}$) in fruit were 61.67% and 0.71, respectively. Total phenolic content and vitamin C content in fruit of 5 days after fruit set were $220.73{\mu}g/g$ and $540.45{\mu}g/g$, respectively. A linear correlation(r=0.9761) was shown between free-radical scavenging activity and total phenolic content.

• Proceedings of the ESK Conference
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• 1992.10a
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• pp.26-32
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• 1992

세계적으로 항공기 사고의 통계적 분석에 의하면 항공기 운용자의 인적과실(Human error)로 인한 항공기 사고가 약 70% 이상으로 보고되고 있다. 항공기 운용자의 인적과실에 기인한 요인들 중에서 운용자의 작업량, 작업공간, 작업환경, 인체크기, 인체 생리, 인간 심리 및 습관 등을 항공기 설계단계에서 고려하지 못한 요인이 대부분이다. 일반적으로 항공기 비행품질(Flying qualities)의 영향을 주는 설계분야는 크게 세가지로 항공기 형상(Configuration), 조종체계(Control system)및 조종실 배치(Cockpit layout)로 분류된다. 이들 세가지 설계분야 중에서 조종실의 운용자 인간공학적인 요구 사항을 고려하지 않으면 항공기 운용성 품질중에서 삼분의 일이 감소될 수 있다. 그리고 항공기 개발시에 전담하는 항공기 설계 분야별로 구분하고 그 전담설계 부서들과 인간공학적 조종실 설계 전담 부서가 항공기 비행 품질 및 운용자 인적과실(Human error)에 미치는 영향을 분석하고 인간공학의 중요성을 강조한다. 항공기를 개발할때에 개발자는 그 항공기를 운용하는 운용자의 인체, 생리, 심리, 습관 등을 고려 하여 항공기 조종실의 인간공학적 최적화 설계 및 배치 (Design and layout)를 개발초기단계부터 항공기를 설계할때에, 그 항공기의 조종실 품질은 조종사가 항공기 비행 임무를 수행할때에 항공기 비행을 위한 용이한 정보 인식(Sencing), 용이한 정보 결심(Deciding) 및 용이한 조종(Manipulating)의 특성을 조종사에게 제공할 때 항공기 비행 품질이 좋아질 것이다.

• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.4
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• pp.218-225
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• 2003

An analytical study was conducted in 2002 to observe the relationship between meteorological elements and the fruit quality of 'Tsugaru' apples at 8 orchards. The higher average air temperature in August made a higher content of soluble solids, but showed a lower anthocyanin content. As the average air temperature from April through August increased, flesh firmness decreased; and as the maximum air temperature from April through August increased, Hunter a value also decreased. Additionally, it was observed that the cytohistological characteristics of 'Tsugaru' apples were correlated with the average air temperature during the growing season. As average air temperature during the growing season increased, the epidermal layer of the fruit skin became thinner, starch density in the flesh decreased, intercellular space was larger, and tissue structure became looser.

• Research in Plant Disease
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• v.22 no.1
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• pp.18-24
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• 2016

This study was conducted to elucidate the cultural and pathogenic characteristics of Cladosporium cucumerinum PT1 and resistance of 81 commercial cucumbers (Cucumis sativus). Cucumber leaves and fruits appeared as scab were collected from a plastic film house located in Pyeongtaek, Gyeonggi-province, Korea in late March, 2015. A casual fungus was isolated from the diseased fruits on potato dextrose agar and it was identified as C. cucumerinum PT1 based on the morphological characteristics. To find out the effect of wounding and fruit size on the development of cucumber scab, small (<10 cm long), medium (10 to 20 cm long), and large (>20 cm long, commercially mature fruit) size cucumber fruits were harvested, C. cucumerinum PT1 pathogens were inoculated with a single droplet of suspension ($1{\times}10^5$ spores/ml) on wounded or unwounded cucumber fruits. Small fruits were completely damaged with showing severe water-soaking symptoms and fast pathogen growth regardless of wounded or unwounded. Meanwhile slight water-soaking symptoms on medium and large size fruits occurred and disease development into plant tissues was observed only on wounded fruits. Disease resistance of 81 commercial cucumber cultivars was evaluated on third-stage seedlings and small fruits by inoculating suspension ($1{\times}10^5$ spores/ml) of C. cucumerinum PT1. As a result, mini and pickling cultivar groups were resistant, 'Cheoeumcheoreom' cultivar was symptomless and the other cultivars were resistant to medium resistant. On the other hand, most of cucumber cultivars belonging to the other groups were susceptible. Disease resistance of cucumber against cucumber scab was significantly different among cultivars and a few cucumber cultivars showed different disease resistant responses to two bioassay methods using seedlings and small fruits. Therefore, to screen scab resistance in cucumber, a test using both fruits and seedlings is advisable. We think that the selected resistant cultivars can be used to control cucumber scab effectively under the farmhouse condition.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.138-139
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• 2003

감귤의 수확후 저장, 유통과정에서 부패 억제 및 약제 후숙처리 대체 효과를 얻기 위하여 환경친화적 방법으로서 제한적 열처리 기술의 적용 가능성을 확인하고자, 제주 서귀포산 조생종 온주 감귤의 열풍(hot air)처리에 따른 저장중 품질특성 변화를 살펴보았다. 상처가 없는 일정한 크기(약 120 g 내외)의 건전 과실을 선별한 후, 45$^{\circ}C$에서 2, 4, 6시간 동안 열풍을 가한 다음 5$^{\circ}C$에서 2시간 냉각하였다. 충분히 냉각시킨 과실을 통기성 천공 LDPE 필름에 포장하여 5$^{\circ}C$에서 3주, 18$^{\circ}C$에서 1 주간 저장하면서 생리적, 이화학적, 관능적 특성변화를 측정하였다. 열풍처리 직후 초기 호흡률은 처리구 모두 무처리구와 비교하여 높았으나 처리시간과는 유의적 상관성이 없었고, 저장중 처리구 감귤의 호흡률은 감소하여 21일째는 무처리구와 유사한 수준을 나타내었다. 과실내 기체조성은 처리구간에 차이를 보이지 않았으나 저장 21일부터는 저장온도 상승에 따라 $O_2$는 다소 감소하고 $CO_2$는 증가하는 양상을 보였다. 또한 과즙의 pH, 산도, 당 함량은 열처리에 의해 거의 영향을 받지 않았으며, 과실의 생체 중량감소율과 경도에서도 처리구간의 유의적인 차이를 구분할 수 없었다. 과피 표면색은 저장중 초기에 비해 다소 붉은 색으로 변하였으나, 6시간 처리구에서는 비교적 자은 노란색을 유지하였다. 한편 부패과 발생률에 있어서는 4시간 처리구가 축부병 등에 의한 짓무름 현상과 곰팡이 발생정도, 검은 썩음병에 따른 흑변 정도에서 저장중 가장 낮은 수준을 나타내었다. 그러나 관능적 평가에서는 열풍처리구와 무처리구 사이에서의 유의적인 차이를 발견할 수 없었다. 결과적으로 45$^{\circ}C$, 4시간이상의 제한적 열풍처리는 조생종 온주 감귤의 저장중 부패과 발생률을 현저히 감소시킴으로서 수확후 품질유지에 효과적인 열처리 조건임을 확인할 수 있었다.