• Korean Journal of Organic Agriculture
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• v.25 no.3
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• pp.619-630
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• 2017

In recent years, not only the cultivation area of Jujube in Korea but also the number of pest species has increased. The farmers farming environmentally friendly are in great difficulty because there are no effective control devices. This study was conducted to investigate the control effect of the insect screen net on three pest species (Apolygus spinolae, Dasineura sp. and Carposina sasakii) in Jujube orchard when the pests were blocked by insect screen net. For the first and second surveys, the damage rates by A. spinolae were 9.06, 13.95% in 50 mesh, 4.75, 10.17% in 25 mesh, 5.68, 11.84% in 18mesh mesh of insect screen net and 21.6, 36.34% in untreated insect screen net, respectively. The damage rates by Dasineura sp. were 0.54, 0.13% in 50 mesh, 0.93, 2.84% in 25 mesh, 1.05, 13.45% in 18 mesh mesh of insect screen net and 11.1, 26.65% in untreated insect screen net. Carposina sasakii were completely blocked in all the treatments. Damages on Jujube were not observed by insect screen net. Therefore, insect screen net is effective on insect pest control for Jujube.

• Korean Journal Plant Pathology
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• v.13 no.3
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• pp.145-151
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• 1997

An unusual young fruit rot of apple caused by two species of Phytophthora was epidemic from late May to early July of 1996 in Andong, Uisung and Chungwon areas of Korea. The disease spread to over 30 apple orchards in the areas and percent of the infected tree and fruit was ca. 10~90% and 1`15%, respectively. Water soaking lesions or spots on leaves and shoot blight were also developed by the pathogen. Among 39 isolates collected, 25 were identified as P. cactorum and the others were as zp. cambivora on the basis of their distinctive morphological characters. While the former fungus was homothallic, all isolates of the latter were A1 mating types. Koch's postulate was fulfilled. Both fungi showed strong pathogenicity not only to young fruits, leaves and shoots of apple but also to those of pear and peach. Several vegetables tested did not show symptoms even by wound inoculation. An Occurrence of young fruit rot of apple caused by Phytophthora has not been reported in Korea, especially, P. cambivora has not been recorded previously as the causal agent of the disease in the world.

• Food Science and Preservation
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• v.11 no.3
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• pp.342-346
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• 2004

Chemical components in the peel and flesh of full riped trifoliate oranges(Poncirus trifoliata) were investigated. Contents of crude protein, crude fat and ash in peel and flesh were 5.15 and 3.31$\%$, 3.82 and 6.65$\%$, 2.62 and 2.09$\%$, respectively. Vitamin C contents were 4.70 mg$\%$ in peel and 70.93 mg$\%$ in flesh. Free sugars were fructose, glucose and sucrose, the level of each or total free sugars was twice higher in peel than in flesh. Organic acids were citric acid, malic acid and oxalic acid, the total contents in peel and flesh were 0.35 and 1.25$\%$, respectively. Free amino acids were aspartic acid, histidine, tyrosine, arginine, valine, lysine, ammonia, cysteine, alanine, glutamic acid, isoleucine, leucine in peel, and lysine, valine, ammonia, arginine, tyrosine, isoleucine, methionine, leucine, histidine, phenylalanine in flesh.

• The Korean Journal of Air & Space Law and Policy
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• v.19 no.2
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• pp.137-162
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• 2004

Generally the aircraft accident caused a great loss of lives, severe property damages including aircraft's total loss and thus, affect enormous emotional and economic damages to the public. We, therefore, should try every efforts to prevent the re-occurrence of aircraft accident by examining the cause of accident closely and discovering it through aircraft accident investigation. Though the object of an accident investigation is not to apportion blame but to discover a cause or causes of an accident to prevent future accidents, the cause of an accident would play a vital role in determining the liability of the carrier, legal relationship with the third party and jurisdiction, etc. in the aviation litigation. Therefore, it is very important that aircraft accident investigation are carried out by a professional and independent agency. Also, it needs for us to be careful in applying investigation results in the courts not to be deterrent to discovering the cause of accident. Korea now has the Aviation Accident Investigation Agency Board under the Korean Ministry of Construction and Transportation, but unfortunately it is often pointed out that it lacks professionalism and independency due to the bureaucratism of the Government. We, therefore, should establish a professional and independent aircraft accident investigation agency like United States' NTSB and reflect the issues mentioned-above on the new Act.

• Horticultural Science & Technology
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• v.35 no.4
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• pp.393-401
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• 2017

One-year old pear (Pyrus pyrifolia L.) trees of a new commercial cultivar 'Manpungbae', recently developed in South Korea, were planted in 2001 (planting year 1) and trained to four trellis systems: Y-trellis, Y-II-trellis, pergola, and vase-pergola. To evaluate training systems in the local area (southern Korea), tree growth responses were compared for each trellis system from planting years 3 to 8. For trees trained to Y-trellis and pergola systems, a high proportion of land covered by tree canopy was maintained over the study duration, with 70-80% coverage in year 8. Eight-year cumulative yield per tree was increased in the vase-pergola system with a low planting density and an additional scaffold. Compared with other systems, cummulative yield use efficiency was greatest in Y-II-trellis and pergola systems in years 5 and 8. Compared with Y-II-trellis and vase-pergola systems, the 8-year cumulative yield per hectare was two fold greater for trees trained to the Y-trellis (103 tons) and pergola systems (101 tons). Use of the pergola system improved average fruit weight and fruit soluble solid contents, as well as net income in year 8. Given that we observed reduced fruit productivity and increased labor hours (pruning and orchard work), we consider the Y-trellis and pergola systems to be less valuable trellis systems than the others evaluated.

• Korean Journal of Organic Agriculture
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• v.24 no.4
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• pp.773-786
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• 2016

Grape cultivar "Campbell Early" account for 70% of table grape in Korea and Leaf Spot Disease caused by Pseudocercospora vitis is one of a major disease in greenhouse and field grown area during late summer season in both of organic and conventional grape farm. Leaf spot disease can cause lowing of sugar content in fruit and vine growth and very difficult to control especially in organic field. Photosynthesis ability and chemical components are compared between leaf spot disease infected leaves with degree of necrotic area. With increase of disease necrotic area, $CO_2$ differential value, water use efficiency and $CO_2$ assimilation and respiration ratio are decreased proportionally and on the other hand, stomatal conductance value is not affected by disease necrotic area. Chlorophyll contents are also decreased by 50% in heavily infected leaves and imply decrease of chlorophyll contents is a major source of photosynthesis ability decline. With increase of disease necrotic area in leaves, total nitrogen and phosphate contents are decreased and on the other side, total carbon, potassium, calcium and magnesium contents are increased. From this research, we can infer that not only chemical control program is important in control of leaf spot disease but also fertilizing program is significant especially in organic agronomical control of fungal disease in grape cultivar "Campbell Early".

• Journal of Bio-Environment Control
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• v.29 no.1
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• pp.62-72
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• 2020

The purpose of this study was to investigate the quality characteristics of ripe fruit based on harvest date and to examine the ripening phase of 'Seolhyang' strawberry suitable for room temperature, cold-chain, and low temperature distribution. The strawberries were harvested six times between December 20 to May 9. The appropriate maturity of strawberries is characterized by the firmness of approximately 2.9-3.0 N, and SSC remained above 8.6 °Brix until March and declined after April. The quality index values that determine the maturity stage of strawberries should be red color, Hunter a value ranging from 32 to 37, and hue angle of 36-45℃. For the after-ripening experiment, the progression rate of the ripening stage determined based on strawberry color was 10%/day at room temperature, 5%/day at 10-12℃, and 3%/day at 5℃. Thus, strawberries should be harvested at 80% coloring stage for distribution at room temperature and at least 90% for low temperature storage to maintain the merchantability. Besides, strawberries harvested at 70% coloring stage at room temperature and strawberries harvested below 80% coloring stage at low temperatures below 5℃ had lost commercial value before reaching 100% coloring stage.

• Horticultural Science & Technology
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• v.30 no.6
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• pp.784-787
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• 2012

'Gwanha' is new strawberry (Fragaria ${\times}$ ananassa Duch.) cultivar, which was released by Highland Agriculture Research Center, Rural Development Administration, in 2011. In 2007, this cultivar was originated from a cross between 'Sucambodiaberry' and 'Selva' that showed excellent ever-bearing characteristics including continuous pink flowering habit under long-day and high temperature condition. It was named 'Saebong No.4' after examining its characteristic and productivity in summer culture from 2009 to 2011. After characteristic and productivity test in 2011, 'Gwanha' was selected as an elite cultivar. The general characteristics of 'Gwanha' include spreading type, middle vigor, elliptic leaf, and long cluster in growth. The fruit shape is wedge, and the red fruit is edible and unique among the domestic ornamental strawberry cultivars. Flower color of 'Gwanha' is pink, and flower cluster is more appearance than 'Pinkpanda'. The average fruit weight of 'Gwanha' is about 7.8 g and the marketable yield is relatively low because of low marketable rate. It is resistant against fusarium wilt. 'Gwanha' is suitable for four season cultivation as an ornamental strawberry cultivar because it shows continuous flowering habit under long-day and high temperature condition.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.787-791
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• 2012

Bloods from slaughtered Korean native cattle (Hanwoo : Bos taurus coreanae) can be used in agriculture with various beneficial effects on the environment. This study was performed to find out the effect of the application of calcium and germanium, which are chelated with peptides made of cattle bloods on the absorption of them by cherry tomato (Lycopersicon esculentum Mill.). Peptide was purified by enzymatic hydrolysis and ultrafiltration from serum protein, which is composed of Asp, Glu, Lue etc. Chelated Ca and Ge were produced by reacting the peptide with $CaCl_2$ and Ge-$132^{(R)}$. Then, they were applied to cherry tomato during cultivation period at the rate of $300mL{\times}3times$ (10 days interval) for each tomato tree. Application of chelated-Ca increased the Ca contents in leaves and fruits of cherry tomato showing as 19.9% and 23.4% in newerly prepared chelated-Ca-200 ($200mg\;L^{-1}$), 8.1% and 6.8% in commecrial Calciolid Ca-300 ($300mg\;L^{-1}$) compared to 3152.6 and $63.2mg\;kg^{-1}$ in control, respectively. Application of chelated-Ge showed the increase in the germanium contents in both leaves and fruits of cherry tomato by over 6 times than those of control and over 4 times than Ge $132^{(R)}$-20 application. As a result of this study, it seemed that the application of chelated-Ca and chelated-Ge would be more effective than the existing commertial one in the absorption of calcium and germanium by cherry tomato.

• 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.132-132
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• 2003

포도 중 캠벨얼리 품종은 색이 검붉고 당도가 높아 우리나라 대표적인 품종 중에 하나로 알려져있다. 그러나 수확 후 저장 유통 중 품질이 저하되기 쉽다. 따라서 예냉 조건 및 수송, 저장, 유통조건에 따른 품질조사를 비교실험하여 가장 안전한 저장 유통 방법을 개발하고자 하였다. 실험재료는 2003년 8월20일경에 포도 주산지인 영천 농가에서 수화 한 후 바로 예냉처리를 하였다. 이때 사용한 예냉기는 원예연구소에서 개발한 시제작품을 사용하였다. 대조구로 무예냉을 두었으며 예냉 후 수송온도도 관행적인 상온과 저온(2$^{\circ}C$)로 구분 처리하였으며 저온온도별로도 함께 실험하였다. 포장단위도 2kg 와 5kg로 각각 처리하여 수행하였다. 예냉이 품질에 미치는 영향을 조사하기 위하여 예냉처리에 따른 호흡패턴 변화와 이화학적 특성변화를 조사하였다. 또한 저장 중 중량감소율, 부패율 및 탈립율을 조사하였다. 포도 ‘켐벨얼리’의 수확 시 품온 29.5$^{\circ}C$를 적정 저장 온도인 2$^{\circ}C$로 저하시키는데 일반 저온 저장고에서 10시간 정도 걸리는 데 반하여 차압예냉기 이용시 3시간으로 단축시킬 수 있었으며 예냉 포도의 처리구별 호흡량은 초기 6.65$m\ell$/kg/hr 였으나 상온무예냉 및 예냉 처리구의 경우에는 저장해가면서 급격히 증가되었고 저온에서는 무예냉의 경우에는 계속 증가되는 반면 예냉 처리구의 경우에는 포장 규격과는 상관없이 다른 처리구 보다 호흡억제 효과가 있었다. Ethylene 발생량 역시 호흡과 비슷한 경향을 보여 주어 예냉 시 과실의 품질 저하 요인 발생량을 억제시킬 수 있었다. 경도는 저장 기간이 경과됨에 감소되나 저온 예냉 처리구의 경우가 초기 1.26N을 높게 유지하였고 자연중량 감모율은 상온저장 2주째 무예냉처리구 8.40%로 감소된데 비하여 예냉 저온 수송 구의 경우에는 0.25%로 매우 낮았다. 포도 ‘켐벨얼리’의 저온 저장중 부패율은 저장 2주째 상온 무예냉 처리구의 경우 19.8%이었으나 저온 예냉 처리구의 경우는 부패과가 발생하지 않았고 탈립율 역시 상온무예냉처리구의 경우 53.5%인데 반하여 저온 예냉 처리구는 저장 4주경과 시까지 탈림과가 없었다. 당도 및 pH변화 역시 차압 예냉 후 저온 수송 처리구가 초기당도(12.0Bx)$^{\circ}$값과 초기 pH(3.8)를 저장 25일 경과시까지 유지하였다. 수확 시 높은 품온을 갖고 있는 과일을 산지에서 예냉 처리를 한 후 저온 냉장차를 이용하여 유통한다면 관행 유통 구조보다 고품질의 포도를 유통시킬 수 있는 것으로 사료되며 앞으로는 완숙된 고 당도(12.0~15.0Bx)$^{\circ}$ 포도를 수확 한 즉시 예냉 처리하고 저온 유통한다면 보다 신선한 과일을 소비자에게 전달 할 수 있을 것이다.