• 한국유기농업학회지
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• 제19권spc호
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• pp.129-130
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• 2011

• 한국식품영양과학회지
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• 제29권2호
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• pp.181-187
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• 2000

The contents of organic acid in Korean apple juice were analyzed by HPLC using YMC-peak ODS-AQ column and enzymatic assay. Model apple juices were prepared at the laboratory and commercial apple juices were purchased from the market. Individual organic acid contents were as follows: DL-malic acid 62~402mg%, L-malic acid 48~360mg%, citric acid 1.81~15.74mg%, fumaric acid nd~0.50mg%. Together, these tests gave useful information about the quality and authenticity of a particular apple juice smaple. The presence of D-malic acid was a clear indication of adulteration because this isomer did not occur naturally. Fumaric acid and citric acid levels above trace amounts were also inconsistent with pure apple juice.

• 원예과학기술지
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• 제34권5호
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• pp.708-718
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• 2016

Two different pest control programs were applied on 8-year-old 'Ryoka'/M.26 apple trees (Malus domestica Borkh.). Lime sulfur or Bordeaux mixture with emulsified oil were applied 12 times from late March to mid-September as organic treatment, and synthetic chemicals were 7 times applied as control treatment. Over the entire apple-growing season, photosynthesis rates of apple trees were significantly lower in the organic treatment than in the control, and this photosynthetic differences were larger in July and August. Photosynthesis-related parameters such as stomatal conductance and transpiration behaved similarly to photosynthesis. The leaf area in the organic treatment was significantly smaller ($24.7cm^2$) than that in the control treatment ($30.7cm^2$). Organic leaves contained significantly less Chl. a ($15.5mg{\cdot}g^{-1}$) than did control leaves ($17.6mg{\cdot}g^{-1}$). Fruit yield per tree was significantly lower in the organic treatment (18.8 kg) than in the control (24.5 kg), because organic fruits experienced a higher rate of disease infection such as white rot (Botryosphaeria dothidae) and bitter rot (Glomerella cingulata) than did control fruits. Organic fruits had high flesh firmness but less color development (lower Hunter's a values). In this experiment, the pest control program with frequent applications of organic fungicides showed negative effects on photosynthesis and disease infection on leaves and fruits, and thus reduce the fruit quality and yield in 'Ryoka'/M.26 apple trees.

• Journal of Applied Biological Chemistry
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• 제50권2호
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• pp.88-96
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• 2007

Organic farming systems based on ecological concepts have the potential to produce sustainable crop yields with no decline in soil and environmental qualities. Recent expansion of sustainable agricultural systems, including organic farming, has brought about need for development of sustainable farming systems based on value judgments for key properties of importance for farming. Chemical and microbiological properties were chosen as indicators of soil quality and measured at soil depth intervals of 5-20 and 20-35 cm in conventional and organic-based apple orchards located in Yeongchun, Gyeongbuk. The orchards were two adjacent fields to ensure the same pedological conditions except management system. Soil pH in organic farming was around 7.5, whereas below 6.0 in conventional farming. Organic farming resulted in significant increases in organic matter and Kjeldahl-N contents compared to those found with conventional management. Microbial populations, biomass C, and enzyme activities (except acid phosphatase) in apple orchard soil of organic farming were higher than those found in conventional farming. Higher microbial quotient ($C_{mic}/C_{org}$ ratio) and lower microbial metabolic quotient for $CO_2(qCO_2)$ in organic farming confirmed that organic farming better conserves soil organic carbon. Biological soil quality indicators showed significant positive correlations with soil organic matter content. These results indicate organic-based farming positively affected soil organic matter content, thus improving soil chemical and biological qualities.

• 한국환경농학회지
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• 제26권4호
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• pp.279-285
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• 2007

Soil physical properties in organic farming apple orchard were evaluated in relation to conventional farming to better understand the effects of organic farming system on soil quality. Two adjacent apple orchards, matched by soil type, were chosen to ensure the same pedological conditions except management system. Soil samples were collected from middle of two adjacent trees along the tree line at two depths of 5-20 and 20-35 cm in September 2006. Contents of organic matter in organic farming soil were twice as much as those found in soil of conventional farming. The higher level of organic matter in organic farming soil was reflected through a consequent trend in improved soil physical properties. Organic farming produced greater aggregation in >2 mm size and increased aggregate stability. Bulk density was lower by 13% and hence porosity was higher in soils of organic farming as compared with conventional farming. Water holding capacity was significantly greater with organic farming by >17% over conventional farming. The capacity of organic farming to improve soil physical properties can be contributed to the regular application of relatively large amount of organic materials and the sustainable ground-cover managements, mulching with compost and cover crop cultivation.

• 한국유기농업학회지
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• 제25권1호
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• pp.125-134
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• 2017

본 연구는 친환경 유기과원의 부란병 방제를 위한 유황토분의 효과를 검증코자 2년간 수행되었다. 제조된 유황토분의 사과 부란병 치유효과를 검증하기 위해 유기과원에는 석회유황합제의 처리와 비교하였으며, 관행과원에서는 석회유황합제, 유황토분 및 네오아소진을 처리하였다. 유기과원의 유황토분의 부란병 치유율은 대조구에 비해 뚜렷하게 유의성이 인정되었으나, 2013년 봉현 과원을 제외하고는 석회유황합제와는 큰 차이가 없었다. 유기과원의 과실품질조사 결과, 과피의 붉은 색은 대조구에 비해 석회유황합제 처리구에서 다소 높게 나타냈으며, 과실의 경도에서는 유황토분 처리구가 대조구에 비해 유의적으로 높게 나타났다. 관행과원에서의 유황토분, 석회유황합제 및 네오아소진 처리는 대조구에 비해 통계적 유의적으로 높게 조사되었다. 유황토분의 부란병 치유율은 유기사과과원 및 관행사과과원에서 87.5~97.5%인 것으로 조사되었다. 관행과원에서의 유황토분 처리는 신초생육에 있어 네오아소진에 비해 통계적 유의성이 있게 증가하였다. 과실품질의 경우 유황토분처리는 과실의 붉은 색의 증가를 보였으나, 다른 과실품질인 무게, 경도, 당도 및 적정산도에서 통계적 유의성을 나타내지 않았다.

• 한국유기농업학회지
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• 제19권spc호
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• pp.165-168
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• 2011

An organic apple (Malus ${\times}$ domestics Borkh.) orchard was established to study the interaction effects of ground cover management systems (GMS) and nutrient sources (NS) on soil and tree nutrient status and tree growth. Trees received one of four GMS: 1) green compost (GC), 2) wood chips (WC), 3) shredded paper (SP), and 4) mow-and-blow (MB). Across all GMS, one of three NS was applied: A) a commercial organic fertilizer (CF), B) poultry litter (PL), and C) control (NF). Overall, GMS had greater effects on the variables than did NS. GC mulch supplied greater nutrients, followed by WC, SP, and MB mulches. SP trees had lower foliar [N] in the first two years than the GC and WC trees. GC-and WC-treated trees had larger trunk cross sectional area than the SP and MB trees.

• 한국미생물·생명공학회지
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• 제9권3호
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• pp.139-143
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• 1981

사과 식초 제조 과정 중 유기산의 변화를 검토하기 위하여 사과즙을 알콜발효시킨 후 Acetobacter aceti와 이 균에 NTG와 UV의 처리로 하여 얻은 변이주를 접종하여 식초산 발효를 시켰을 때 제조과정별로 유기산의 조성과 함량을 gas chromatography로 분석하여 다음의 결과를 얻었다. 1. 사과 원료 중 유기산의 함량은 malic acid 0.73 %, citric acid 0.038%, acetic acid 0.067%이었다. 2. 사과즙을 알콜발효시켰을 때 유기산의 함량은 malic acid 0.114%, lactic acid 0.1%, acetic acid 0.08%이었다. 3. 모균주와 변이주를 이용하여 얻어진 발효식초의 유기산 조성에 있어서는 차이가 없었고 함량에서는 차이가 있었다. 4. 변이주의 초기산 생성능은 모균주에 비하여 약간 빨랐다.

• 한국토양비료학회지
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• 제33권6호
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• pp.393-397
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• 2000

퇴비의 시용량에 따른 사과의 수량과 토양화학성에 미치는 영향을 조사한 결과는 다음과 같았다. 사과원에 퇴비시용량의 증가에 의해 토양중의 인산함량 및 치환성 양이온의 함량이 증가하였으나, 유기물은 거의 변화가 없었다. 퇴비의 시용량이 증가할수록 사과의 수량은 증가하였으나, 경도 및 당도의 차이는 없었다. 화학비료를 감비처리하고 퇴비의 시용량을 높인 결과 퇴비의 시용량이 증가함에 따라 토양 중 유기물 및 Ca의 함량은 증가하였다.

• 한국유기농업학회지
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• 제6권1호
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• pp.35-43
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• 1997

For the purpose of acquiring microbial agents that can be utilized to billogically control the major airborne disease to apple trees, such as canker(Valsa ceratosperma), the effective microorgaisms were isolated, tested for antagonistic activity to the pathogen causing major disease to apple trees and identifed. Screening of more than 3, 000 species of microorganisms collected in nature for them antagonistic action to the pathogen, Valsa ceratosperma causing disease to apple tree resulted in selection of effective species. Out of the 11 species, one species designated as CAP141 demonstrated outstanding activity. The bacterial strain, CAP141 exerted antagonistic efficiency of 65% on Valsa ceratosperma. The CAP141 was identified as a bacterial strain to Bacillus subtilis based on morphology, culture conditions, and physio-biochemical characteristics.