• 원예과학기술지
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• 제32권3호
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• pp.340-345
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• 2014

Since the moisture content (MC) of growing medium closely related with the crop transpiration, the MC should be included to the environmental factors to be considered for irrigation control in soilless culture. The objective of this study was to analyze the transpiration of paprika plants using daily mean solar radiation (RAD) and vapor pressure deficit (VPD) as well as the growth of the plants at different MCs of rockwool growing media. The starting points of irrigation were controlled by a moisture sensor with minimum set points of 40%, 50%, and 60% of MCs. The canopy transpirations were measured for 80 to 120 days after transplanting and analyzed. The transpirations were well regressed with a combination of both RAD and VPD rather than daily mean RAD only under the controlled MCs. The transpiration at 60% MC was higher than those at 50% and 40% MCs. Leaf area, leaf fresh and dry weights at 60% MC were higher than those at 50% and 40% MCs while the number of leaves had no significant difference among the MCs. There were no significant differences in number of fruits and fruit size among all the MCs, while fruit weight was significantly lower at 40% MC than other treatments. Fresh and dry fruit yields were the highest at 60% MC. Therefore it was concluded that the transpiration was affected by the MC of rockwool growing medium and the minimum set point of 50-60% MC of rockwool growing medium gave better effects on the growth of the paprika plants.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1154-1154
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• 2001

Near infra-red (NIR) spectroscopy has been used for the non-invasive assessment of intact fruit for eating quality attributes such as total soluble solids (TSS) content. However, little information is available in the literature with respect to the robustness of such calibration models validated against independent populations (however, see Peiris et al. 1998 and Guthrie et al. 1998). Many studies report ‘prediction’ statistics in which the calibration and prediction sets are subsets of the same population (e. g. a three year calibration validated against a set from the same population, Peiris et al. 1998; calibration and validation subsets of the same initial population, Guthrie and Walsh 1997 and McGlone and Kawano 1998). In this study, a calibration was developed across 84 melon fruit (R$^2$= 0.86$^{\circ}$Brix, SECV = 0.38$^{\circ}$Brix), which predicted well on fruit excluded from the calibration set but taken from the same population (n = 24, SEP = 0.38$^{\circ}$Brix with 0.1$^{\circ}$Brix bias), relative to an independent group (same variety and farm but different harvest date) (n = 24, SEP= 0.66$^{\circ}$ Brix with 0.1$^{\circ}$Brix bias). Prediction on a different variety, different growing district and time was worse (n = 24, SEP = 1.2$^{\circ}$Brix with 0.9$^{\circ}$Brix bias). Using an ‘in-line’ unit based on a silicon diode array spectrometer, as described in Walsh et al. (2000), we collected spectra from fruit populations covering different varieties, growing districts and time. The calibration procedure was optimized in terms of spectral window, derivative function and scatter correction. Performance of a calibration across new populations of fruit (different varieties, growing districts and harvest date) is reported. Various calibration sample selection techniques (primarily based on Mahalanobis distances), were trialled to structure the calibration population to improve robustness of prediction on independent sets. Optimization of calibration population structure (using the ISI protocols of neighbourhood and global distances) resulted in the elimination of over 50% of the initial data set. The use of the ISI Local Calibration routine was also investigated.

• 한국농림기상학회지
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• 제5권4호
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• pp.218-225
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• 2003

본 실험은사과원의 위치에 따라 국지기후조건이 다양함을 보여주었으며, 이와 같이 다양한 기후환경은 과실의 품질에 직간접적으로 많은 영향을 미치고 있는 것으로 조사되었다. 즉, 당함량과 anthocyanin 함량은 8월의 평균기온에 따라 다른 것으로 나타났으며 일정한 상관관계를 가지고 있었다. 또한 4월에서 8월까지의 평균기온과 과육의 경도 사이에 일정한 상관이 인정되었으며, 4월에서 8월까지의 최고기온과 Hunter a값 사이에도 상관관계가 인정되었다. 이러한 기후조건의 범위는 세포조직학적 특성에도 영향을 미쳤으며, 온도는 과피층 세포의 수와 크기에 영향을 주었다. 따라서, 사과 주산지의 과실 품질은 기후의 영향을 크게 받아 매우 다양하게 나타나는 것으로 조사되었다.

• 생물환경조절학회지
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• 제17권2호
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• pp.124-131
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• 2008

본 연구에서는 감 재배지 간 과실 특성 차이에 관계한 기온 요인을 분석하고자 8개 단감 '부유' 재배지의 16개 기온요인과 과실 특성을 조사하여 주성분 및 다중회귀 분석을 실시하였다. 16개 기온요인 중 제1주성분은 12개 요인으로 이중 연 평균최저기온, 10월 평균기온, 연 평균최저극온, 생육기 평균기온의 영향력이 아주 높았다. 그리고 제2주성분은 4개 요인으로 4월에서 7월까지의 월 평균기온이었고 5월과 6월 평균기온의 영향력이 높았다. 이에 제2주성분까지 누적기여율은 91.4%로 재배지 간 기온 차이에 관여하는 기온 요인을 분석하는 데에는 충분하였다. 8개 재배지 중 5 재배지은 주요 기온요인이나 그 영향력에서 뚜렷한 차이를 나타내었다. 기온요인과 과실 특성 간 다중회귀분석에서 과고는 생육기 평균기온($X_8$) 겨울철 적산온도($X_6$) 영향을 뚜렷이 받으며 회귀식 $Y=150.55-5.375X_8+0.014X_6$을 나타내었고, 이 회귀식에 대하여 생육기 평균최저기온($X_9$), 적산온도($X_5$), 8월 평균기온($X_{12}$) 등이 영향을 주었다. 과경은 생육기 평균기온($X_8$, 부의 상관), 과육갈반정도는 생육기 평균최저기온($X_9$, 정의 상관), 과피색 $a^*$값은 연 평균최저기온($X_2$, 정의 상관)의 영향을 받는 것으로 나타났다.

• 농촌지도와개발
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• 제16권4호
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• pp.687-711
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• 2009

Recently, environmental-friendly agriculture (EFA) has been pointed out as an alternative for the change of our agricultural conditions. But the excessive amount of nutrients have been used to farmland since 1960s, when the intensive farming method called "High-Input, High-Yield" was expanded in earnest. This study was conducted to examine and compare farmers' purchasing and using fertilizer. For these purpose, data were gathered from a total of 326 farmers of the nation wide (greenhouse horticulture 60, upland cultivating 177, fruit-growing 89). The findings were as follows: First, 70.6% of greenhouse horticulture farmers, 89% of upland-cultivating farmers, 76.3% of fruit-growing farmers purchased fertilizer in Nong-hyup (farmers' cooperative organization). Second, only 54.2% of the greenhouse horticulture farmers, 60.2% of the upland cultivating farmers and 70.4% of the fruit-growing farmers recognized the optimum level of fertilizer. So, governmental organizations and agricultural technology center should carry out various programs for informing the farmers of the right way to use fertilizer and to practice EFA.

• 농업생명과학연구
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• 제50권2호
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• pp.53-59
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• 2016

Bacterial fruit blotch(BFB) of cucurbits caused by Acidovorax citrulli(Acc) continues to diminish fruit yields. The aim of this study was to address whether two genetically distinct populations of Acc are present in watermelon-growing fields in Korea. For this purpose, we used the enterobacterial repetitive intergenic consensus polymerase chain reaction(ERIC-PCR) profiling and substrate-utilization profiles. According to the results of ERIC-PCR, group I and II strains showed clearly differentiated PCR-based fingerprinting profiles. Differences between group I and II strains included amplification of unique, group-specific DNA fragments such as the 1.3-, 0.28-, and 0.25-kb fragments in ERIC-PCR. Acc stains belonging to group I did not use L-leucine, whereas group II strains did use the substrate. Our results support the genetic differentiation of Acc strains into two groups and demonstrate that Acc strains from both groups are previously existed in watermelon-growing fields in Korea. Information about the genetic diversity of Acc under the present study will help scientists and managers form strategies to control BFB.

• 생물환경조절학회지
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• 제13권2호
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• pp.73-80
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• 2004

한국 고추 주산단지에 '금탑', '부강' 품종을 1998년과 1999년에 재배하여 4회에 걸쳐 홍고추를 수확하였다. 고추의 과장, 과중, 건물율을 조사하고 색도를 분석한 후 고추 생육기간 동안의 지역별 온도 강우량 일조시간의 기상여건과 상관을 살펴보았다. 고추는 초기수확보다 후기로 갈수록 과장이 짧아지고, 과중은 가벼워지는 경향을 보였다. 두 품종간의 특성은 뚜렷한 차이를 보였으나 연도별 차이는 크지 않았다. 건물율은 수확시기가 늦어질수록 높아졌으며, 고추의 붉은색 비교를 위한 a${\times}$L값은 조사에서는 수확시기가 늦어질수록 높아지는 경향이 나타났다. 기상여건과 고추 과실 생장과의 상관관계를 살펴보면, 과장은 수확 전의 적산온도와 양의 상관이 있었다. 과중은 강우량과 수확직전의 적산온도와 상관이 있는 것으로 나타났다. 건물율은 수확 전 온도와 음의 상관을, 일조량과 양의 상관을 보였다. 붉은색 정도는 생육기간의 강우량과 음의, 일조와는 양의 높은 상관이 있었으며, 결정계수($r^3$)도 모든 외적품질 중 가장 높게 나타났다.

• 한국버섯학회지
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• 제9권2호
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• pp.69-73
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• 2011

1995년이후 부터 재배되어온 큰느타리버섯은 배양중 오염율 증가, 발이상태불량, 기형버섯의 발생, 수량 격감 등 이른바 연작장해로 불리어지는 재배상 문제점들에 대한 원인파악과 해결책이 요구되어, 발이상태 불량과 기형버섯 발생원인이 병원균과 발이 및 생육환경 관리방법에 있을 것으로 판단하고 병원균 종류 및 접종시기와 발이유기시 환기량에 따른 기형버섯 발생양상과 발이특징를 조사한 결과는 다음과 같다. 병원균 종류 및 접종시기별 배양율은 병원균 접종시기를 버섯종균접종과 동시에 접종할 때 44~63%로 낮았고, 병원균 종류별로는 Erwinia sp.+Peudomonas sp. 혼합 처리구에서 낮았다. 초발이소요일수는 발이유기시 환기를 충분히 시켰을 때($1,000{\pm}250ppm$) 병원균을 종균접종시 접종한 처리구에서 12~15일이 소요되었고, 나머지 다른 처리구에서는 10일로 동일하였으나, 환기량이 충분하지 않을 경우($2,000{\pm}250ppm$)모든 처리구에서 12~14일로 지연되는 경향이었다. 발이율은 발이유기시 환기량이 충분할 때, 종균접종시 병원균이 접종된 처리구에서 정상발이율이 29~56%로 낮았고, 나머지 처리구에서는 77~86%로 병원균 무접종 처리구 89%와 큰 차이가 없었으며, 환기량이 부족할 경우 병원균종류와 시기에 관계없이 병원균 무처리구를 포함한 모든 처리구에서 32~57%정도로 낮았다. 수량은 환기량이 충분할 때 병원균 무접종 처리구에서 83.8g/병으로 높았고, 종균접종시 처리구에서 10.9~28.2g으로 낮았으며, 병원균접종시기가 배양완료10일전, 발이유기시 처리구에서는 68.1~79.6g/병으로 병원균 무접종 처리구와 비슷하였다.

• 농촌지도와개발
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• 제23권2호
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• pp.145-156
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• 2016

The purpose of this study is to analyze the farms growing domestic kiwi fruit 'Gold' on their management performance and efficiency in order to reduce the risks involved with introducing new kind of crops for growing, and suggest improvements. First, the result of analysis showed that domestic kiwi fruit 'Gold' growers' income were higher than the average growers due to the fruit's high unit price and productivity. Second, the analysis of management efficiency resulted in scale efficiency having greater impact on inefficiency rather than pure technical efficiency. As for the analysis of technical efficiency, the depreciation costs of agricultural facilities had the greatest influence on its inefficiency. Third, inefficient farms put in excessive inputs across the board, while labor costs(self labor cost + hired labor cost) were the largest factor of optimal inputs according to the models of technical efficiency and pure technical efficiency. Fourth, because of greater reliance on mechanical tools from rising labor costs, there's a need for individual farms to avoid buying farming equipments and instead share the equipments of nearby farms and agricultural cooperatives, or start renting agricultural machines from companies.

• The Plant Pathology Journal
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• 제33권4호
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• pp.434-439
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• 2017

Incidence rates of diseases in kiwiberry orchards were investigated monthly from late June to late September in Gwangyang and Boseong in 2015 and 2016. The impact of postharvest fruit rot was investigated during ripening after harvest. Bacterial canker was only observed on one single tree in 2015, but black rot, powdery mildew, leaf spot and blight, and postharvest fruit rot diseases were problematic throughout the study period in both 2015 and 2016. Incidence rates of the diseases varied with kiwiberry cultivar, region and sampling time. Incidence rates of powdery mildew, leaf spot and blight diseases increased significantly during the late growing stages near fruit harvest, while black rot peaked in late August. Incidence rate of postharvest fruit rot on fruit without fruit stalks was less than half of fruit with fruit stalks, regardless of kiwiberry cultivars. Among the four cultivars, Mansu was relatively resistant to black rot and postharvest fruit rot diseases. In our knowledge, this is the first report of various potential pathogens of kiwiberry in Korea.