• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.4
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• pp.333-339
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• 2015

A thermal time-based phenology model of Kimchi cabbage was developed by using the field observed growth and temperature data for the purpose of accurately predicting heading and harvest dates among diverse cropping systems. In this model the lifecycle of Kimchi cabbage was separated into the growth stage and the heading stage, while the growth amount of each stage was calculated by optimal mathematical functions describing the response curves for different temperature regimes. The parameter for individual functions were derived from the 2012-2014 crop status report collected from seven farms with different cropping systems located in major Kimchi cabbage production area of South Korea (i.e., alpine Gangwon Province for the summer cultivation and coastal plains in Jeonnam Province for the autumn cultivation). For the model validation, we used an independent data set consisting of local temperature data restored by a geospatial correction scheme and observed harvest dates from 17 farms. The results showed that the root mean square error averaged across the location and time period (2012-2014) was 5.3 days for the harvest date. This model is expected to enhance the utilization of the Korea Meteorological Administration's daily temperature data in issuing agrometeorological forecasts for developmental stages of Kimchi cabbage grown widely in South Korea.

• Research in Plant Disease
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• v.15 no.3
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• pp.175-182
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• 2009

We investigated the effect of the infection times and infection degrees at transplanting time of Zucchini yellow mosaic virus (ZYMV) on the growth and yield of cucumber plants at the semi-forcing and the retarding culture in 2007. When cucumber was inoculated with ZYMV at transplanting time, 15, 30, 45, 60, and 75 days after transplanting, vine length, internode length, number of leaf of the plants and marketable yield largely decreased as the cucumber infected earlier. The regression models were obtained between the disease incidence levels at 20 days after transplanting as the inoculation degrees and the marketable yield of cucumber: y = $9333.1e^{-0.0317x}$ ($R^2$ = 0.8946) at the semi-forcing culture and y = $14695e^{-0.0303x}$ ($R^2$ = 0.8735) at the retarding culture. And the cucumber yield loss regression models between the symptoms incidence days from the final harvesting time and the rates of yield decrease were expressed as y=1.0851x - 6.7067 ($R^2$ = 0.9567) at the semi-forcing culture andy=1.0439x + 2.1321 ($R^2$ = 0.9674) at the retarding culture.

• Journal of Bio-Environment Control
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• v.15 no.2
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• pp.204-210
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• 2006

The purple color in flesh of 'Jasim' potato (Solanum tuberosum L.) tubers is due to an accumulation of anthocyanin. The experiment was conducted to determine what is the key factor among cultural environments that affect the accumulation of anthocyanin in 'Jasim' potato tubers, and the effect of nitrogen fertilization levels on that. Through analysis of anthocyanin content of purple-fleshed tubers produced under the different cultural environments of three localities and two planting dates, we determined that lower temperature during 30days before harvesting resulted in higher anthocyanin accumulation of 'Jasim' potato tubers. In the experiment of different level of nitrogen fertilization, 'Jasim' potato tubers produced in highland (Daegualryeong) showed higher content of anthocyanin in the treatment of recommended level than in treatment of lower or higher level as compared with the recommended level. However, significant difference of anthocyanin content among different nitrogen fertilization levels was not observed in lowland (Gangnung). These results suggest that the selection of locality or cropping system and the optimal fertilization management are very important factors for production of higher pigmented tubers in purple-fleshed potato.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.385-391
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• 2010

This study reports the results of natural enemy application against four insect pests on greenhouse sweet pepper in winter cropping system. Orius laevigatus ($3.3/m^2$) was released at two different times (Nov. 2005 & Feb. 2006) to control Frankliniella occidentalis, western flower thrips (WFT). Throughout the cropping season, the lowest level recorded of WFT was less than 2.0 individuals per yellow sticky trap. Amblyseius swirskii ($232.3/m^2$) was released four times (Nov. 2007 ~ Aug. 2008) to control Bemisia tabaci, tobacco whitefly (TWF). Until July 2008, TWF population had been suppressed lower than 6.6/trap. Phytoseiulus persimilis ($44.5/m^2$) was released seven times (Apr. 2008 ~ Aug. 2008) to control Tetranychus kanzawai, tea red spider mite (TRSM). As a result, TRSM population was suppressed lower than 1.7/1eaf. To control aphids, Aphidius colemani ($9.5/m^2$) was released seven times (Oct. 2004 ~ Jan. 2005), with the transplantation of banker plants ($5.5pot/660m^2$). As a whole, aphid's population has been successfully reduced to less than 2.0/leaf.

• Korean Journal of Weed Science
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• v.31 no.4
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• pp.375-383
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• 2011

This experiment was carried out to confirm characteristics of macro granule (GG) for herbicidal efficacy by using remote-controlled aerial application (RCAA) to control annual and perennial weeds in rice paddy field, and phytotoxicity to rice and non target plants of formulation types. Herbicidal efficacy of GG applied by using RCAA was 93.6~96.6% in flooded direct sowing cultivation. There was no difference in phytotoxicity between the hand and the power applicator methods in terms of height, number of tiller and yield component. Herbicidal efficacy of GG applied by using RCAA was 92.7~97.3% in machine transplanting rice field. There was no difference in phytotoxicity between the hand and RCAA methods in terms of height, number of tiller and yield component. When suspension concentrate (SC) and GG were applied directly on Chinese cabbage, lettuce, cucumber, pepper, soybean and wild sesame, several symptoms of injury such as, the inhibition of growth, yellowish, leaf fall and withering was observed.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.94-94
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• 2022

최근 밀(Triticum aestivum L.) 소비량이 꾸준히 증가하고 있어 국내 밀 자급률 증대를 위한 노력이 필요하다. 그러나 우리나라는 작물을 재배할 수 있는 농경지가 한정되어 있어 벼 수확 후 휴경 논을 이용하여 겨울철에 밀을 재배하거나, 하계 소득 작물과 연계하여 겨울철에 밀을 생산할 수 있는 방안을 모색할 필요가 있다. 본 연구에서는 남부지역 평야지 논을 이용하여 밭작물 중심 다모작 작부체계를 제시함과 동시에 밀을 재배하여 생육 특성과 수확량 변화를 살펴보았다. 단위면적당 수수 및 종실 수량은 작부이력에 밭작물이 포함된 다년 다모작 작형(들깨-IRG-참깨-밀, 콩-IRG-참깨-밀)이 다년 벼-밀 이모작이나 벼-IRG-참깨-밀 다모작에 비해 많았으며, 특히 들깨와 콩이 포함된 작부체계에서 많았다. 밀 품종 간 비교에서는 금강밀이 조경밀에 비해 출수기와 성숙기가 2~3일 빨랐지만 종실 수량은 100 kg/10a 이상 적어, 동일한 환경조건에서 조경밀이 금강밀에 비해 곡물 생산성 측면에서 유리할 것으로 보인다. 더군다나 조경밀은 조숙 다수성 경질밀로 전국에 재배가 가능하고, 단백질 함량이 높고 강력분의 특성을 보여 제빵용으로 많이 활용되고 있다. 본 연구에서 조경밀은 단백질이 10% 이하로 낮고 아밀로스는 28.4%로 높은데 반해, 금강밀은 단백질이 11.0%로 높고 아밀로스는 26.6%로 낮아 제과·제빵에 있어서, 금강밀이 좀 더 유용할 것으로 보인다. 밀가루의 Falling number는 조경밀과 금강밀 모두 350초 이상으로 높아 수발아로 인해 전분의 분해가 일어나지 않은 건전한 상태의 곡립임을 알 수 있다. 그리고 gluten 함량도 조경밀과 금강밀 모두 유사하게 높았으며, gluten 지수는 금강밀이 좀 더 높았다. 이상의 결과를 토대로 밀 수확량을 증가시키기 위해서는 기존의 벼-밀 이모작 보다 들깨-IRG-참깨-밀이나 콩-IRG-참깨-밀 등의 다년 다모작 작형이 좀 더 유리할 것으로 보인다.

• The Journal of Natural Sciences
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• v.6 no.1
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• pp.65-70
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• 1993

The objectives of this research are to survey the utilization types of radish and its adapted cultivars and to investigate the desirable traits in Japan. Many types of radish cultivars which hold diversified characteristics have been released according to the cropping type. Qualities and shape demanded in Japan was very different from Korean type radish cultivars. To meet the rapid require ment of our radish seed in Japan, we have to take the following measurements urgently: (1) to breed higher quality cultivars adapted for the utility of radish, (2) to secure various genetic resources of radish and (3) to develop cultivars resitant to specific pests and pathogens.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.93-96
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• 2012

'Double Shine', a cultivar of Gypsophila paniculata was newly developed for the cut flowers by Jeollabuk-do Agricultural Research & Extension Services. It has morphological characteristics of the spreading plant type, double florets of many petals and two pistils, emarginate petal tip and cup shaped calyx. Also 'Double Shine' has several traits such as strong flower stalk, bright colored flower, narrow branching angle and more or less resistance to powdery mildew and pest injury. Furthermore, 'Double Shine' produced higher primary branches, and longer flower stalk length with internodal length and than did a check variety 'Bristol Fairy' during summer cultivation in subalpine areas. Blooming of 'Double Shine' was delayed by 16 days, its floret had broader width, compared to 'Bristol Fairy'. Moreover, 'Double Shine' produced normal flowers with two pistils and 8.5 stamens, with little production of malformed flowers in the high temperature condition.

• Horticultural Science & Technology
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• v.29 no.5
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• pp.500-502
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• 2011

'Dream Pink', a cultivar of Gypsophila paniculata was newly developed for cut flowers by Jeollabuk-do Agricultural Research & Extension Services. It has morphological characteristics of the intermediate plant type, double florets with many petal and two pistils, emarginate petal tip and campanulate calyx shape. Also 'Dream Pink' had several other traits such as strong flower stalk, deep pink flower color, resistance to powdery mildew and pest injury. Furthermore, 'Dream Pink' produced higher number of nodes, primary branches, longer flower stalk length with long intermodal length. In subalpine area, 'Dream Pink' cultivar showed narrow branching angle as compare to 'My Pink', during the summer cultivation. Blooming in 'Dream Pink' was delayed by 5 days, its florets were broader with more number of petals as compare to 'My Pink'.

• Journal of the Korean Data and Information Science Society
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• v.28 no.3
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• pp.617-624
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• 2017

The production of cabbage, which is mainly cultivated in open field, varies greatly depending on weather conditions, and the price fluctuation is largely due to the presence of a substitute crop. Previous studies predicted the production of cabbage using actual weather data, but in this study, we predicted the wholesale price using unstructured agricultural meteorological data on the web. From January 2009 to October 2016, we collected documents including the cabbage on the portal site, and extracted keywords related to weather in the collected documents. We compared the forecast wholesale prices of simple models and unstructured agricultural weather models at the time of shipment. The simple model is AR model using only wholesale price, and the unstructured agricultural weather model is AR model using unstructured agricultural weather data additionally. As a result, the performance of unstructured agricultural weather model was has been found to be more accurate prediction ability.