• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.3
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• pp.254-260
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• 2015

Changes of the growth, quality and physiological response of Chinese cabbage cv 'Chunkwang' in response to five different temperature treatments based on climate change scenario were investigated during the growing season. The treatments consisted of normal year temperature $-2.0^{\circ}C$ (I), normal year temperature (II; Control group), normal year temperature $+2.0^{\circ}C$ (III), normal year temperature $+4.0^{\circ}C$ (IV), and normal year temperature $+6.0^{\circ}C$ (V). Regarding fresh weight, number of leaves, and leaf area were high in group IV, and V before the head formation stage, but it has decreased during the later growth period. Rate of frangibleness sympton was the highest in group V as 85.7%, and it was decreased in group IV (64.3%), group III (28.6%), group II (14.3%), and group I (7.1%). Regarding photosynthetic rate, group III, IV, and V showed relatively high photosynthetic rate at 20 DAP but it was reduced dramatically during the later growth period. Transpiration and stomatal conductance showed the similar trend with the photosynthetic rate. When comparing the chlorophyll fluorescence reaction of each treatment group at 50 DAP, Fv/Fm in group I was highest as 8.04 among all treatment groups and the lowest in group IV as 7.15.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.179-187
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• 2016

This study was conducted to determine the impact of elevated temperature and $CO_2$ concentration based on climate change scenario on growth and fruit quality of pepper (Capsicum annuum L. cv. Muhanjilju) with SPAR (Soil Plant Atmosphere Research) chamber. The intraday temperatures of climate normal years fixed by $20.8^{\circ}C$ during the growing season (May 1~October 30) of climatic normal years (1971~2000) in Andong region. There were treated with 4 groups such like a control group (ambient temperature and 400ppm $CO_2$), an elevated $CO_2$ group (ambient temperature and 800ppm $CO_2$), an elevated temperature group (ambient temperature+$6^{\circ}C$ and 400ppm $CO_2$) and an elevated temperature/$CO_2$ group (ambient temperature+$6^{\circ}C$ and 800ppm $CO_2$). Compared with the control, plant height, branch number and leaf number increased under the elevated temperature and elevated temperature/$CO_2$ group. However, leaf area and chlorophyll content showed a tendency of decreasing in the elevated temperature group and elevated temperature/$CO_2$ group. The number of flower and bud were decreased in the elevated temperature and elevated temperature/$CO_2$ group (mean temperature at $26.8^{\circ}C$) during the growth period. The total number and the weight of fruits were decreased in the elevated temperature group and elevated temperature/$CO_2$ group more than the control group. While the weight, length and diameter of fruit decreased more than those of control as the temperature and $CO_2$ concentration increased gradually. This result suggests that the fruit yield could be decreased under the elevated temperature/$CO_2$ ($6^{\circ}C$ higher than atmospheric temperature/2-fold higher than atmospheric $CO_2$ concentration), whereas the percentage of ripen fruits after 100 days of planting was increased, and showed earlier harvest time than the control.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.1
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• pp.57-65
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• 2012

This work attempted to study the properties of expression of ground, the composition of outlook and the implications of the connotative symbolic scenery throughout investigating the properties of expression content and method of the scenery, outlook, viewpoint, natural features for each drawing and intention of making 4 old maps, which had been made in the period of the Great Korean Empire and had been called 'Wansan-dohyoung(完山圖形),' 'Jogyeongdan- bigak-jaesil-dohyoung(肇慶壇碑閣齋室圖形),' 'Jeonju-geonjisan-dohyoung(全州乾止山圖形)' and 'Jogyeongmyo-gyounggijeon-dohyoung(肇慶廟慶基殿圖形),' and analyzing the correlation between their drawings. For this aim, observatory investigation by using a map, on-spot investigation, analysis involving the satellite images and internet were carried out with literature review simultaneously. The result of investigation could be sum up as follows. Gyounggijeon(1410), Jogyeongmyo(1771) and Jogyeongdan(1899), where are the core space to lay the historically firm foundation for securing the fact Jeonju is the home of the Royal Family of Joseon, had been built, fixed and extended for giving legitimacy to the Joseon Dynasty and a part of strengthening of royal authority. And these had played an important role of spiritual mainstay from early in the Joseon Dynasty to the era of the Great Korean Empire and had been managed and maintained continuously. It is grasped that the 4 maps consist of Sanhyuoungdo(山形圖; a kind of a mountain map), which is the map for showing a burial place of Lee Han(李翰), the founder of the Joseon Dynasty, and its auxiliary drawings and these had been drawn intensively to justify dignity and authority of the Imperial Family and the Emperor after the name of country was renamed the Great Korean Empire as a part of national undertaking. In detail, Wansan-doghyoung is the key map for announcing the existence of Jogyeong-myo, Gyounggijeon and Jogyeongdan in Jeonju and informing their locations and Geonjisan-dohyoung is the map of divination based on topography for highlighting the geomantic justification of the founder's mausoleum. Jogyeongdan-bigak-jaesil-dohyooung is the partial map detailing for Geonjisan-dohyoung. Jeonju-geonjisan-dohyoung and Jogyeongmyo-gyounggijeon-dohyoung had employed the binary reduced scale and the bird-eye view method and in the above maps, Geonji Mountain is the main mountain and these maps make an exaggeration of the main geographical features, centering Wangjabong and Euimyoso, unlike the real geographical features. Also, the other main geographical features, which are found in the burial place, are expressed in detail by changing the view. In the point of view of 1 set being consisted of 4 maps, 'Wansan-dohyoung' has the property not only as Gunhyoundo, which Gun and Hyoun mean a unit of the administrative district, respectively and Gynhyoundo is a kind of the map for recording their locations, but also as the map of showing their locations. On the other side, 'Jogyoungmyogyounggijeondohyoung' is a kind of lay-out drawing as a partially detailed map. In addition, it has been found out that 'Jeonju-geonjisan-dohyoung' and 'Jogyeongdan-bigak-jaesil-dohyoung' is not only Pungsu- hyounggukdo having the function of Sanhyoungdo but also a detail drawing. On the base of these properties, it is considered that the functionality as a serial map had been strengthened, unlike the existing old maps.

• Research in Plant Disease
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• v.25 no.1
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• pp.22-28
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• 2019

This study researched the current occurrence status of viral diseases of solanaceous crops in the main production areas of Gangwon region, for four years from 2014 to 2018. From 2014 to 2018, in eight cities and counties including Chuncheon, CMV, BBWV2, PMMoV, TSWV, and PVY occurred in chilli peppers. In case of tomato, the research was performed in 2017 and 2018 while TSWV and TYLCV were verified in Chuncheon, Hoengseong, and Cheorwon. Especially, TYLCV occurred in Chuncheon region for the first time in 2017, which was verified in 2018. Lastly, the current occurrence status of viral diseases of bell peppers was researched in seven cities and counties like Gangneung, Hoengseong, and Cheorwon from 2015 to 2018. In the results, CMV, BBWV2, PMMoV, PepMoV, and TSWV were verified in bell peppers of Gangwon region. During the research period, there were no crops suspected or infected by BWYV, so that it is judged that there is no villiferous or infected aphid by this virus in Gangwon-do. Such results of this study could be used as the basic data for the stable production of crops through the early prevention of plant diseases occurring in the solanaceous crops of Gangwon region.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.398-403
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• 2023

Process-based K-cabbage model is based on physiological processes such as photosynthesis and phenology, making it possible to predict crop growth under different climate conditions that have never been experienced before. Current first-stage process-based models can be used to assess climate impact through yield prediction based on climate change scenarios, but no comparison has been performed between big data obtained from the main production area and model prediction so far. The aim of this study was to find out the direction of model improvement when using the current model for yield prediction. For this purpose, model performance evaluation was conducted based on data collected from farmers growing 'Chungwang' cabbage in Taebaek and Samcheok, the main producing areas of Chinese cabbage in highland region. The farms surveyed in this study had different cultivation methods in terms of planting date and soil water and nutrient management. The results showed that the potential biomass estimated using the K-cabbage model exceeded the observed values in all cases. Although predictions and observations at the time of harvest did not show a complete positive correlation due to limitations caused by the use of fresh weight in the model evaluation process (R²=0.74, RMSE=866.4), when fitting the model based on the values 2 weeks before harvest, the growth suitability index was different for each farm. These results are suggested to be due to differences in soil properties and management practices between farms. Therefore, to predict attainable yields taking into account differences in soil and management practices between farms, it is necessary to integrate dynamic soil nutrient and moisture modules into crop models, rather than using arbitrary growth suitability indices in current K-cabbage model.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.4
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• pp.402-412
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• 2023

To cope with climate change, we compared the quality of naked oats (Avena sativa L.) cultivated in different regions. Naked oats were collected from domestic farms in different cultivation regions grouped as G1 and G2 for 3 years (2020-2022). The appearance, quality, and nutritional and functional compounds in the samples were assessed. In terms of appearance quality, the brightness and yellowness of the samples from the G1 region were significantly lower than those of the samples from the G2 region in 2020; however, no differences were observed between cultivation regions in the other 2 years. The results of testing the vitality of naked oats seeds showed that the electrical conductivity value was significantly lower in the samples from the G1 region than in those from the G2 region only in 2022. Among the nutritional components, moisture content was higher in the G2 region than in the G1 region over all 3 years, and the crude protein content was significantly higher in the G2 region than in the G1 region over all years. Carbohydrate content was significantly higher in the G1 region than in the G2 region in all 3 years and was inversely proportional to the crude protein content. The crude fat content tended to be significantly higher in the G1 region than in the G2 region, except in 2022. The levels of beta-glucan, a functional compound rich in naked oats, ranged between 3.4% and 4.2%, and except in 2020, there was no significant difference between cultivation regions. In addition, the content of avenanthramides, representative functional compounds that exist only in oats, was assessed. Over 2 years, in 2021 and 2022, the avenanthramide content was in the range of 2.4-20.7 ㎍/g and tended to be significantly higher in the G2 region than in the G1 region in both years. According to a survey of the average and minimum temperatures during the growing season of naked oats from 2020 to 2022, the average and minimum temperatures in January in the G2 region, which is the cultivation-limit area, were similar to those in Haenam in the G1 region. In conclusion, differences in nutritional and functional compounds were observed in naked oats grown in different cultivation areas. Therefore, considering the cultivation area of naked oats is expanding because of climate change, changes in the compounds that affect quality should be investigated.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.3
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• pp.49-82
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• 1965

For the stable and high yields of low-land rice in Korea, the characteristics of rice plant for the vegetative and physiological responses, plant type formation, and yield components have been studied in order to obtain the fundamental data for the improvement of cultural practices, especially for the ideal fertilizer application. Furthermore the environmental conditions in Korea including temperatures, light, precipitation, and soil conditions have been compared in the broad sense with those in Japan, and the application of nitrogen, phosphorus, potassium, silicate and other micro-nutrients were described in relation to the characteristics of environmental conditions for the improvement of fertilizer application. 1. The average yield of polished-rice per 10 are in Korea is about 204 kg and this values are much less than those in Japan and Taiwan where they produce 77% to 13% more than in Korea. The rate of yield increase a year in Korea is 4.2 kg, but in Japan and Taiwan the rates of yield increase a year are 81 % and 62%, respectively. It was also found that the coefficient of variation of yield is 7.7% in Korea, 6.7% in Japan and 2.5% in Taiwan. This means that the stability of producing rice in Korea is very low when compared with those in Japan and Taiwan. 2. It was learned from the results obtained from the 'annual yield estimation experiment' that there are big differences in the respect of plant type formations between rice crops grown in Japan and Korea. The important differences found were as follows: (1) The numbers of spikelets per 3.3 square meters are 891 in Korea and 1, 007 in Japan(13% more than in Korea). (2) The numbers of tillers per 3.3 square meters at the stage of maximum tillering are 1, 150 in Korea, but in Japan they showed 19% more than in Korea. (3) The ratio of effective tillers to total tillers is 77.5% in Korea and 74.7% in Japan, which seems to be higher in Korea than in Japan. But the ratio in Korea is very low when considered the numbers of total tillers in both countries. (4) The ratio of grain to straw is 85.4% in Korea and 96.3% in Japan. 3. The average temperatures during the growing season at the area of Suwon, Kwangjoo and Taegu are almost same as those in the district of Jookokoo(Fookoo yama) in Japan, i.e., the temperatures during the rice-growing season in Korea are similar to those in the southern-warm regions of Japan. 4. Considering the minimum temperatures at the stage of limiting transplanting, 13$^{\circ}C$, the time of transplanting might be 30 to 40 days earlier than presently practicing transplanting time, which comes around June 10. 5. The temperatures during the vegetative growth in Korea were higher than those temperatures that needed in the protein synthesis which ate the main metabolism during this stage. However, the temperatures at the time of reproductive growth was lower than the temperatures that needed in the sugar assimilation which is main metabolism in this stage. In this point of view, it might be considered that the proper time of growing rice plant in Korea would be rather earlier. 6. The temperatures and the day light conditions at the time of first tillering stage of rice plant, when planted as presenting transplanting practices, are very satisfactory, but the poor day light length, high temperatures and too wet conditions in the time of last-tillering stage(mid or last July) might cause the occurrence of disease such as blast. 7. The heading stage of rice plants at each region through nations when planted as presently practicing method comes when the day light length is short. 8. It was shown that the accumulated average air-temperature at the time of maturing stage was not enough and the heading time was too late, when considered the annual deviations of mean temperatures and low minimum temperatures. 9. The nitrogen content of each plant part at the each growing stage was very high at the stage of vegetative growth when compared with the nitrogen content at the stage of reproductive growth after heading. In this respect it was believed to be important to prevent the nutrient shortages at the reproductive stages, especially after the heading. 10. The area of unsatisfactory irrigation paddy fields and natural rain-fed paddy fields are getting reduced in Korea. The correlation between the rate of reducing unsatisfactory irrigation and natural rain-fed paddy fields and the rate of yield increase were computed. The correlation coefficients(r) between the area of unsatisfactory irrigation paddy fields and yield increase were +0.525, and between the natural rain-fed paddy fields and yield increase, +0.832 and between the unsatisfactory irrigation plus natural rain-fed paddy fields and yield increase, +0.84. And there were. highly significant positive correlations between natural rain-fed paddy fields and yield increases indicating that the less the area of natural rain-fed paddy fields, the greater the yields per unit area. 11. The results obtained from the fertilizer experiments (yield performance trials) conducted in both Korea and Japan showed that the yield of non-fertilized plots per 10 are was 231 kg in Korea and 360 kg in Japan. On the basis of this it might be concluded that the fertility of soil in Korea is lower than that in Japan. Furthermore it was. also found that the yields of non-nitrogen applied plots per 10 are were 236 kg in Korea and 383 kg in Japan. This also indicates that the yields of rice in Korea are largely depending on the nitrogen content in the soil. 12. The followings were obtained when the chemical natures of soils in both Korea and Japan were compared. (1) The content of organic matter, total nitrogen, exchangeable calcium, and magnesium in Korea were no more than the half those in Japan. (2) The content of N/2 chloride and soluble silicate in low-land soil were on the average lower in Korea. (3) The exchange capacity of bases in Korea was no more than half that in Japan. 13. It was also observed by comparing the soil nature of the soil with high yielding capacity with the soil with low yielding capacity that the exchange capacity of bases, exchangeable calcium and magnesium, potassium, phosphorus, manganese, silicate and iron were low in the soil with low yielding capacity. 14. The depth of furrow slice was always deeper in the soil with high yielding capacity, and the depth of furrow slice in Korea was also shallower than that in Japan. 15. Summarizing the various conditions mentioned previously and considering the effects of silicate and trace elements such as manganese and iron besides three elements on the physiological and plant type formation of rice crops, more realistic and more ideal fertilizing practices were proposed. proposed.