• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.88-88
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• 2022

Detection of stress responses in crops is important to diagnose crop growth and evaluate yield. Also, the multi-spectral sensor is effectively known to evaluate stress caused by nutrient and moisture in crops or biological agents such as weeds or diseases. Therefore, in this experiment, multispectral images were taken by an unmanned aerial vehicle(UAV) under field condition. The experiment was conducted in the long-term fertilizer field in the National Institute of Crop Science, and experiment area was divided into different status of NPK(Control, N-deficiency, P-deficiency, K-deficiency, Non-fertilizer). Total 11 vegetation indices were created with RGB and NIR reflectance values using python. Variations in nutrient content in plants affect the amount of light reflected or absorbed for each wavelength band. Therefore, the objective of this experiment was to evaluate vegetation indices derived from multispectral reflectance data as input into machine learning algorithm for the classification of nutritional deficiency in rice. RandomForest model was used as a representative ensemble model, and parameters were adjusted through hyperparameter tuning such as RandomSearchCV. As a result, training accuracy was 0.95 and test accuracy was 0.80, and IPCA, NDRE, and EVI were included in the top three indices for feature importance. Also, precision, recall, and f1-score, which are indicators for evaluating the performance of the classification model, showed a distribution of 0.7-0.9 for each class.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1995년도 춘계 학술대회지
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• pp.14-15
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• 1995

• 한국작물학회지
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• 제37권5호
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• pp.449-460
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• 1992

본 시험은 유ㆍ무한신육형간의 생육 및 수량형질의 차이와 그 변이정도를 구명하여 콩 육종과 재배의 기초자료를 얻고자 '89년에 수원 작물시험장에서 실시하였다. 유한신육형인 황금콩과 장엽콩, 무한신육형인 Clark와 Williams를 공시하여 신육형간의 생육과 수량형질의 차이를 구명한 바 그 주요결과를 요약하면 다음과 같다. 1. 무한신육형은 유한신육형보다 개화시로부터 정엽전개기까지의 일수가 평균 30일 더 길었으며 개화시 이후 주경절수도 7-8개 정도 더 증가되었다. 2. 유한신육형은 성숙기의 협실과 경의 건물중이 중하부에서 많았으며, 무한신육형은 중간부위에서 많았다. 3. 전 생육기간을 통하여 유한신육형이 무한신육형에 비하여 단립면적당 건립중이 높게 경과하였으나 무한신육형은 영양생장기간이 길고, 생육후기에 있어서 엽면적의 유특능력이 유한신육형보다 컸다. 4. 개체간 변이는 분지형질>주경과 개체전체의 생육 및 수량형질>주경의 형태적형질과 100립중의 순이었다. 5. 초기에 형성되는 생육형질보다는 후기에 성립되는 수량형질의 변이가 대체로 크게 나타났고, 무한신육형이 유한신육형보다 변이가 컸다. 6. 개체내 1립중의 변이계수가 유한신육형은 13.6-13.8%, 무한신육형은 18.5-21.1% 로서 유한신육형이 무한신육형보다 개체내 1립중의 변이가 작아 립의 평균일도가 높았다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1992년도 춘계 학술대회지
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• pp.76-77
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• 1992

• 한국작물학회지
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• 제36권1호
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• pp.57-64
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• 1991

식물생장조절제가 벼 기계이앙 어린모 육묘시 맷트형성에 미치는 효과를 검토하기 위하여 오합벼를 공시하여 8가지의 생장조절제를 사용, 종자침종하여 맷트형성 효과와 뿌리생장을 조사하여 다음과 같은 결과를 얻었다 1. Metalaxyl ( 25 % 수화제)은 어린모의 뿌리신장과 근모발생에 탁월한 효과가 있었으며 Tetra-cycle, Pachlobutrazol, NTN-821은 처리농도가 높을수록 초장과 근장이 짧아지고 간태가 굵어졌다. 2. Metalaxyl( 200, 1,000ppm) 처리는 무처리에 비하여 근수는 비슷하면서 뿌리신장과 근모발생이 현저히 증가되어 맷트형성이 아주 양호하였던 반면에 Tetracycle 처리에서는 근수는 증가되었지만 근장이 짧아져서 맷트형성이 불량하였다. 3. 공시약제 중 Metalaxyl의 맷트형성 촉진효과가 인정되었으며, 1,000ppm까지는 농도가 높을 수록 맷트형성이 좋아지는 경향이었으며, Metalaxyl의 종자침종을 위 한 적정온도는 약 200ppm으로서 실제로 이용할 때는 1, 000 배액으로 사용하면 되겠다. 4. Metalaxyl의 종자침종 처리로 어린모의 맷트형성은 무처리에 비하여 약 1～2일 단축시킬 수 있었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.120-120
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• 2022

Agrivoltaic System (AVS) was introduced with the concept that it could generate electricity by using the extra light remain after crops use for photosynthesis in farm, which can earn additional income. However, crop yield was declined under the AVS condition due to the decrease in light energy. In the past, many researchers have been studied about crop states under shading conditions. However, the phenomenon of partial shading such as under the AVS is not well studied. In this study, to figure out the response of crop under the different light conditions, the electron transport rate (ETR) and non-photochemical quenching (NPQ) of rice was investigated using the chlorophyll fluorescence measurement. Also, physiological changes of crops under the shading conditions were investigated. The growth experiment under partial shading under AVS and overall shading which made of 35% shade cloth was conducted to understand the eco-physiological responses of rice to light in terms of the photosynthesis. Under the shading conditions, SPAD value and chlorophyll contents were higher, but the leaf thickness was lower than control. The overall shading condition show lower ETR than others during the growing season. In contrast, NPQ was higher than other treatments. This means the available light energy cannot contribute to photosynthesis under the shading condition.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2006년도 한국약용작물학회 공동춘계학술발표회
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• pp.476-477
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• 2006

• 한국약용작물학회지
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• 제10권4호
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• pp.243-248
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• 2002

The effects of basal media, carbon, nitrogen, phosphate and some major macro elements on growth and shikonin production in Lithospermum erythrorhizon hairy root culture were studied. Among examined media, growth of hairy root cultured in B5 liquid medium was rapid, whereas shikonin production was high in MS liquid medium. Under B5 basal medium, sucrose concentration for optimal growth and shikonin production was 9% and 4% respectively. The growth and shikonin production on pH changes in B5 medium resulted little effect in pH 5.8 to pH 8.8 ranges, whereas growth was decreased dramatically in both above 8.8 and under 5.8. Nitrogen source and concentration effected on the growth and shikonin production. The highest growth rate was in B5 medium (50 mM $KNO_3$ and 1 mM $NaH_2PO_4)$, whereas the highest shikonin production was in the condition supplemented with 5 mM $KNO_3$ and 10 mM $NaH_2PO_4$.

• 한국작물학회지
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• 제51권4호
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• pp.303-309
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• 2006

The study examined the effects of $CO_2$ enrichment on growth of soybean (Glycine max). Two soybean varieties were used, Taekwang and Cheongja. The plants were grown in growth chambers with a 12-h photoperiod and a day/night temperature of $28/21^{\circ}C$ at the seedling stage and $30/23^{\circ}C$ from the flowering stage. The plants were exposed to the two elevated $CO_2$ levels of 500 and 700 ppm and the ambient level of 350 ppm. Results of the experiment showed that at the second-node trifoliate stage of the two varieties, the elevated $CO_2$ increased plant height, leaf area and dry weight. The elevated $CO_2$ also raised the photosynthetic rate of soybean as compared to the ambient level. From the beginning bloom stage to the full maturity stage of the two varieties, the elevated $CO_2$ increased plant height, leaf area, seed weight and photosynthetic rate. The stomatal conductance and transpiration rate decreased on long days relative to short days of treatment. Through the entire stages, the elevated $CO_2$ increased the water use efficiency of soybean plants because stomatal conductance and transpiration rate decreased at the elevated $CO_2$ levels relative to the ambient level.

• 한국작물학회지
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• 제66권4호
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• pp.375-382
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• 2021

For stable cultivation in double cropping, it is important to use potato (Solanum tuberosum L.) cultivars with a short dormancy period of 50-70 days and plant seed tubers of appropriate type and size. An experiment was conducted during 2018-2019 to investigate the effects of seed tuber type and size on growth and yield performance in double cropping. Whole tubers of three sizes (10-20 g, 30-40 g, and 50-60 g) and conventional cut tubers weighing 30-40 g from three cultivars with different dormancy periods, namely 'Daeji' (40-60 days), 'Eunsun' (50-60 days), and 'Saebong' (50-80 days), were planted, and their field performance was compared. Regardless of the cultivar, the increase in the whole tuber weight up to 30-40 g led to fast emergence, thereby increasing ground cover rate, shoot growth rate, and tuber growth rate, which ultimately improved tuber yield by 33-54%. Comparing the whole and cut tubers, 'Daeji' and 'Eunsun' showed similar growth and yield performance; as such, the performance of whole tubers weighing 10-20 g was comparable to that of cut tubers weighing 30-40 g. However, 'Saebong', a cultivar with relatively long dormancy period, performed better with cut tuber than with whole tubers. Based on these results, we recommend the use of whole tubers weighing over 30 g for double cropping. Further studies to break tuber dormancy are warranted in cultivars with relatively long dormancy periods (50-80 days), such as 'Saebong'.