• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.612-613
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• 2006

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.434-444
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• 2013

In order to evaluate drought risk at upland according to climate change scenario (RCP8.5), we have carried out the simulation using agricultural water balance estimation model, called AFKAE0.5, at 66 weather station sites in 2020, 2046, 2050, 2084, and 2090. Total Drought Risk Index between the first month (f) and last month (l) (TDRI(f/l)) and maximum continuous drought risk index (MCDRI(f/l)) were defined as the index for analyzing pattern and strength of drought simulated by the model. Based on distribution maps of MCDRI (1/12), drought strength was predicted to be most severe in 2084 for all regions. Some regions showed severe risk of drought meaning over 20 days of MCDRI (1/12) in the other years, while MCDRI (1/12) in other regions did not reach 5 days. Even though maximum value of TDRI (1/12) in 2090 was greater than in 2050, more severe drought risk in 2050 than in 2090 was predicted based on MCDRI (4/6). It implies that drought risk should be assessed for each crop with its own growing season.

• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.749-760
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• 2018

In Korea, the largest agricultural lands are paddy fields which have poor infiltration and drainage properties. Recently, the Korean government has pursued cultivating upland crops in paddy fields to reduce overproduced rice in Korea. For this policy to succeed, it is critical to understand the topographic information of paddy fields and its effects on upland crops cultivated in the soils of paddy fields. The objective of this study was to characterize the growth properties of sesame and perilla from paddy fields with three soil topographic features and soil water effects which were induced by the topographic features of the sesame and perilla. The crops were planted in paddy fields located in Miryang, Gyeongnam with different topographies: mountain foot slope, local valley and alluvial plain. Soil water contents and groundwater levels were measured every hour during the growing season. The paddy field of the mountain foot slope was significantly effective in alleviating wet injury for the sesame and perilla in the paddy fields. The paddy field of the mountain foot slope had a decreased average soil water content and groundwater level during cultivation. Stress day index (SDI) from the alluvial plain paddy field had the greatest values from both crops and the smallest from the ones from the paddy field of the mountain foot slope. This result means that sesame and perilla had the smallest stress from the soil water content of the paddy field on the mountain foot slope and the greatest stress from the soil water content of the alluvial plain. It is important to consider the topography of paddy fields to reduce wet injury and to increase crop yields.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.5
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• pp.369-382
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• 2017

Accurate and optimal water supply to cereal crop is critical in growing stalks and producing maximum yields. Recently, upland crops are cultivated in paddy field soils to reduce overproduced rice in Korea. In order to increase productivity of cereal crops in paddy fields which have poor percolation and drainage properties, it is necessary to fully understand crop response to excessive soil water condition and management of soil drainage system in paddy field. The objectives of this study were to investigate effects of excessive soil water to sesame growth and to quantify stress response using groundwater levels. Two cultivars of sesame were selected to investigate; Gunbak and Areum. These sesames were planted in paddy fields located in Miryang, Gyeongnam with different soil drainage levels and drainage systems. The experiment site was divided into two plots by drainage class; very poorly and somewhat poorly drained. Two different drainage systems were applied to alleviate excessive soil water in each plot: open ditch and pipe drainage system. Soil water contents and groundwater levels were measured every hour during growing season. Pipe drainage system was significantly effective to alleviate wet injury for sesame in paddy fields. Pipe drainage system decreased average soil moisture content and groundwater level during sesame cultivation. This resulted in greater yield and lignan contetns in sesame seeds than ones from open ditch system. Comparison between two cultivars, Gunbak had greater decrease in growth and yield by excessive soil water and high groundwater level than Areum. Seed components (lignan) showed decrease in seeds as soil water increased. When soil moisture content was greater than 40%, lignan content tended to decrease than ones from less soil moisture content. Based on these results, pipe drainage system would be more effective to reduce wet injury to sesame and increase lignan component in paddy field cultivation.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.445-451
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• 2013

We researched nitrogen and green manure yield of crotalaria by seeding rate; 50, 60, 70, 80, 90 kg $ha^{-1}$ in upland soil to find out crotalaria's optimal seeding rate. Crotalaria's plant height and number of leaves increased when the harvest time was later regardless of its seeding rate. Its nitrogen content of above-ground part was 19.8 g $ha^{-1}$, and C/N ratio was 22.5. The highest nitrogen content (50.3 g $ha^{-1}$) was found in flowers part, followed by its leaves, roots and stems. The green manure yields of crotalaria increased when the harvest time was later. The green manure yield of crotalaria was biggest in 50kg $ha^{-1}$ which was low in seeding rate. It tended to decrease when the seeding rate was higher, and the nitrogen yield had the same tendency. Therefore, the appropriate seeding rate was 50kg $ha^{-1}$ and the time for application to soil was considered to be the flowering stage.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.287-290
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• 2003

To devise better development plan, survey was conducted about current Farmer's irrigation Practice on upland in the Youngsan River Irrigation Project District IV. Major upland crops are garlic and onion in this region. Currently, upland irrigation is conducted using ground water. It is found that irrigation interval is $2{\sim}3$ day for dry-field rice and $3{\sim}7$ days for other crop, in general. Whole day is required to irrigate for many farmers due to lack of facilities and water source. Farmers have no intention to change staple crops even after completion of Irrigation Project of Youngsan River District IV.

• 한국약용작물학회:학술대회논문집
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• 2007.05a
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• pp.72-73
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• 2007

• 한국약용작물학회:학술대회논문집
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• 2012.05a
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• pp.217-218
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• 2012

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.5
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• pp.558-562
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• 1996

The growth and yield of Job's tears (Coix lacryma-jobi L.) under the flooded paddy and upland (dry paddy) field conditions were compared at three sowing dates and two planting densities. Job's tears grown under flooded paddy field was much shorter in plant height, but greater in number of tillers than those grown under upland. Photosynthesis rate of Job's tears grown under flooded paddy field was higher and the weight of dry roots heavier but the damages of pest and leaf blight disease smaller than those grown under upland. For the above mentioned reasons, the grain yield of Job's tears grown under flooded paddy field was higher by up to 85% than that grown under upland. There was no significant difference in grain yield between the planting densities. The earlier sowing brought about the less grain yield in upland field condition, while sowing plot on the 15th of May showed the highest grain yield in the flooded paddy field condition.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.6
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• pp.677-682
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• 2015

Although it is not a landscape crop according to MIFAFF(ministry of agriculture, food and rural affairs), yellow mustard is considered a superb landscape crop because of its growth and flower characteristics. We sowed yellow mustard as a landscape and green manure crop in upland soil (four types of soil texture) in spring. And we studied its flowering characteristics, dry weight, and nitrogen yield. The growths of yellow mustard were possible in every soil ranging from sandy soil to clay loam. Its height was 54.1 ~ 76.1cm and the number of node per hill was 11.3 ~ 17.0. Its flowers had a light yellow. It took about 44 ~ 50 days to flower, and flowered for 22~25 days. The dry weight of yellow mustard was $2.27{\sim}3.60tonha^{-1}$ with highest in sandy loam and loam. Among the nutrients of yellow mustard, nitrogen(T-N) was $12.6{\sim}20.8gkg^{-1}$, and C/N ratio was 21.6~37.7. The nitrogen yield of yellow mustard was $35{\sim}62kgha^{-1}$. In conclusion, because of its flowering characteristics and dry weight, yellow mustard was considered appropriate for both green manure and landscape crop uses.