• 한국농림기상학회지
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• 제5권3호
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• pp.191-199
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• 2003

Optimum transplanting time for extremely early rice cultivation as an after-crop of fruit and vegetables under greenhouse conditions in the southern area was determined. Rice was transplanted on March 10, March 20, March 30, April 10 and April 20 far three years from 1998 to 2000. Meteorological computations for rice production were high for heading between early May and early July, but they were too low for heading between late July and early August. Especially the expected yield predicted with 35,000 spikelets, the average spikelets per $m^2$ for extremely early transplanting. Computation for heading between late July and early August was low by 106 kg/10a compared with that yield at heading during the same period in the field. As the transplanting date in extremely early rice cultivation was earlier) rice growth at early stages was more retarded by low temperature. Rice growth at heading stage recovered with high temperature, showing less difference for the transplanting date. Abnormal tillers occurred by 15.5∼22.2%. The contribution of 1,000 grain weight${\times}$ripened grain ratio to yield of the extremely early rice cultivation in the greenhouse was 50.6%, indicating 16% hi일or than the degree of panicle per $m^2$ on yield. The estimated optimum transplanting time on the basis of yield for the extremely early greenhouse rice cultivation ranged from March 19 to April 28, and the estimated critical transplanting date on the basis of accumulated effective temperature was March 12. Rice reduced the amount of NO$_3$-N by 97.1% and EC by 90.5% in greenhouse soil with continuous fruit/vegetables fer more than a 10-year period, and completely removed the root-knot nematodes.

• 한국농공학회지
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• 제31권1호
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• pp.31-44
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• 1989

In the vinyl house cultivation, the water consumption, evapotnanspirafion ratio, growth condifion by the growing stages and yields of tomato and cucumber were investigated when they cultivated by nutriculture, rice hull charcoal culture and NFF culture. The results obtained are summarized as follows: 1. The mean air temperature in the vinyl house during the experimental perica j was 1.9$^{\circ}$C higher than the outdoor air temperature, the rrnocirnum and minimum air temperature in the vinyl house was 4.6C and 1.7$^{\circ}$C higher than the outdoor temperature, respectively, and the mean daily evaporation in the vinyl house during the experimental period was 4.3rnm that is 02rnrn more than the outdoor evaporation 2. In the tomato cultivation, the growth of rice hull charcoal culture was the best among the three methods, and the growth of NFT culture and nutriculture were worse than the soil cultivation which is standard, and among the nutriculture, the growth of EC 1.3m.mho plot was the best. 3. In the cucumber cultivation, the growth of rice hull charcoal culture was the best, and while the growth condition of NFT culture was worse than the standard soil cultivation, the growth of nutriculture was better than the standard soil cultivation, and the growth of EC 1.3m.mho plot was the highest among the different treatments in the nutriculture. 4. In the tomato cultivation, the total water consumption of rice hull charcoal culture plot was 1107.5rnm which is the highest amount among the three methods, and in the nutriculture, the total water consumption of EC 1.3m.mho plot was 22lAmm which is the highest among the three different treatments. 5. In the cucumber cultivation, the total water consumption of rice hull charcoal culture was 11762rnm which is the highest, and the total water consumption of EC 1.3m.mho plot was 284.9rnm which is more than the 278.9mm of EC 1.Smmho plot and 262.9mm of EC 1.7rnmho plot. 6. The crop coefficient(Kc) of tomato was 0.82 in NFT culture, 4.67 in rice hull charcoar culture and 0.86~0.91 in nutriculture. 7. The crop coefficient(Kc) of cucumber was higher than tomato as 1.13 in NFT culture, 520 in rice hull charcoal culture and 1.08~1.19 in nutriculture. 8. The evapotranspiration ratio in the mid and late season were higher than the beginning and elongation stage, and the average evaportranspiration ratio of tomato and cucumber was 3.81 and 424, respectively, in the rice hull charcoal culture plot. 9. In the tomato cultivation, the total yield per plant of rice bull charcoal culture was 1443.Og which is the highest, and in the nutriculture, their yields were worse because of the damage of downy nidew disease. 10. In the cucumber cultivation, the total yield per plant of rice hull charcoal culture was 1965.7g which is the highest, and while the yield of NFT culture was ahout 25% lower than the stadard soil cultivation, the yield of nutriculture was higher than the standard soil cultivation, and among the treatments in the nutriculture, the yield of EC 1.3m.mho plot was the highest.

• 한국토양비료학회지
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• 제49권4호
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• pp.335-340
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• 2016

Soil organic carbon plays an important role on soil physico-chemical properties and crop yields in paddy soil. However, there is little information on the soil organic carbon under different forage cultivation during winter season in rice paddy. In this study, we investigated the soil organic carbon and physico-chemical properties in 87 fields of paddy soil cultivated with Barley, rye, and Italian ryegrass (IRG) as animal feedstock during winter season. Organic carbon was 12.9, 14.3, and $16.9g\;C\;kg^{-1}$ in soil with barley, rye, and IRG cultivation, respectively. Among rice-forage cultivation systems, the rice+IRG cropping system was 19.5% higher than in the mono-rice cultivation. Bulk density ranged from 1.17 to $1.28g\;cm^{-3}$ irrespective of cropping systems, and had strongly negative correlation with the soil organic carbon in the rice+IRG cropping system. Carbon storage in rice+IRG cropping systems was average $29.6Mg\;ha^{-1}$ at 15 cm of soil depth, which was 20.4 and 10.3% higher than those of barley and rye cultivation. Increasing carbon storage in paddy soil contributed to the fertility for following rice cultivation. This results indicated that IRG cultivation during winter season could be an alternative and promising way to enhance soil organic carbon content and fertility of paddy soil.

• 수완나부미
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• 제9권2호
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• pp.91-122
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• 2017

Before the start of the North Borneo Company administration in North Borneo (now Sabah, Malaysia) in 1882, the Timugon Murut of today's interior Tenom District lived in longhouses, and practiced head-hunting during wars with other Murutic ethnic groups. Their economy revolved around swidden agriculture of hill rice, sago, and cassava. Wet rice cultivation and water buffaloes were introduced just before 1885. Wet rice was planted on the alluvial plains around the Pegalan and Padas Rivers, while dry rice was planted on hillside swiddens that had been cleared by slash-and-burn methods. Today, wet rice cultivation and cash-cropping on the plains are the main Timugon socioeconomic activities, while some families also plant dry rice on the hills as a back-up. The Timugon believe that the physical world is surrounded by the spiritual world, and everything was made by the creator Aki Kapuuno'. The focus of this field research paper is on the beliefs and ritual practices of the Timugon connected to their traditional rice agriculture. This study found that for generations, the Timugon believed that since animals were created by Aki Kapuuno' for the wellbeing of humans, various types of animals and birds convey omens to guide people. Thus, the older Timugon rice cultivation is strongly influenced by good and bad omens and taboos, and also involves symbolic practices and ritual offerings to guardian spirits of the rice. After the 1930s and especially since the 1960s, most Timugon became Roman Catholic Christians. Hence, this paper also examines changes in the traditional Timugon rice cultivation related beliefs and practices due to religious conversion and other factors.

• 농촌계획
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• 제20권4호
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• pp.35-43
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• 2014

The purpose of this study is to analyze emergy flows of rice for evaluating the value of rice production and sustainability. Emergy analysis evaluates the sustainability of systems or processes considering all the inputs to make a product or a sevice. In this study, we analyzed the emergy flows and indices of rice productionand compared the regional emergy values using statisticcal analysis: input materials, hours per unit area(10a), and production costs. As the results, we found that the rates of external investment (EIR= 18.87) and environmental loading (ELR=21.7) are significantly high during the rice cultivation. However, emergy yield ratio(EYR) shows that rice is a valuable resource because EYR is 5.12 and environmental Sustainability IndexSI value is as low as 0.24 and it shows rice has low sustainability. This study also shows that Chungcheongnam-do has the highest SI value for rice production due to low environmental loading and abundant natural energy during rice cultivation. These results of rice emergy flows and sustainability assessments could provide a way of sustainable rice cultivation with decrease of environmental loading from fertilizer.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.123-123
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• 2022

In order to evaluate the effect of nitrogen application levels on yield and protein content of rice varieties, a field experiment was conducted at National Institute of Crop Science of Korea in 2020. Five levels(0, 3, 5, 7, and 9 kg·10a^-1) of nitrogen fertilizer were treated to six Korean rice varieties. The nitrogen uptake amount, soil nitrogen content before and after rice cultivation, milled rice yield, and protein content in head rice were analyzed. As the treatment of nitrogen fertilizer increased, the nitrogen uptake amount of plants increased significantly. However, changes in nitrogen content in the soil before and after rice cultivation were different for each cultivar. The amount of nitrogen change in the soil decreased as the amount of nitrogen application increased in the three cultivars of Haepum, Gopum, and Odae, and the other three cultivars showed the opposite trend. As a result of correlation analysis of nitrogen application amount, nitrogen uptake amount, milled rice yield, and protein content of head rice, the five varieties except for Haepum showed a high correlation between these factors. The amount of nitrogen application and nitrogen uptake of plant showed a positive correlation about the milled rice yield and protein content of head rice. In particular, the protein content in head rice appeared to be more affected by nitrogen uptake amount than nitrogen application amount. As a result of this study, the yield and protein content of rice had positive correlations with the level of nitrogen fertilizer, and had a high correlation with the nitrogen absorption of plants.

• 한국토양비료학회지
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• 제49권6호
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• pp.662-668
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• 2016

No-tillage dry-seeding of rice can offer potential benefits by reducing time and labor cost compared with conventional tillage practices. This study was conducted to investigate the effects of no-tillage dry-seeding on rice growth and soil hardness in comparison with other rice cultivation methods, machine transplanting and wet-hill-seeding on puddled paddy. The seedling stand fell within optimum range for both no-till dry-seeding and wet-hill-seeding on puddled paddy. Plant height, number of tillers and SPAD values in no-tillage dry-seeding cultivation were higher than those observed in other methods. There were no significant differences in grain yield of rice among three cultivation methods. The quality characteristics of milled rice grown in no-tillage dry-seeding were similar to those grown in other cultivation methods. Soil hardness in top 10 cm depth was significantly higher in no-tillage dry-seeding than other cultivation methods, while soil hardness below 10 cm depth was highest in machine transplanting cultivation. Results indicate that no-tillage dry-seeding practice is comparable to conventional tillage system in terms of seedling establishment, growth, yield and grain quality.

• Mycobiology
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• 제46권3호
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• pp.283-286
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• 2018

Fusarium graminearum causes the devastating plant disease Fusarium head blight and produces mycotoxins on small cultivated grains. To investigate the timeframe of F. graminearum infection during rice cultivation, a spore suspension of F. graminearum was applied to the rice cultivars Dongjin 1 and Nampyeongbyeo before and after the heading stage. The disease incidence rate was the highest (50%) directly after heading, when the greatest number of flowers were present, while only 10% of the rice infected 30 days after heading showed symptoms. To understand the mechanism of infection, an F. graminearum strain expressing green fluorescent protein (GFP) was inoculated, and the resulting infections were visually examined. Spores were found in all areas between the glume and inner seed, with the largest amount of GFP detected in the aleurone layer. When the inner part of the rice seed was infected, the pathogen was mainly observed in the embryo. These results suggest that F. graminearum migrates from the anthers to the ovaries and into the seeds during the flowering stage of rice. This study will contribute to uncovering the infection process of this pathogen in rice.

• 한국토양비료학회지
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• 제48권4호
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• pp.271-277
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• 2015

Anaerobic decomposition of organic material in flooded rice fields produces methane, which escapes to the atmosphere primarily by transport through the rice plants. The annual amount of $CH_4$ emitted from a given area of rice is a function of the number and duration of crops grown, water regimes before and during cultivation period, and organic and inorganic soil amendments. Soil type, temperature, and rice cultivar also affect $CH_4$ emissions. The field experiment was conducted for three years to develop methane emission factor for water regime before the cultivation period from the rice fields. It was treated with three different water regimes prior to rice cultivation, namely: non-flooded pre-season < 180 days, non-flooded pre-season > 180 days, flooded per-season in which the minimum flooding interval is set to 30 days. Methane emission increased with days after transplanting and soil redox potential (Eh) decreased rapidly after flooding during the rice cultivation. The average methane emission fluxes were $5.47kg\;CH_4\;ha^{-1}day^{-1}$in flooded pre-season > 30 days, 5.04 in non-flooded pre-season < 180 days and 4.62 in non-flooded pre-season > 180. Methane emission flux was highly correlated with soil temperature and soil Eh. Rice yields showed no difference among treatments with water regime before the cultivation period.

• 한국작물학회지
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• 제48권6호
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• pp.534-539
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• 2003

이앙기 및 수확시기에 따른 쌀 품질을 식미 관점에서 검토하여 고품질 쌀 생산을 위한 기초 자료를 얻고자 2001년 서진벼, 일품벼, 추청벼를 공시하여 인천광역시 서구 경서동에 위치한 농업기반공사 김포간척지에서 실험한 결과는 다음과 같다. 1. 현미수량은 이앙시기간 고도로 유의한 차이가 있어서 3품종 모두 조기, 보통기재배가 만기재배보다 수량이 유의하게 많았다. 2. 백미의 단백질 함량은 이앙기와 수확시기간 고도의 상호작용이 있어서 발의 단백질 함량이 저하되는 수확시기는 이앙기에 따라 달랐다. 3. 이앙기에 따른 식미값은 서진벼와 일품벼는 조기와 만기재배에서 유의하게 높으나 추청벼는 만기재배에서도 떨어지지 않는 경향이었다. 4. 백미의 식미치는 등숙적산기온과 고도로 유의한 부의 상관(-0.43$^{**}$ )이 있어서 적산기온이 높을수록 식미치가 저하하였다. 5. 수량과 품질을 동시에 고려할때 조기 또는 보통기재배를 하되 수확시기는 출수후 40일로 다소 빠르게 하는 것이 유리한 것으로 판단되었다.