풋고추 플러그 육묘시에 칼리의 최적 시비농도를 구명하기 위하여 32구 플러그 트레이에 TK2를 채운 다음 종자를 파종하여 칼리를 농도별로 처리하여 식물체의 생육과 광합성에 미치는 효과를 조사하였다. 초장, 줄기 직경, 엽면적 및 총 건물중은 K의 농도가증가할수록 생육이 촉진되었으며, ‘녹광’ 보다는 ‘꽈리’의 생육이 더 좋았다 품종과 K의 농도에 따라서 엽록소의 함량은 차이가 있었는데, ‘녹광’은 K의 농도가 2.0배까지 높을수록 증가하였으나 ‘꽈리’는 1.0배 이상의 농도에서는 차이가 거의 없었다 순광합성율은 ‘녹광’의 경우에는 1.5배의 농도에서 ‘꽈리’의 경우에는 2.0배의 고농도에서 가장 높았으며, 기공전도도와 수분증발율도 순광합성율과 비슷한 경향이었다.

‘서명’은 서남부 간척지적응성 고품질 벼품종육성을 목적 으로 2000/2001년 동계에 국립식량과학원 벼맥류부에서 간 척지적응성 우량계통인 계화21호를 모본으로 하고 단간, 내 도복 복합내병성인 ‘밀양165호’를 부본으로 인공교배하였다. F3 이후부터는 계통육종법에 의하여 육성 선발하여 2005년부 터 2006년까지 생산력검정을 실시한 결과 고품질, 내도복, 내 병성인 HR22240-29-5-3-3 계통을 계화30호로 계통명을 부 여하였다. 2007년부터 2009년까지 지역적응시험을 실시한 결과 서남부 간척지에 적응성이 높고 내도복성이며 미질이 우수한 계통으로 인정되어 2009년 12월 농촌진흥청의 농작 물 직무육성 신품종 선정심의회에서 ‘서명’으로 명명하였다. 서명은 남서해안지 및 호남·영남평야지의 보통기재배에서 평 균 출수기는 8월 14일로 ‘남평벼’보다 2일 빠른 중만생종이 다. 간장은 70 cm, 주당수수는 12개, 수당립수는 87개이며 등숙률은 93.0%, 현미 천립중이 22.8 g인 단립종이다. 도열 병 밭못자리 검정에서 강한 반응을 보였고 내구저항성도 강 한 품종이며 깨씨무늬병과 줄무늬잎마름병에 저항성이나 기 타 바이러스병 및 흰잎마름병, 해충에는 약한 품종이다. 내냉 성 검정에서 유묘적고, 출수지연, 임실률은 남평벼와 비슷했 고, 수발아율은 36%로 ‘남평벼’ 보다 높은 편이며 도복에 강 한 반응을 보였다. 쌀 외관은 심복백이 없이 맑고 투명하며 식미와 관련된 단백질함량 및 아밀로스함량은 각각 7.2% 및 19.3%였고, 밥맛 관능검정에서는 0.06으로 경기도산 추청벼 0.17보다 낮았다. 도정특성 중 제현율과 도정률, 완전미도정 수율은 남평벼보다 높았고 백미완전립률은 97.2%로 ‘남평벼’ 98.2% 보다 낮았다. 쌀 수량은 보통기 보비재배에서 중서부지 에서는 5.6 MT/ha로 ‘화성벼’ 대비 10%가 증수되었고 남서 부해안지에서 5.5 MT/ha, 영남평야지에서 5.6 MT/ha로 ‘남평 벼’ 대비 1-2% 증수하였으며 호남평야지에서는 5.7 MT/ha로 ‘남평벼’ 대비 99% 수준이었다. 3년 평균 쌀 수량은 5.6 MT/ha 로 대비품종과 비슷하였다.

The time of panicle initiation change by transplanting date, and this change is affected by heading ecotype and seedling age. So we assessed the variations of panicle initiation, spikelet differentiation and heading date affected by transplanting dates, rice cultivars and seedling ages. And we compared the growth durations and meterological factors between chief growth stages. The differences of growth duration from transplanting date to spikelet differentiation by seedling age were 1~3 days in all transplanting of Unkwang, but it increased to 4 days in Hwayeong transplanting on May 1 and June 30, and Nampyeong transplanting on June 30. The growth durations from panicle initiation to heading of Unkwang and Hwayeong increased until transplanting time by May 31, and decreased thereafter. The growth durations of Nampyeong increased in transplanting on May 16 and May 31. In each transplanting, mean temperature of 30 days after heading was highest in early transplanting, but sunshine hours in the period were highest in transplanting on June 30 in Unkwang, in transplanting on June 15 in Hwayeong, and higher in transplanting on May 31 and June 15 in Nampyeong. The growth duration between spikelet differentiation and heading showed variation according to rice cultivars and transplanting date, Those were 22~26 days in Unkwang, 21~27 days in Hwayeong and 21~28 days in Nampyeong.

A field study was conducted to understand nitrogen use efficiency of high yielding Japonica rice varieties under three levels of nitrogen fertilizer (90, 150 and 210 kg N ha -1 ) in Iksan, Korea. Two high yielding rice varieties, Boramchan and Deuraechan, and an control variety, Dongjin2, were grown in fine silty paddy. Nitrogen use efficiencies (NUE) were 83.3, 56.3, and 41.2 in 90, 150, and 210 kg N ha -1 fertilizer level, respectively. Total nitrogen uptake varied significantly among nitrogen levels and varieties. Variety Dongjin2 showed the highest nitrogen uptake efficiency (NUpE), while Boramchan and Deuraechan showed higher nitrogen utilization efficiency (NUtE). However, Nitrogen harvest index (NHI) was higher in Boramchan (0.58) than Deuraechan (0.57) and Dongjin2 (0.53). Rough rice yield showed linear relationship with total nitrogen uptake (R 2 =0.72) within the range of nitrogen treatments. Boramchan produced significantly higher rough rice yield (8546 kg ha -1 ) which mainly due to higher number of panicles per m 2 compared to Deuraechan (7714 kg ha -1 ). Deuraechan showed higher number of spikelets per panicle, but showed lower yield due to lower number of panicle per m 2 . Rice varieties showed different nitrogen uptake ability and NUE at different nitrogen level. Plant breeders and agronomist should take advantage of the significant variations and relationships among grain yield, NUpE, and NUE.

This study was performed at Rice and Winter Cereal Crops Department of NICS during 2007 and 2008 to investigate the characteristics of rice leaf emergence and to obtain basic data which can be used for rice growth simulation model by which we can forecast rice growth stage and heading date accurately under different cultivars, transplanting date, and climatic conditions. To confirm leaf emergence rate according to rice maturing ecotype, we surveyed the leaf emergence rate and heading date of Unkwangbyeo, Hwayoungbyeo and Nampyeongbyeo which are early maturing, medium maturing and medium-late maturing cultivars, respectively, according to seedling raising duration and transplanting time. When seedling duration was 15 days, the growth duration between transplanting time and completion of flag leaf emergence on main culm were 51.5~78.3 days in Unkwangbyeo, 55.3~87.9 days in Hwayoungbyeo and 58.4~98.4 days in Nampyeongbyeo, respectively. When seedling duration was 30 days, they were 50.1~75.5 days in Unkwangbyeo, 52.4~84.7 days in Hwayoungbyeo and 56.4~93.8 days in Nampyeongbyeo, respectively. As transplanting time delayed, the emerged leaf number after transplanting decreased in all rice cultivars. The cumulative temperature between transplanting time to completion of flag leaf elongation on main culm were 1,281~circC~1,650~circC in Unkwangbyeo, 1,344~circC~1,891~circC in Hwayoungbyeo and 1,454~circC~2,173~circC in Nampyeongbyeo, respectively. Leaf emergence rate on main culm were precisely represented by equation, y = y0 + a / [1 + exp( - (x - x0 ) / b)]c, when we used daily mean temperature as variable.

This study was carried out to confirm the effects of climate change to growth, yield and quality of rice by the global warming. By the study of Korea Meteorology Administration, the temperature of Korea increased 0.95℃ during last 34 years and the width of temperature increase be on an increasing trend gradually. As temperature increases, rice is faced with critical change such as growth duration shortening, heading acceleration, yield decrease and quality deterioration. So, we studied the rice growth and yield change by the temperature increase. To confirm the effects of temperature increase, rice cultivars such as early maturing Unkwangbyeo, medium maturing Hwayoungbyeo and late maturing Nampyeongbyeo were transplanted on 1, 15, 30 of June inner transparent vinyl house which was treated by different temperature. The increased mean temperature were 1.4℃～3.5℃, respectively, compared to outer field. The growth duration from transplanting to heading were shortened by the temperature increase. In June 1 transplanting, especially the growth duration of early maturing Unkwangbyeo was shortened greatly by temperature increase. As temperature increases, rice yield decreased in most cases. In 1.4℃ temperature increase, rice yield of June 15 transplanting were higher than those of other transplanting, but in 2.1℃ or more temperature increase, the rice yield of June 30 transplanting were similar or more than those of other transplanting.

To select rice cultivars adaptable to low fertilization in puddled soil drill seeding, 20 rice cultivars were tested in Iksan. The seedling stand ratio of Kwanganbyeo, Junganbyeo, Saegyehwabyeo, Pyeonganbyeo were higher than 80%, but those of Hwalangbyeo, Hoanbyeo were lower than 60%. The tiller number per m2 was 4% smaller in low fertilization compared to conventional fertilization level. In low fertilization, the decrease rate of tiller number per m2 were less than 1～2% in Ansanbyeo, Juan 1, Geumanbyeo and Hoanbyeo, but more than 6～9% in Junganbyeo, Hwaanbyeo, Daesanbyeo and Saegyehwabyeo. Harvest index was 2.8% higher in low fertilization compared to conventional fertilization level. Nonganbyeo, Hopumbyeo, Dongjin 2 and Saegyehwabyeo showed high harvest index, but Gwanganbyeo, Geumanbyeo and Hwalangbyeo showed low harvest index. In low fertilization, milled rice protein content were lower than 6.0% in 14 rice cultivars including Juanbyeo and Kwanganbyeo, but 6.1～6.4% in other rice cultivars. Rice yield decreased 6% in low fertilization compared to conventional fertilization. Rice yield decrease were smaller as 2～3% in Hoanbyeo, Juanbyeo, Kwanganbyeo, Chengdambyeo, Geumanbyeo and Donganbyeo, but bigger as 7～8% in Nonganbyeo, Nonghobyeo. Dongjin 2, Saegyehwabyeo and Ansanbyeo. Owing to 2.4% increase of head rice ratio in low fertilization compared to conventional fertilization, head rice yield decreased 4% in low fertilization. Cultivating rice in puddled soil drill seeding with low fertilization, the rice cultivars such as Kwanganbyeo, Hopumbyeo, Pyeonganbyeo and Dong 2 showed lower than 6.0% milled rice protein content and more than 470㎏/10a milled rice yield.

This study was conducted to investigate the variation of rice quality and the effect of labor-saving by using slow-releasing fertilizer when doing direct drill seeding on flooded paddy surface by large scale direct drill seeding machine in Honam plain area. The results obtained by changing the amount of slow-releasing fertilizer in 2008, 2009 are as follows. Considering rice growth, head rice yield and rice quality, the optimum amount of slow-releasing fertilizer was 7kg/10a, when doing direct drill seeding on flooded paddy surface in southern plain area of Korea. When using slow-releasing fertilizer 7kg/10a, the protein content became lower, and head rice ratio became higher than that of conventional nitrogen split application method as basal fertilization, top dressing at tillering stage, fertilization at panicle initiation stage.

This study was conducted to select suitable rice cultivars for high-quality rice production in silage barley-rice double cropping in Honam plain area by National Institute of Crop Science from 2008 to 2009. Heading dates of all tested cultivars were before the safe heading limit(Aug. 31). Rice yield was superior in "Keunseom", "Hanareum", "Hanmaeum", "Onnuri", "Hopum", "Juan 1", "Dongjin 1", and was little in "Daepyeong", "Hwasin", "Malgeumi", "Chilbo", "Nampyeong", "Hopyeong". Protein content was high in "Hanareum", "Keunseom", "Chilbo", "Nampyeong", and was low in "Hanmaeum", "Dami", "Sindongjin", "Pyeongan", "Samgwang". And head rice ratio was high in "Malgeumi", "Hwanggeumnuri", "Samgwang", and was low in "Keunseom", "Hanareum", "Dami", "Hanmaeum", "Hwasin". In consideration of all the factors, in conclusion, proper cultivars for silage barley-rice double cropping are "Onnuri", "Hwanggeumnuri", "Hopum", "Dongjin 1", "Juan 1".

This study was carried out to investigate the proper interval of water exchange according to nitrogen fertilizer level at medium saline soil which are 0.3 or more soil salinity in southwestern reclaimed saline land. The nitrogen fertilizer level were 14, 17, 20kg per 10a, and the interval of water exchange were every 3, 6, 9 days after transplanting. The summarized experimental results are as follows. The salinity were maintained as low when the interval of water exchange were every 3 or 6 days after transplanting, but salinity was highest at rooting stage, and decreased from that, so salinity were about 0.3 at panicle initiation stage or ripening stage when the interval of water exchange was every 9 days after transplanting. The rice yield were 537-552kg/10a when the interval of water exchange was every 3 days with 17-20kg/10a nitrogen fertilizer level, and 519-533kg/10a when the interval of water exchange was every 6 days with 17-20kg/10a nitrogen fertilizer level, but decreased outstandingly in the other treatments. Considering the yield and salt injury at medium saline soil at southwestern reclaimed saline land, proper nitrogen fertilizer level was 17-20kg/10a when the interval of water exchange were every 3 or 6 days after transplanting.

This study was carried out to investigate the optimum application time of basal fertilization in direct-seeded rice on flooded paddy surface at medium saline soil in southwestern reclaimed saline area which is Munpo series and have 0.3 or more soil salinity. The nitrogen fertilizer level were 14, 17, 20kg per 10a, and the basal fertilization were applied before sowing, 10, 20, 30 days after sowing along with topdressing at tillering stage, respectively. The summarized experimental results are as follows. Seedling stand was proper when basal fertilization was applied before sowing, but lower than appropriate seedling stand when basal fertilization were applied 10, 20, 30 days after sowing along with topdressing at tillering stage. The rice yield were 509-541kg/10a when 14-20kg/10a basal fertilization was applied before sowing, and 368-481kg/10a when basal fertilization were applied 10, 20, 30 days after sowing along with topdressing at tillering stage. Considering the yield and salt injury at medium saline soil in southwestern reclaimed saline area, the application of basal fertilization before sowing was superior for improving seedling stand, and 14-20kg/10a fertilization rate was allowable.

Surface sediments and seawater were sampled at Masan and Haengam Bays of Korea, to evaluate contamination by sewage-derived organic matter using fecal sterols. Six stream-water samples into Masan and Haengam Bays were also sampled. Total concentrations of eight sterols (coprostanol, epichloestanol, epicoprostanol, cholesterol, cholestanol, brassicasterol, stigmasterol and β-sitosterol) were in the range of 1,274～4,768 ㎍/g dry weight in suspended particulate from the stream-water, 292～2,244 ㎍/g dry weight in suspended particulate from the seawater and 4.5～27.2 ㎍/g dry weight in the sediments. Although sterol compositions in sediments, seawater and stream-water were different, cholesterol was the predominant sterol in all samples. The proportion and concentration of coprostanol, a sewage tracer, in stream-water was much higher than those in sediment and seawater. The sterol levels including coprostanol in the sediments and seawater were higher at inner basin than at the outer bay. Some molecular indices and multivariate statistical analysis were used to assess the origin of these sterols and sewage contamination in the study area. The sterol composition patterns in stream-water were mainly associated with contamination by sewage-derived organic matters and those of seawater were associated with the activities of marine-originated organisms. Sterol levels in the sediments were both from the sewage input through stream-water and the marine- originated organisms. This survey suggests that the main source/route of sewage-derived organic matters in Masan Bay is the input of stream-water into the bay.