하천변 농경지에서 질소 시비량 차이가 옥수수 생육 및 수량에 미치는 영향

임정택,장재혁,노예진,류진희,정덕영,조진웅 韓國作物學會 2014 한국작물학회지 Vol.59 No.1

본 연구는 하천변 농경지에서 질소시비수준에 따른 옥수수의 생육특성과 수량성을 살펴보고 광합성 측정과 성분 분석을 통해 질소가 미치는 영향을 구명하여 하천변 농경지재배에서 질소 시비의 필요성과 적정 질소 시비를 통한 수량 증대의 가능성을 검토하기 위하여 수행하였다. 질소 처리에 따른 옥수수 생육특성은 초장과 착수고의 경우 질소시비량에 의한 큰 차이가 없었다. 광합성은 질소 시비량이 증가할수록 증가하여 36 kg 처리구에서 가장 높았다. 옥수수의 NDF와 ADF 함량은 처리구간 차이 없었으며 NDF는 출웅 후 8일 이후 감소하였으며, ADF는 출웅 후 15일 이후 감소하였다. 옥수수 잎의 질소 흡수량은 출웅기에 36 kg 처리구에서 가장 높았다. 수량 및 수량구성요소는 이삭길이와 100립중의 경우 처리구간 유의차가 없었으나 이삭직경과 립수의 경우 무처리구와 9 kg 처리구에 비하여 18 kg 처리구와 36 kg 처리구에서 증가하였고, 과피는 18 kg 처리구와 36 kg 처리구에 비하여 무처리구와 9 kg 처리구에서 두꺼웠고, 수량은 무처리구에 비하여 18 kg 처리구, 36 kg 처리구, 9 kg 처리구가 많았다. 옥수수 종실의 전분함량은 처리구간 유의차가 없었으며, 총당은 18 kg 처리구가 가장 높았고 아밀로펙틴은 18 kg 처리구에서 가장 높았으나 아밀로오스는 18 kg 처리구에서 가장 낮아 18 kg 처리구에서 찰성이 가장 강하였다. 이상의 결과로 하천변 농경지에서 옥수수 재배시 질소시비가 필요하며 가장 이상적인 질소 시비량은 10a당 18kg 정도로 판단된다. This study was conducted to investigate the effect of nitrogen rates on the growth characteristics and yield of maize in agricultural fields with the stream. This indicates the necessity and optimal level of nitrous fertilization to examine the possibilities of quantity enhancement. Plant height and ear height of maize were not significantly different among the nitrogen rates. Stem diameter and leaf area index increased in the nitrogen treatment compared to untreated control. Changes of photosynthetic rate in maize leaves depending on nitrogen treatments increased as much as nitrogen rates were increased up to the highest level, 36 kg per 10a. NDF and ADF content levels of maize were investigated with different nitrogen rates regardless of treatments. In the case of NDF, it showed a tendency to decrease after 8 days of tasseling date. ADF had also decreased after 15 days of tasseling date. Nitrogen uptake of maize leaves with different nitrogen rates showed the highest level, 4.9 g kg-1 with 36 kg per 10a on the tasseling date. Ear length and 100-kernel weight, there were no significant differences according to yield and the components with different nitrogen rates. Ear diameter and kernel number, nitrogen rates of 18 kg and 36 kg were increased compared to nitrogen rate of 9 kg per 10a and untreated control. The pericarps in 9 kg nitrogen rate and control were thicker than those of 18 kg and 36 kg treatment. The yield, 18 kg, 36 kg, and 9 kg treatments were increased by 10.96%, 9.27%, and 3.31%, compared to control. The component analysis on maize kernel with different nitrogen rates, starch showed no significant differences among treatments. Total sugar in 18 kg nitrogen treatment represented the highest content level, 6.37%. In addition, Amylopectin in 18 kg treatment showed the highest content level of 90.38%. However, amylose in 18 kg treatment showed the lowest level, 9.62% which drew a conclusion that waxy of 18 kg treatment is considered to be the strongest one. From the results described above, nitrous fertilization is essential to grow maize in agricultural fields with the stream. The optimum level of nitrous fertilization is considered 18 kg per 10a.

질소시비량이 중산간지 고품질 쌀 생산에 미치는 영향

강종래,김정태,백인열,김정일,Kang J.R.,Kim J.T.,Beg I.Y.,Kim J.I. 한국작물학회 2005 한국작물학회지 Vol.50 No.suppl1

중산간지에서의 질소 시비량(0, 5, 7, 9, 11, 14, 17kg/10a)이 쌀의 품질에 미치는 영향을 검토하기 위하여, 3가지 품종(상미벼, 화영벼, 주남벼)을 대상으로 하여, 2개년간의 시험결과를 요약하면 다음과 같다. 1. 식미치는 질소시비량과 품종과의 상호작용 효과가 있었다. 즉 주남벼의 경우는 질소시비량에 따른 식미치의 차이는 없었으나, 화영벼의 경우는 질소 무비구가 5, 7, 17kg/10a 시비구보다 식미치가 높았으며, 상미벼의 경우는 7kg 시비구가 9, 11, 14, 17kg 시비구보다, 0, 5kg 시비구가 14, 17kg/10a 시비구보다 식미치가 높았다. 결과적으로 식미치는 품종에 따라 질소시비량에 대해 다르게 반응하는 것으로 나타났다. 2. Amylose 함량은 질소시비량간의 유의차는 인정되지 않았으나, 품종간의 Amylose 함량은 차이가 있어 상미벼<화영벼<주남벼 순으로 그 함량이 낮았다. 3. 단백질의 함량에서는 질소시비량과 품종간의 상호작용 효과가 인정된바, 주남벼와 화영벼의 경우는 질소시비량에 따른 차이가 없었고, 상미벼는 질소시비량이 적을수록 단백질의 함량이 낮았다. 4. 완전미와 백미의 수량은 질소시비량이 증가할수록 높았고, 품종간의 차이는 없었다. 5. 종전의 표준시비량인 질소 11kg/10a 시비구와 고품질 쌀 생산을 위해 새롭게 추천된 9kg시비구간의 쌀의 품질에 유의차는 인정되지 않았다. 6. 본 시험의 결과를 종합하면, 질소시비량에 따른 쌀의 품질은 품종에 따라 그 반응의 차이가 있어, 상미벼는 7kg/10a, 화영벼는 11kg, 주남벼는 14kg의 질소시비 수준에서 품질이 우수하고 수량이 높았다. In order to find out better cultivation practices in mid-mountainous area to produce high quality rice, an experiment involving seven nitrogen fertilizer rates and three varieties was carried out, during past two years$(2003\~2004)$. There was an interaction effect on palatability of milled rice between nitrogen fertilizer rate and variety. The palatability of Junambyeo grown by the treatment of nitrogen fertilizer yale wasn't different across the rates significantly, but Hwayongbyeo's palatability grown by 0 kg/ha nitrogen treatment was better than 50, 70,170 kg/ha, and Sangmibyeo's palatability grown by 70 kg/ha nitrogen treatment was better than 90, 110, 140, 170 kg/ha. Amylose content of milled rice was showed without a significant difference between nitrogen fertilizer rate, but in between variety, the amylose content of Sangmibyeo was lower than Hwayongbyeo's, also Hwayongbyeo's amylose content was lower than Junambyeo's. Protein content of milled rice was showed an interaction effect between nitrogen fertilizer rate and variety. The protein content of Hwayongbyeo and Junambyeo grown by the treatment of nitrogen fertilizer rate wasn't different across the fertilizer yale significantly, but Sangmibyeo's protein content grown by 0 kg/ha nitrogen treatment was lower than the rest of treatments, and it's protein content grown by 50, 70, 90 and 110 kg/ha nitrogen treatment was lower than 140 and 170 kg/ha. Bead rice yield of milled rice grown by lower nitrogen fertilizer rate, was lower than that grown by higher nitrogen fertilizer rate. In a conclusion gathering all above the results to produce high quality rice in Mid-mountainous area, the applicative nitrogen fertilizer rate was 70 kg per ha for Sangmibyeo, 110 kg/ha for Hwayongbyeo and 140 kg/ha for Junambyeo, in considering with head rice yield, palatability, amylose${\cdot}$protein content and productivity.

경북 북부지역에서 파종량과 질소 시비량이 호밀의 종자생산에 미치는 영향

류정기,한옥규,박정현,황보순,조익환 한국국제농업개발학회 2016 韓國國際農業開發學會誌 Vol.28 No.3

The study was conducted to determine proper seeding rate and nitrogen fertilizer level for the effective seed production of Winter Rye (Secale cereale L.) with randomized block design with three replicates by combining both seeding rates (3, 5, and 7 kg/10a) and different nitrogen fertilizer application levels (0, 3, 6, and 9 kg/10a) in northern area of Gyeongbuk province from Oct. 7, 2013 to Jun. 15, 2014. Emergence and overwintering rates were not influenced but lodging degree was influenced by seeding rate and nitrogen fertilizer level. High lodging were observed at the seeding rates and nitrogen fertilizer levels of more than 5 kg/10a and 6 kg/10a, respectively (p < 0.01). Lodging less than 20% were observed at the seeding rate of 3 kg/10a regardless of the increase of nitrogen fertilizer level, furthermore, no lodging was shown though seeding rate was increased up to 7 kg/10a under the condition without nitrogen fertilizer. No. of leaves per plant, plant height and culm length were increased as affected by the increase of nitrogen fertilizer level rather than the increase of seeding rate. Spike length was shortened as affected by the increase of seeding rate while it was lengthened by the increase of nitrogen fertilizer level with no interaction effect between the two factors. No. of stems and spikes per m2 were influenced by the increase of nitrogen fertilizer level rather than by seeding rate with no interaction effect between the two factors. Grain yield was significantly increased as influenced by the increases of seeding rate (A) and nitrogen fertilizer level (B) with interaction effect (A × B), which resulted in the highest grain yield (310 kg/10a) at the seeding rate of 5 kg/10a and the nitrogen fertilizer level of 3 kg/ 10a. In conclusion, the proper seeding rate and fertilizer application level would be 5 kg/10a and 3 kg/ 10a, respectively to effectively produce the winter rye seeds in northern Gyeongbuk province.

질소시비가 쌀의 품질 특성과 취반미의 향기 성분에 미치는 영향

이광빈,전대경,채제천 韓國作物學會 2003 한국작물학회지 Vol.48 No.6

질소시비량이 쌀의 품질 특성과 취반미의 향기성분에 미치는 영향을 알고자, 조생종인 대진벼, 중만생종인 일품벼와 추청벼를 공시하고, 질소 시비수준을 0, 5.5, 11, 16.5kg/10a로 처리하여 2001년에 포장실험을 수행한 결과는 다음과 같다. 1. 질소시비량이 증가할수록 세 품종 모두 쌀 수량은 고도로 유의하게 증가하였는데(r=0.93**~textrm0.97**) 이는 단위면적당 수수가 유의하게 증가하였기 때문이었다. 2. 질소시비량이 증가함에 따라 현미 완전미율은 유의하게 감소하였고(-0.84**~-0.91**), 불완전미율은 유의하게 증가하였다. 3. 질소시비량이 증가할수록 현미의 단백질 함량은 세 품종 모두 유의하게 높아졌고, 아밀로스 함량은 대진벼와 일품 벼에서는 유의하게 높아졌으나, 추청벼는 일정한 경향을 보이지 않았다. 4. 기계적 식미값은 대진벼와 일품벼에서는 질소시비량 0-11kg/10a 사이에 차이가 없었고, 16.5kg/10a에서는 매우 유의하게 감소하였다. 추청벼는 질소시비량에 비례하여 식미 값이 유의하게 감소하였다. 5. 쌀의 단백질 함량과 질소시비량 간에는 고도로 유의한 정의 상관(r=0.88**~textrm0.96**)이, 질소시비량과 완전미율간에는 고도로 유의한 부의 상관(r=-0.84**~-0.91**)이, 그리고 질소시비량과 식미값 간에도 매우 유의한 부의 상관(r=-0.72**~-0.85**)이 나타났다. 6. 질소시비 처리한 추청벼 취반미의 취발성 방향 성분을 분석한 결과 총 11종이 검출되었다. 그러나 질소시비량이 증가함에 따라 방향 성분이 뚜렷하게 증가한다고 보기는 어려줬다. 7. 쌀의 수량과 품질을 동시에 고려할 때 질소시비량은 표준시비량(11kg/10a)이 가장 적정할 것으로 생각되며 식미를 높이기 위해 질소 시비량을 표준비 이하로 감소시킬 필요는 없을 것으로 판단되었다. This experiment was conducted in 2001 to investigate the effect of four nitrogen levels (0, 5.5, 11, 16.5kg/10a) on the yield and quality of vice especially with respect to eating quality. One early-maturing variety (Daejinbyeo) and two mid-late-maturing varieties (Ilpumbyeo and Chucheongbyeo) were used in this experiment. Rice yields of all varieties were increased by the higher rate of nitrogen application, mainly due to a larger number of panicles per m2. Head rice ratio was reduced significantly with an increased rate of nitrogen, while immature vice ratio was increased significantly. Increasing the nitrogen application rate, a considerable increase of protein content was found in all tested rice varieties. Palatability value of Daejinbyeo and Ilpumbyeo measured by rice taster was not affected by nitrogen application rate ranging from 0 to 11 kg/10a, but it was decreased significantly at the rate of 16.5kg/10a. In contrast, the palatability value of Chucheongbyeo was decreased significantly by increasing nitrogen application at the whole application rate. A positive correlation was found between nitrogen application rate and protein content (r=0.88**~textrm-0.96** ), but head rice (r=-0.84** ~-0.91** ) and palatability value (r=-0.72** ~-0.85** ) showed a negative correlation with the nitrogen application rate. Regardless of the fact that eleven aroma-active volatile compounds were detected in cooked vice of Chucheongbyeo, it was concluded that the aroma-active volatile compounds of cooked rice was not affected by the different nitrogen application rate. The results of this study showed that the standard nitrogen fertilization rate of 11kg/10a could be appropriate considering both rice yield and palatability.

Effect of Nitrogen Rate and Planting Density on Early Growth in Wheat

Chang Khil Song,Richard A Richards 韓國作物學會 1999 Korean journal of crop science Vol.44 No.1

This experiment was conducted with nine wheat geno-types to choose the wheat which has excellent early vigour. 'Vigour 18' and 'ZL 59A' are excellent in the long coleoptile genotype, while 'Amery' and 'Janz' are excellent in the short coleoptile genotype. Responding to the growth stage and nitrogen level, Vigour 18 is predominant in the long coleoptile genogype, while Janz in the short coleoptile genotype. Responding to sowing density and nitrogen level, the higher the sowing density was, the shorter the leaf area of Vigour 18 and Janz. Also the leaf area turned out to larger in the plot fertilized with high nitrogen than in the plot fertilized with low nitrogen. This is true of leaf weight and root weight. Concerning specific leaf area (SLA) and leaf area ratio (LAR), the higher the sowing density was, the SLA tended to grow larger, while the SLA grew larger in the plot fertilized with low nitrogen, as were found in Vigour 18 and Janz. The roots of long coleoptile genotype, Vigour 18, turned out to grow longest on the plot sown with 3 seeds. While the roots of short coleoptile genotype, Janz, grew longest on the plot sown with 2 seeds. The relative growth rate (RGR) was the same at low N rates and high N rates. The RGR was 0.071 and 0.072 g g-1d-1 at low N rates and high N rates. The partitioning of RGR into net assimilation rate (NAR) and LAR showed that the average LAR at low N rates was similar to the LAR at high N rates. Variation within each cultivar in the LAR and NAR was small relative to the difference between them at low N rates and high N rates. Above ground mass was 8.2 mg greater at high N rates than low N rates, whereas leaf area was 0.05 ~textrmm2 kg-l greater at high N rates than low N rates. The NAR was similar at low N rates and high N rates, whereas LAR was greater at high N rates (0.05 ~textrmm2 kg-l ); variation in SLA was responsible for the variation in NAR and LAR both at low N rates and high N rates. NAR was more closely associated with the reciprocal of SLA.

크리핑 벤트그라스 훼어웨이에서 관수회수.예지물과 질소시비수준이 엽조직 및 토양 질소함유량에 미치는 효과

김경남,로버트쉬어만 한국잔디학회 1997 한국잔디학회지 Vol.11 No.2

Responses of 'Penncross' creeping bentgrass turf to various fairway cultural practices are not well-established or supported by research results. This study was initiated to evaluate the effects of irrigation frequency, clipping return or removal, and nitrogen rate on leaf and soil nitrogen con-tent in the 'Penncross' creeping bentgrass (Agrostis palustris Huds.) turf. A 'Penncross' creeping bentgrass turf was established in 1988 on a Sharpsburg silty-clay loam (Typic Argiudoll). The experiment was conducted from 1989 to 1991 under nontraffic conditions. A split-split-plot experimental design was used. Daily or biweekly irrigation, clipping return or removal, and 5, 15, or 25 g N $m-^2$ $yr-^1$ were the main-, sub-, and sub-sub-plot treatments, respectively. Treatments were replicated 3 times in a randomized complete block design. The turf was mowed 4 times weekly at a l3 mm height of cut. Leaf tissue nitrogen content was analyzed twice in 1989 and three times in both 1990 and 1991. Leaf samples were collected from turfgrass plants in the treatment plots, dried immediately at 70˚C for 48 hours, and evaluated for total-N content, using the Kjeldahl method. Concurrently, six soil cores (18mm diam. by 200 mm depth) were collected, air dried, and analyzed for total-N content. Nitrogen analysis on the soil and leaf samples were made in the Soil and Plant Analyical Laboratory, at the University of Nebraska, Lincoln, USA. Data were analyzed as a split-split-plot with analysis of variance (ANOVA), using the General Linear Model procedures of the Statistical Analysis System. The nitrogen content of the leaf tissue is variable in creeping bentgrass fairway turf with clip-ping recycles, nitrogen application rate and time after establishment. Leaf tissue nitrogen content increased with clipping return and nitrogen rate. Plots treated with clipping return had 8% and 5% more nitrogen content in the leaf tissue in 1989 and 1990, respectively, as compared to plots treated with clipping removal. Plots applied with high-N level (25g N $m-^2$ $yr-^1$)had 10%, 17%, and 13% more nitrogen content in leaf tissue in 1989, 1990, and 1991, respectively, when compared with plots applied with low-N level (5g N $m-^2$ $yr-^1$). Overall observations during the study indicated that leaf tissue nitrogen content increased at any nitrogen rate with time after establishment. At the low-N level treatment (5g N $m-^2$ $yr-^1$ ), plots sampled in 1991 had 15% more leaf nitrogen content, as compared to plots sampled in 1989. Similar responses were also found from the high-N level treatment (25g N $m-^2$ $yr-^1$ ).Plots analyzed in 1991 were 18% higher than that of plots analyzed in 1989. No significant treatment effects were observed for soil nitrogen content over the first 3 years after establishment. Strategic management application is necessary for the golf course turf, depending on whether clippings return or not. Different approaches should be addressed to turf fertilization program from a standpoint of clipping recycles. It is recommended that regular analysis of the soil and leaf tissue of golf course turf must be made and fertilization program should be developed through the interpretation of its analytic data result. In golf courses where clippings are recycled, the fertilization program need to be adjusted, being 20% to 30% less nitrogen input over the clipping-removed areas. Key words: Agrostis palustris Huds., 'Penncross' creeping bentgrass fairway, Irrigation frequency, Clipping return, Nitrogen rate, Leaf nitrogen content, Soil nitrogen content.

연속회분식 공정에서 COD부하에 따른 질산화/탈질율 및 유출질소 분류

이재근 ( Jae Kune Lee ),임수빈 ( Soo Bin Yim ) 한국물환경학회 2008 한국물환경학회지 Vol.24 No.1

In this study, we investigated the nitrification/denitrification rate and classification of output nitrogen of a sequencing batch reactor (SBR) system with the variation of COD loads ; COD loads of 0.3, 0.4, 0.6, 0.7, 0.8, 1.0 and 1.2 kgCOD/m3·d were tested to determine the optimum conditions for the operation of the SBR and increase its nitrogen removal efficiency. As the COD loads increased, the nitrification rate at aerobic(I) period and the denitrification rate at anoxic(I) period were decreased. With the variation of COD loads, the amounts of nitrogen removed in the clarified water effluent were 63.9, `54.2, 34.7, 22.5, 13.7, 12.5 and 26.5 mg/cycle, respectively. The amounts of nitrogen removed during the sludge waste process were 19.5, 26.6, 41.0, 47.3, 58.1, 72.4 and 88.1 mg/cycle, respectively. The amounts of nitrogen removed by denitrification were 66.8, 69.3, 68.9, 56.5, 39.5, 7.3 and 0.0 mg/cycle, respectively, indicating that COD load more than 0.7 kgCOD/m3·d decreases the amounts of denitrified nitrogen. The nitrogen mass balances were calculated as the percentages of nitrogen removed in the clarified water effluent or by denitrification and sludge waste processing in each cycle of SBR operation and were 99.0, 98.5, 95.4, 82.1, 73.0, 60.5 and 74.8% for COD loads of 0.3, 0.4, 0.6, 0.7, 0.8, 1.0 and 1.2 kgCOD/m3·d, respectively.

Strain rate dependence of deformation behavior of high-nitrogen austenitic steels

Kim, Y.-S.,Nam, S.M.,Kim, S.-J. Elsevier 2007 Journal of materials processing technology Vol. No.

<P><B>Abstract</B></P><P>Tensile deformation of high-nitrogen austenitic steel under various strain rate conditions was characterized to investigate the deformation mechanism of the steel at different strain rates. Room-temperature tensile tests of the steel with nitrogen contents of 0.51wt.% and 0.88wt.% were performed at different strain rates ranging from 5×10<SUP>−5</SUP>s<SUP>−1</SUP> to 5×10<SUP>−1</SUP>s<SUP>−1</SUP>. Tensile curves of the steel were analyzed and compared, to obtain strain hardening characteristics, yield and tensile strengths as well as the elongation. Microstructures of the tested specimens were examined to understand the deformation behavior of the steel. The high-nitrogen steel with a complete austenite microstructure did not exhibit noticeable flow–stress dependence on strain rates. However, the steel with secondary phases such as nitrides in an austenite matrix showed strong strain rate dependency. The flow stress level increased significantly and the elongation decreased at strain rates higher than 5×10<SUP>−2</SUP>s<SUP>−1</SUP>. The change of the mechanical property became more significant as the nitrogen content in the steel increased. The deformation behavior of the nitrogen steel was elucidated by planar slip and twinning, which operated differently at different strain rates.</P>

스테인레스 용강내 질소 용해반응에 미치는 Ti 및 Nb의 영향

張民煥,洪仁國,朴鍾震,宋孝錫,李庸得 대한금속재료학회 2002 대한금속·재료학회지 Vol.40 No.3

A kinetic study of nitrogen dissolution in STS304 stainless steel melt containing Ti and Nb has been carried out at 1500℃ using an induction furnace and a levitation melting furnace. At low O and S levels, the nitrogen dissolution rate showed the first-order kinetics being controlled by the mass transfer of nitrogen in the melt. Ti addition to STS304 stainless melt significantly retarded the nitrogen dissolution rate by the formation of solid Ti oxide layer adhered on the melt surface. Nb did not affect the rate of nitrogen dissolution. In the levitation melting experiment where the oxide layer was removed from the melt surface, Ti did not retard the nitrogen dissolution rate. Simultaneous addition of Ti and Al increased the dissolution rate by the formation of non-wetting A1_20_3 on the melt surface. A small addition of CaO-Al_2O_3 synthetic flux to Ti containing melt was very effective to remove the oxide layer, hence to increase the nitrogen dissolution rate.

시설 참외 관비재배시 생육단계별 질소시비기준 설정

정규석(Kyu-Seok Jung),정강호(Kang-Ho Jung),박우균(Woo-Kyun Park),송요성(Yo-Sung Song),김계훈(Kye-Hoon Kim) 한국토양비료학회 2010 한국토양비료학회지 Vol.43 No.3

This experiment was conducted to establish the optimum nitrogen application level for oriental melon at Seong-ju Fruit Vegetable Experiment Station with a fertigation system. Four different levels of nitrogen fertigation were applied to oriental melon and growth of the plant was analyzed. Plant samples were collected 8 times and were analyzed by the standard methods. The first fertigation was applied at 10 days after transplanting for the oriental melon based on the growth rates of the plants. For oriental melon, 10 day interval fertigation and 8 time split application of fertilizer could be recommended. The amounts of N, P, and K fertilizer recommended by soil testing was 249-408-315 (kg ha<SUP>-1</SUP>). Treatment levels were 0, 0.5, 1.0, and 1.5 times of soil testing nitrogen with P and K level fixed. The total nitrogen (T-N) content in dried leaf showed a tendency to increase until 30 days after transplanting, then decreased. T-N content increased with increasing nitrogen fertigation rates. T-N content in dried fruit decreased slightly during the whole growing season. Fresh weight and nitrogen uptake were increased with increasing nitrogen fertigation rates. Total yield and marketable yield, 44,550 kg ha<SUP>-1</SUP> and 42,880 kg ha-1<SUP></SUP>, were maximized at 0.5 times of soil test nitrogen. Ratio of marketable fruit, 95%, was the highest at 0.5 times of soil test nitrogen. The optimum level of nitrogen for fertigation system was 0.5 times soil test nitrogen judging from total yield, commodity yield and commodity fruit.