• 한국초지조사료학회지
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• 제18권2호
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• pp.123-128
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• 1998

1996년 작물시험장 전작포장에서 헤어리베치의 피복 및 질소시비가 옥수수의 생육 및 질소 흡수량 에 미치는 영향을 조사한 결과를 요약하면 다음과 같다. 봄 초 고사시키기 전 헤어리베치의 피복은 표 토충(O~7.5cm)과 충위 7.5~22cm에서 토양의 무기태 질소 함량을 감소시켰으나 옥수수 6엽기(추비시기)의 토양에서 무기태 질소 함량을 중가시켰다. 질소 비료 무시용시 헤어리베치의 피복은 출사시까지의 옥수수 생육, 건물중 그리고 출사기 질소 흡수량이 무피복에 비해 감소되었지만 출사기 이후 건물중이 회복되어 수확시에는 차이가 나타나지 않았다. 질소 비료 135kgFN/ha 시용시 헤어리베치의 피복은 옥수 수 출사기를 다소 늦추고 건물중을 무피복보다 감소 시켰으나 수확기에는 차이가 없었다. 질소비료 무시 용시 헤어리베치의 피복은 옥수수 전질소 흡수량을 중가시켰는데 이는 주로 출사기 이후의 질소 흡수량의 중가에 기언하였다. 헤어리베치의 피복에 관계없 이 질소비료 135kgFN/ha의 시용은 질소 무시용시 보다 옥수수 생육파 수량을 중가시 키고 수확시 질소 흡수량도 증가시켰는데 특히 무피복구에서 출사기까지의 질소 흡수량을 많이 중가시켰다. 시비한 질소비료는 주로 출사기 전에 주로 흡수되었고 헤어리 베치에서 무기화된 질소는 출사기 이후에 많이 흡수되었으므로 헤어리베치를 이용한 옥수수 재배에서는 옥수수의 초기생장 및 질소 흡수량을 중진시키기 위해서 헤어리베치에 의해 무기화 될 질소를 제외한 나머지 질소량은 옥수수 파종전 기비로 전량 시용하는 것이 바람직한 것으로 보였다.

• 한국작물학회지
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• 제64권2호
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• pp.102-108
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• 2019

본 연구는 식용옥수수 풋이삭의 식감의 결정에 영향을 미치는 과피의 두께를 측정하는 방법을 규명하기 위하여 과피 시료의 준비 방법에 따른 과피 두께의 차이와 등숙 시기별 과피 두께의 변화를 조사하기 위하여 수행하였다. 1. 찰옥수수와 초당옥수수 각 3품종의 시료를 수확 직후 생옥수수(생시료) 알곡을 바로 측정하거나 상온의 음지에서 완전(건조시료) 건조시키거나 $-4^{\circ}C$로 냉동시킨 후 과피를 측정하였다. 2. 시료 준비 방법과 등숙 시기에 따른 삼원 교호작용의 유의성이 인정되어 어느 한 요인에 대한 일반적인 결론을 도출하기 보다는 각 시료 준비 방법과 특정 등숙 시기에 따른 과피 두께의 비교를 수행하였다. 3. 초당옥수수는 건조시료에서 등숙이 진행됨에 따라 비교적 안정된 과피 두께 측정값을 얻을 수 있었으며 찰옥수수는 비해 모든 시료 준비 방법에서 초당옥수수보다 안정된 값을 보였다. 특히 풋찰옥수수 수확 적기인 수정 후 24일경에는 시료 준비 방법에 따른 차이는 크게 나타나지 않을 것으로 기대된다.

• 한국작물학회지
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• 제68권2호
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• pp.59-68
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• 2023

본 연구는 국립식량과학원에서 육성한 단옥수수 자식계통의 phytochemical 함량과 항산화 활성을 평가하여 고기능성 단옥수수 품종 육성을 위한 기초 자료로 이용하고자 수행하였다. 1. Carotenoid 함량이 가장 높은 계통은 KSE34 (1239.3±6.4 mg 100 g^-1), flavonoid 함량이 가장 높은 계통은 KSE6(68.6±9.6 mg CE 100 g^-1)으로 나타나 각 계통마다 화합물의 함량이 다양하였다. Phenolic compound 함량은 대부분의 단옥수수 자식계통에서 풍부하게 나타났으며, KSE8과 KSE25가 가장 높은 함량을 가진 계통이었다. 2. DPPH와 ABTS 라디칼 소거능으로 평가한 국내 단옥수수 자식계통의 항산화 활성 중 DPPH 활성은 계통 간에 다양하였으나, ABTS 활성은 차이가 적게 나타났다. KSE30과 KSE6이 각각 108.4±9.6 mg TE 100 g^-1, 104.2±12.8 mg TE 100 g^-1로 가장 좋은 DPPH 활성을 보인 계통이었으며 KSE47, KSE4, KSE21은 낮은 활성을 보였다. 3. 계층 군집 분석과 주성분 분석을 사용하여 단옥수수 자식계통의 농업적 특성을 비교하고 분류하였다. Carotenoid, polyphenol, flavonoid 함량이 높고 항산화 활성이 우수한 4개 계통(KSE6, KSE30, KSE34, KSE40)이 선발되었고, 향후 조합 능력 평가를 거쳐 고기능성 단옥수수 품종 개발에 활용할 것이다.

• Preventive Nutrition and Food Science
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• 제11권2호
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• pp.146-154
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• 2006

Structural modification of corn starch by gamma irradiation was evaluated for under dry conditions at varied intensities from 0 to 40 kGy. Under scanning electron microscopy, the granule shape of corn starch was not significantly affected by the irradiation up to 40 kGy. In addition, X-ray diffraction and melting patterns of the irradiated starches were similar to those of the native starch, indicating that crystalline regions in the starch granules were not changed by irradiation. However, the pattern of gel permeation column chromatography showed a significant increase in partial hydrolysis of gamma irradiated starch samples. The degree of polymerization and the paste viscosity of irradiated starch samples dose-dependently decreased significantly with irradiation, and increased solubility and clarity were observed in the irradiated starch solution. In addition, the degree of retrogradation decreased as irradiation dose increased. Irradiation of corn starch has advantages over the ordinary acid or the enzyme hydrolysis modification methods. It does not affect the granular shape and crystalline phase of starch during hydrolysis, and the process can be carried out in dry state.

• 한국토양비료학회지
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• 제46권6호
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• pp.510-518
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• 2013

Corn was mainly cultivated in slope land during summer season when heavy rain falls so that soil loss occurs severely. Especially, soil disturbance and exposure of topsoil by conventional tillage intensifies soil loss by heavy rain. The aim of this study was to develop surface covering and tillage methods for reducing soil loss in corn cultivation. The experiment was conducted in 17% sloped lysimeter with 8 treatments including strip tillage after surface covering with rye residue, strip tillage after residue covering of several crops and sod culture, black polyethylene film covering after conventional tillage and control. Amount of runoff water and eroded soil, and corn growth were investigated. Amounts of runoff water in all plots except black polyethylene plot ranged from 152 to 375 $m^3\;ha^{-1}$, accounting for 13~32% of 1,158 $m^3\;ha^{-1}$ in control. Amount of eroded soil decreased by 94 to 99% (3 to 89 kg $ha^{-1}$) in plots of strip tillage after covering with crop residues compared to control with 1,739 kg $ha^{-1}$. Corn yields in plots of strip tillage after covering with crop residues ranged from 6.0 to 6.9 Mg $ha^{-1}$, while that of control was 6.5 Mg $ha^{-1}$. The results suggest that strip tillage methods after surface covering with crop residues are very effective on soil conservation of slope land in corn cultivation.

• 한국토양비료학회지
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• 제47권2호
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• pp.92-99
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• 2014

The crop growing conditions make accurate predictions of yield ahead of harvest time difficult. Such predictions are needed by the government to estimate, ahead of time, the amount of crop required to be imported to meet the expected domestic shortfall. Corn and soybean especially are widely cultivated throughout the world and a staple food in many regions of the world. On the other hand, the CASA (Carnegie-Ames-Stanford Approach) model is a process-based model to estimate the land plant NPP (Net Primary Productivity) based on the plant growing mechanism. In this paper, therefore, a methodology for the estimation of corn/soybean yield ahead of harvest time is developed specifically for the growing conditions particular to Iowa and Illinois. The method is based on CASA model using MODIS data, and uses Net Primary Productivity (NPP) to predict corn/soybean yield. As a result, NPP at DOY 217 (in Illinois) and DOY 241 (in Iowa) tend to have high correlation with corn/soybean yields. The corn/soybean yields of Iowa in 2013 was estimated to be 11.24/3.55 ton/ha and Illinois was estimated to be 10.09/3.06 ton/ha. Errors were 6.06/17.58% and -10.64/-7.07%, respectively, compared with the yield forecast of the USDA. Crop yield distributions in 2013 were presented to show spatial variability in the state. This leads to the conclusion that NPP changes in the crop field were well reflected crop yield in this study.

• 한국초지조사료학회지
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• 제18권3호
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• pp.217-222
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• 1998

This experiment was carried out to investigate effects of herbicide application method on Calysteria jcqoonica control and corn yield at the forage experimental field, grassland and forage crops division, National Livestock Research Institute, RDA, Suwon from 1996 to 1997. The experiment was arranged in a randomized block design with three replication. The herbicide application consisted of control, 2~3 leaf stage(Dicamba), 5~6 leaf stage(Dicamba) and soil treatment (Pendimethalin). The hybrid of corn used in this experiment was P 3352. The results obtained are summarized as follow; 1. The plant height was the lowest at control and the highest at Dicamba treatment in 5~6 leaf stage, but no significant difference was found among herbicide application method at ear height. Tasseling and silking date were delayed 2~3 day at control. The length and weight of ear were highest at Dicamba treatment in 2~3 leaf stage. 2. The herbicide injury of corn was very slightly after 10-20 day, but corn was recovered soon. The weed control value was 94.2~67.5% at herbicide application plot. 3. The fresh and dry matter yield of Dicamba treatment in 2-3 leaf stage was highest as 42,878 and 16,033kg/ha, respectively. The application of Dicamba increased the DM yield of corn by 13~30%. 4. Herbicide application time had little effect on the ADF, NDF and CP contents, but the forage quality of ear was higher than that of stover. The result of this experiment indicate that the application of Dicamba in 2~6 leaf stage of corn will remove almost all of Calysreria jqonica and increase DM yield of com.

• 한국작물학회지
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• 제44권3호
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• pp.267-272
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• 1999

In order to determine the optimum harvest time of vegetable corns, the changes in sugars, soluble solids, and flavor of kernels of sweet (cv. ‘Golden Cross Bantam 70’), super sweet (cv. ‘Cocktail E-51’), and waxy corns (cv. ‘Chalok 2’) were observed at different ripening stages. Sucrose was a major sugar in the sweet and super sweet corns and the content increased from 15 to 21 and 27 days after silking (DAS), respectively and then decreased. Glucose and fructose contents of sweet and super sweet corns tended to decrease with kernel maturity. Total sugar content of the sweet corn analyzed by the anthrone method increased rapidly from 15 to 21 DAS, while that of the super sweet and the waxy corns increased slowly up to 24 and 26 DAS, respectively and decreased thereafter. The content of soluble solids in sweet corn was much higher than that of super sweet corn. Starch content of the sweet corn increased slowly from 15 to 33 DAS, while that of the super sweet corn increased a little rapidly from 15 to 21 DAS and then leveled off to 33 DAS. Starch content of the waxy corn increased continuously from 21 to 38 DAS. There was a positive correlation between the sum of individual sugars (sucrose, glucose, and fructose) and soluble solids in both sweet and super sweet corns, while the content of soluble solids was not related to the sum of individual sugars or total sugars. The flavor rate of sweet and super sweet corns maintained high between 21 and 27 DAS and that of waxy corn decreased from 24 to 33 DAS. The optimum harvest time for sweet, super sweet, and waxy corns was thought to be 21 to 24 DAS considering sugar and starch contents, flavor, and marketing.

• 한국기계가공학회지
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• 제19권2호
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• pp.24-29
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• 2020

In South Korea, agricultural mechanization has been carried out in paddy field, but not in the upland field during recent decades. Among crops such as root vegetables, leafy vegetables from upland field, corn is used as forage for livestock as well as food for men. The corn harvester needs to be developed to replace men's labor in rural area to follow the recent needs in the farm industry. The corn harvester is comprised of three parts such as cutting part, feeding part and pick-up part. The feeding part is so long for cut corns to be delivered from the cutting part to the pick-up part. Structurally, the load from the long moment arm is likely to be big. Thus, the setup to measure the stress on the duct of the feeding part was configured with the data acquisition system. The strain gages were attached on several points that seem to be loaded a lot comparatively. The stress was measured and the measured stresses were divided by the yield stress to get the safety factor. And then, we made sure the safety factors were above 1 on the all points. In conclusion, the feeding part of the corn harvester which convey the cut corn from the cutting part from the pick-up part can be regarded to be made safe structurally.

• 한국수산과학회지
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• 제44권5호
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• pp.560-564
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• 2011

Two feeding experiments were conducted to investigate the effects of dietary inclusion of genetically modified (GM) soybean and corn on the growth performance, feed utilization and body composition of juvenile abalone Haliotis discus hannai. Four isonitrogenous (31% crude protein) and isolipidic (6% crude lipid) diets (designated as nGM-soya, GM-soya, nGM-corn and GM-corn) were formulated to contain 20% non-GM (nGM) and GM soya and corn. Fifty juvenile abalone (initial body weight, 2.0 g) were distributed in each 50 L tank in a flow-through system. Each experimental diet was fed to duplicate groups of abalone to satiation once a day for 10 weeks. No effects of GM feedstuffs on survival were observed. Dietary inclusion of GM feedstuffs did not affect either growth performance or feed utilization of abalone. Body composition was not altered by the inclusion of GM feedstuffs. These results indicate that dietary inclusion of GM soybean and corn could have no effect on the growth performance and body composition of juvenile abalone. Further studies to investigate the effects of GM feedstuffs on transgenic fragment residues in ambient environments and in animals are necessary for the safe use of such ingredients in aquaculture.