• Journal of Animal Science and Technology
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• 제61권1호
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• pp.18-27
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• 2019

With South Korea's limited capability of feed production because of its relatively small cultivable area, the country is pushed to depend on foreign feed imports despite the immensely fluctuating price of corn. Hence, intensive efforts to increase the total cultivable area in Korea like extending of farming to mountainous area is being practiced. Corn was planted in Goesan County, a mountainous area in the country. Grain and stover were harvested separately in three harvest periods: early-harvest (Aug 8), mid-harvest (Aug 18), and late-harvest (Aug 28). The nutrient composition such as dry matter (DM), crude protein (CP), crude fat (EE), organic matter (OM), neutral detergent fiber (NDF), acid detergent fiber (ADF), and non-fibrous carbohydrates (NFC) was determined after harvest. Effective degradability (ED) of the major nutrients (DM, NDF, ADF, and CP) were measured through in vitro fermentation of rumen fluid from Hanwoo (Korean cattle). pH, ammonia-N concentration, volatile fatty acid (VFA) concentration, and gas production were periodically measured at 0, 3, 6, 12, 24, 48, and 72 h. Corn grain showed higher nutrient content and ED than stover. It also had higher gas production but its pH, ammonia-N, and total VFA concentration were lower than corn stover. The best nutrient composition of corn grain was observed in early-harvest (high CP, EE, NDF, OM, NFC, and low ADF). Early-harvest of corn grain also had high effective degradability of dry matter (EDDM), effective degradability of neutral detergent fiber (EDNDF), effective degradability of acid detergent fiber (EDADF), and total VFA concentration. On the other hand, the best nutrient composition of stover was observed in mid-harvest (high DM, CP, NDF, and low ADF). EDDM, EDNDF, and EDADF were pronounced in early-harvest and mid-harvest of stover but the latter showed high total VFA concentration. Hence, early and mid-harvested corn stover and grain in a mountainous area preserved their nutrients, which led to the effective degradation of major nutrients and high VFA production.

• 한국작물학회지
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• 제45권4호
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• pp.272-275
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• 2000

Winter green manure crops including legume increase grain yield of subsequent crop and substitute N fertilizer requirement with organic-No Hairy vetch grows vigorously and can provide N-rich green manure for corn with its soil incorporation after wintering. But, grain yield of corn as succeeding crop would be reduced if its planting time is delayed until late spring. This experiment was carried out to find the proper incorporation time of hairy vetch green manure and planting time of subsequent corn in cropping system with winter hairy vetch(green manure)-summer corn. Hairy vetch was incorporated into soil at a ten-day interval between April 10 and May 10 and corn was planted at 5 days after each hairy vetch incorporation. Soil nitrate concentration on April 10 and 20 in hairy vetch plot was slightly lower than that at winter fallow. Above-ground dry matter and organic-N of hairy vetch increased linearly with delayed hairy vetch incorporation time from April 10 to May 10. Average dry matter and organic-N produced by hairy vetch were 5.7 ton/ha and 248 kgN/ha, respectively. Corn growth and yield decreased as delayed corn planting time after May in spite of increasing dry matter and N-yield of hairy vetch. Nitrogen concentration of corn grain, stalk and whole plant at harvest were the highest in May 5 planting, but total N-uptake of May 5 planting were not different from that of April 25 planting because of lower grain yield. It was concluded that the proper incorporation time of hairy vetch and corn planting time were April 20 and April 25, respectively, because grain yield was the highest and corn could use hairy vetch-N effectively to produce dry matter.

• 농업과학연구
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• 제45권3호
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• pp.419-427
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• 2018

The present study was conducted to investigate the effect of different levels of Korean corn grain on in vitro ruminal fermentation with total mixed ration (TMR) as a basal feed. Three ruminal cannulated Holstein steers (Body Weight $479{\pm}33.0kg$) were used as rumen fluid donors. Treatments for in vitro fermentation were TMR only (control, 3.0 g), TMR substituted partially with high level (HC, TMR 1.5 and corn 1.5 g), and with low level of Korean corn grain (LC, TMR 2.25 and corn 0.75 g), respectively. To measure in vitro ruminal pH, gas production, ammonia N and volatile fatty acids (VFA), the in vitro fermentation incubation was triplicated at $39^{\circ}C$, 120 rpm for 0, 1, 3, 6, 12, 24 and 48 h, respectively. Mean ruminal pH was significantly lower (p < 0.05) for HC than control. Changes in rumen pH was rather similar between the groups till 6 h after incubation, but the lowest pH for HC (pH 5.10) appeared at 48 h compared with control and LC. Total gas production was tended (p < 0.09) to be higher and ammonia N was significantly lower (p < 0.05) for HC than control and LC. Total VFA was higher (p < 0.05) for HC and LC than control but no differences appeared between HC and LC. Overall, the present data indicate that feeding different levels of Korean domestic corn grain may lead to high and sustainable starch degradation in the rumen.

• Environmental Analysis Health and Toxicology
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• 제16권1호
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• pp.35-41
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• 2001

Barley or corn tea, which is usually prepared with municipal chlorinated tap water, is commonly consumed by the public as a substitute for the supplied water itself. This is because most people believe that harmful organic and inorganic compounds can be removed from the tap water by the adsorption mechanism during the tea preparation. In this study, three kinds of commercial grain tea materials-roasted barley grains, a tea bag containing barley grain pieces, and roasted corn grains-were tested for metal removal by preparing 1 liter of tea with deionized/distilled water according the manufacturer's recommended preparation procedures, assuming that the water is contaminated with eight selected metals at levels of 50$\mu\textrm{g}$/l. Of the tested teas, barley tea prepared with roasted grains showed the highest removal efficiency for Cu, As, Ni, Co, Pb, and Cd, ranging from 48 to 71%, followed by corn tea with roasted grains and barley tea with a tea bag. Cr was nearly maintained at the initial concentration in all kinds of tea. The Mn levels. however, were elevated during the tea preparation, particularly in both barley teas, probably because the metal was extracted into the water from the tea materials without significant adsorption. Therefore, it should be considered in the ingestion exposure analysis for metals that their concentrations are altered during the tea preparation with roasted barley or corn grain materials.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.84-84
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• 2022

The limit of crop cultivation is moving northward due to the temperature rise by climate change. There is a problem with crop growth if early sowing is performed at a time when the temperature is low. It is difficult to secure crop productivity and cultivation stability due to the low temperature and short cultivation period. Therefore, this study was conducted to analyze the change in growth characteristics and yield of corn for grain when early sowing is performed in central region of South Korea. This experiment was conducted at experimental field of Suwon in 2021. Three varieties of corn for grain such as Kwangpyeongok, Sinhwangok, and Hwangdaok were sown at intervals of 5 days from 20 March to 15 April. The planting density at this time was sown with a row interval of 70 cm and a plant interval of 25 cm. Nitrogen, phosphoric acid, and potassium fertilizers were applied at 17.4 kg, 3.0 kg, and 6.9 kg per 10a, respectively. Phosphoric acid and potassium fertilizers were all applied before sowing and nitrogen fertilizer was applied 50% before sowing and 50% in the fifth leaf period. The corn growth characteristics and yield components were investigated. The seedling establishment rate by sowing date was in the range of 68.5~88.5%, and it showed a difference depending on the variety. The range of days from sowing to tassel and silk emergence by sowing date was 79.9~98.4 and 81.0~98.9 days, respectively. As the sowing date was delayed, the days from sowing to tassel and silk emergence decreased. The growth characteristics and yield of corn by sowing date are as follows. Plant height was the highest at 241.3 cm at the sowing on 25 March, and Stalk diameter was the thickest at 25.6 mm at the sowing on 31 March. The fresh weight per plant was the highest at 728 g at the sowing on 25 March, and the dry weight per plant was the highest at 185 g at the sowing on 31 March. Corn growth characteristics did not show a certain trend depending on the sowing date, and corn growth was more vigorous at the sowing on March 25 and 31 than the others. In the case of ear weight, it was the heaviest with 344 g at the sowing on 25 March, and filled ear length ratio showed a tendency to decrease as the sowing time was delayed. The weight of 100 grains and grain yield per 10a of maize were the highest at 36.0g and 878.7kg/10a, respectively at the sowing on 25 March. Although the growth and yield of corn for grain were good during early sowing in the central region of South Korea, it is necessary to investigate the limit temperature for early sowing of corn by examining the annual variation according to weather conditions.

• 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.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.97-97
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• 2022

The yield characteristics of corn for feed by sowing period and the crude protein, crude fat, and coarse flour contents of grain in the harvesting period were compared. The varieties are Kwangpyeongok(KPO), Dapyeongok(DPO) and Pyeonggangok(PGO), and cultivation was tested by the National Food Engineering Department and the Central Crop Department. It was sown at a planting distance of 70×25cm on April 15, June 14, and July 15, 2021, and the amount of fertilizer was applied through soil inspection. For the growth characteristics, plant height, biomass and grain weight were investigated after 50 days of sowing, and general components were analyzed by drying and pulverizing each seed. Compared to the results of sowing in April, which is the right time to sow corn, all three varieties sown on June 14 showed an increase in biomass. In the case of sowing on July 15, the fresh weight of KPO and DPO decreased, and the grain weight of KPO and PGO decreased by 10-20% compared to the sowing in April. There was no significant difference in the crude protein content of grain according to the sowing seasons in April and June, but decreased in the corn sown in July. The crude fat content was highest in KPO sown on June 14 and DPO sown on July 15. Combining the yield and general composition results, it is thought that the cultivation of corn for feed in Suwon in the central part can be sown by mid-June.

• Journal of Animal Science and Technology
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• 제53권5호
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• pp.441-450
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• 2011

본 연구는 국내 농산부산물을 이용하여 in vitro 반추위 발효 특성을 조사하고 에너지 사료인 농후사료와 유사한 반추위 발효특성을 나타내는 농산부산물을 선정하여 최적배합수준을 통한 농후사료 대체 효과를 규명하기 위하여 수행하였다. 본 연구를 수행하기 위하여 국내에서 다량 생산되는 9점의 부산물(소맥피, 단백피, 제빵 부산물, 비지, 미강, 청치, 대두피, 주정박, 버섯배지)을 선발하였다. 1차 실험에서는 in vitro 배양을 통해 각각 원료사료의 시간대별(0, 3, 6, 12, 24, 48 h) 반추위 발효특성을 평가하였으며, 옥수수 및 대두박과 유사한 발효특성을 나타내는 원료사료 2종류를 선발 하였다. 최종적으로 선발된 2종류의 원료사료는 다른 원료사료와 혼합한 조합구를 만들어 in vitro 배양을 통한 옥수수와 대두박의 대체효과를 평가하였다. 실험설계는 옥수수와 대두박을 기본배합으로 하여, 알팔파, 티머시 건초 및 옥수수사일리지를 조사료로 사용하였다(T1). T2구는 대두박을 비지로 2.5% 대체, T3구는 옥수수를 청치로 15% 대체하였으며, T4구는 옥수수와 대두박을 청치와 비지로 각각 10 및 5% 대체하여 in vitro 반추위 발효특성을 평가하였다. 각 원료사료와 농산부산물의 in vitro 반추위 발효 특성을 조사한 결과, 옥수수 및 대두박과 유사한 발효특성을 나타내는 농산부산물로 청치와 비지를 선정하였다. 2차 실험에서는 pH의 경우, T4구에서 T1구와 비교하여 유의하게 낮았으며, 가스발생량은 T3 구에서 T1구와 비교하여 유의하게 높았다(p<0.05). 또한 건물 분해율은 3 및 24시간에 T4구에서 T1구와 비교하여 높았다(p<0.05). 결과적으로 농산부산물인 청치와 비지의 사용은 옥수수와 대두박을 일부 대체하기 위해 사용가능할 것으로 판단된다.

• 한국작물학회지
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• 제47권5호
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• pp.384-389
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• 2002

No-tillage (NT) practice for corn production has advantages of reduction of soil erosion and energy conservation. Research on effects of NT for sweet corn or super sweet corn is very limited. Hybrids of sugary (su) and shrunken-2 (sh2) were tested under NT and conventional tillage (CT) practices to investigate plant characters, ear characters, fresh yield, and grain yield. Sugary hybrids were Golden Cross Bantam 70 (GCB70), Sprint, Geumdanok, and Danok3. Shrunken-2 hybrids were BSS9472, Cambella90, GSS9299, Jubilee, KS-Y-65, and Chodangok1. Emergence rates under NT were lower than those under CT for su, while there was no difference between tillage systems for sh2. There were no differences between CT and NT for days to tasseling and silking, plant height, and ear height for both su and sh2. Ear characters such as ear length, number of kernel rows, number of kernels per row, and t100-kernel weight under NT were not significantly different from those under CT. There were no differences between two tillage practice for fresh and grain yield, rather they showed trend of increases under NT practices. Results from this trial indicate that NT practice for both su and sh2 cultivation may be possible to recommend to farmers.

• 한국세라믹학회지
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• 제40권1호
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• pp.5-10
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• 2003

Porous barium-strontium titanate ceramics were fabricated by adding corn- or potato-starch (are referred to as starch). The effect of sintering temperature on the microstructure and electrical properties of the porous ceramics was investigated. The room-temperature electrical resistivity of the barium-strontium titanate ceramics decreased with sintering temperature. The porosity and pore size were decreased and the grain size was increased with increasing the sintering temperature. The porosity and grain size of the barium-strontium titanate ceramics with corn-starch sintered at 1300 and 1450$^{\circ}C$ were 28.5, 22.6% and 3.2, 6.2 $\mu\textrm{m}$, respectively. The average pore sizes of the barium-strontium titanate ceramics with corn-starch sintered at 1300, 1400 and 1450$^{\circ}C$ were 0.5, 0.3 and 0.2 $\mu\textrm{m}$, respectively. The decrease in the room-temperature resistivity with increasing sintering temperature is attributed mainly due to the increase of grain size and the decrease of the electrical barrier height of grain boundaries as well as the partial decrease of porosity.