• Asian-Australasian Journal of Animal Sciences
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• v.29 no.6
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• pp.823-829
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• 2016

Eight Holstein steers ($216{\pm}48kg$ body weight) fitted with ruminal and duodenal cannulas were used to evaluate effects of wheat straw processing (ground vs pelleted) at two straw inclusion rates (7% and 14%; dry matter basis) in dry rolled or steam-flaked corn-based finishing diets on characteristics of digestion. The experimental design was a split plot consisting of two simultaneous $4{\times}4$ Latin squares. Increasing straw level reduced ruminal (p<0.01) and total tract (p = 0.03) organic matter (OM) digestion. As expected, increasing wheat straw level from 7% to 14% decreased (p<0.05) ruminal and total tract digestion of OM. Digestion of neutral detergent fiber (NDF) and starch, per se, were not affected (p>0.10) by wheat straw level. Likewise, straw level did not influence ruminal acetate and propionate molar proportions or estimated methane production (p>0.10). Pelleting straw did not affect ($p{\geq}0.48$) ruminal digestion of OM, NDF, and starch, or microbial efficiency. Ruminal feed N digestion was greater (7.4%; p = 0.02) for ground than for pelleted wheat straw diets. Although ruminal starch digestion was not affected by straw processing, post-ruminal (p<0.01), and total-tract starch (p = 0.05) digestion were greater for ground than for pelleted wheat straw diets, resulting in a tendency for increased post-ruminal (p = 0.06) and total tract (p = 0.07) OM digestion. Pelleting wheat straw decreased (p<0.01) ruminal pH, although ruminal volatile fatty acids (VFA) concentration and estimated methane were not affected ($p{\geq}0.27$). Ruminal digestion of OM and starch, and post-ruminal and total tract digestion of OM, starch and N were greater (p<0.01) for steam-flaked than for dry rolled corn-based diets. Ruminal NDF digestion was greater (p = 0.02) for dry rolled than for steam-flaked corn, although total tract NDF digestion was unaffected (p = 0.94). Ruminal microbial efficiency and ruminal degradation of feed N were not affected (p>0.14) by corn processing. However, microbial N flow to the small intestine and ruminal N efficiency (non-ammonia N flow to the small intestine/N intake) were greater (p<0.01) for steam-flaked than for dry rolled corn-based diets. Ruminal pH and total VFA concentration were not affected ($p{\geq}0.16$) by corn processing method. Compared with dry rolled corn, steam-flaked corn-based diets resulted in decreased acetate:propionate molar ratio (p = 0.02). It is concluded that at 7% or 14% straw inclusion rate, changes in physical characteristics of wheat straw brought about by pelleting negatively impact OM digestion of both steam-flaked and dry-rolled corn-based finishing diets. This effect is due to decreased post-ruminal starch digestion. Replacement of ground straw with pelleted straw also may decrease ruminal pH.

• Journal of The Korean Society of Grassland and Forage Science
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• v.28 no.4
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• pp.295-300
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• 2008

This experiment was conducted to compare forage production and feed value of winter forage crops at the experimental field of Livestock Division, National Institute of Animal Science from 2003 to 2004 in Jeju. The experiment was arranged in slit plot design with three replications. Main plots consisted of two cutting times, one time cutting and two times cutting. Sub plots consisted of 5 different seed combinations, T1 (Italian ryegrass), T2 (Oat), T3 (Italian ryegrass 25+Oat 75%), T4 (Italian ryegrass 50+Oat 50%), T5 (Italian ryegrass 75+Oat 25%). One time cutting showed the highest dry matter (DM) yield by 18,680 kg/ha. Tow times cutting showed the highest crude protein (CP) content by 11.97%. The all treatments have narrow range of total digestible nutrient (TDN) from 60.6% to 70.4%.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.2
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• pp.87-92
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• 2015

This experiment was conducted to evaluate the effect of seeding methods and application levels of nitrogen fertilizer on the yield and forage quality of whole crop rice (WCR). The WCR variety "Namil" was directly seeded on April 25 and transplanted on May 25. Five levels of nitrogen fertilizer were applied (90, 110, 140, 170 and 200 kg/ha). There were no significant differences (p<0.05) of the emergence date, heading date and disease resistance based on the nitrogen fertilizer rates; however, the WCR became dark at higher nitrogen fertilizer rates. The plant height increased at higher nitrogen fertilizer rates and the tiller number showed the same trend. In contrast to a direct seeding method, transplanting increased the tiller number. The dry matter (DM) content did not show a certain tendency based on nitrogen fertilizer rates, while the fresh and dry matter yields increased with incremental changes of the nitrogen fertilizer rates (p<0.01), and the transplant method increased the yield size. In yield analysis, the plot direct-seeded with 140 kg N/ha and the transplanting with 170kg N/ha showed the highest yields. The crude protein (CP) content increased with higher nitrogen fertilizer rate, but there was no significant differences between transplant and direct-seeding methods. The content of ADF (acid detergent fiber) and NDF (neutral detergent fiber) increased with higher nitrogen fertilizer rate, but total digestible nutrient (TDN) content decreased with increased nitrogen levels. Although high nitrogen applications increased the fresh and DM yields, the 140 kg/ha nitrogen fertilizer level is recommended as the proper nitrogen fertilizer level, considering both yield and the environments.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.3
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• pp.134-141
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• 2005

Cultivation of winter cover crops and its soil utilization for summer main crops in slope upland is very important at the respects of diminution of soil erosion and non-point pollution source. The effects of cover crop, hairy vetch as no-tillage or conventional tillage on prevention of soil erosion and reduction of chemical nitrogen fertilization were investigated in the slope upland with whiter clover living mulch (partial tillage) in Suwon for three years and with rye (conventional tillage) in Hongcheon for two years, respectively. In Suwon, amounts of soil lost by rainfall runoff decreased as much as 90% by hairy vetch-no tillage (HV-NT), white clover-partial tillage (WF-PT) together with the decrease of rainfall runoff compared to winter fallow with conventional tillage (WF-CT). In addition, amounts of weed also decreased as much as 80-90% by HV-NT and WF-PT. Corn yield decreased much at the plot of WF-PT mainly due to competition for soil water and nutrients between clover and corn at the early corn growth stage. On the contrary, corn yield increased by HV-NT compared to WF-CT regardless of weed control. In Hongcheon, amounts of soil eroded during winter season before corn seeding were reduced as much as 95% by cultivation of hairy vetch and rye compared to winter fallow. Amount of soil eroded during waxy corn growing season was reduced as much as 98% by HV-NT compared to WF-CT. Also, soil incorporation of hairy vetch and rye as green manure with conventional tillage at corn seeding time could reduce soil erosion as much as 70% compared to no soil cover with conventional tillage. Ear yields of waxy corn were increased 10% higher at hairy vetch green manure (HV-CT) without nitrogen fertilizer, 20% higher at HV-NT with standard nitrogen fertilizer, respectively than WF-CT. But ear yields of waxy corn were decreased by rye green manure (R-CT) and HV-NT at the condition of no nitrogen fertilizer. It was concluded that hairy vetch was better as winter cover crop to reduce both soil erosion and chemical nitrogen fertilizer simultaneously in slope upland than other cover crops.

• Korean Journal of Environmental Agriculture
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• v.25 no.4
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• pp.297-305
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• 2006

The field lysimeter experiment were undertaken to investigate the runoff and erosion loss of four pesticides from sloped land by rainfall and to assess the influence of pesticide properties, environmental factors and agricultural practices on them. The pesticide losses from soybean planted field and bare field were measured using field lysimeters. Pesticide losses from a series of lysimeter plots of sloped land by rainfall ranged $0.1{\sim}0.6%$ for alachlor, $1.1{\sim}4.5%$ for ethalfluralin, $8{\sim}31%$ for pendimethalin and 0.03% for ethoprophos, which were $1/3{\sim}2.5$ times to them in the simulated rainfall study. The erosion loss rates of pesticides from soybean-plots were $21{\sim}75%$ lower than the ones from bare soil plot. The effect of slope conditions was not great for runoff loss, but for erosion loss increased to maximum $4{\sim}12$ times by sloping degree and slope length. The peak runoff concentration in soybean-plots and bale soil plots were $3{\sim}278{\mu}gL^{-1}\;and\;6{\sim}450{\mu}gL^{-1}$ for alachlor, $1.1{\sim}11.4{\mu}gL^{-1}\;and\;0.9{\sim}16{\mu}gL^{-1}$ for ethalfluralin, $7{\sim}42{\mu}gL^{-1}\;and\;6{\sim}66{\mu}gL^{-1}$ for pendimethalin, and $2{\sim}53{\mu}gL^{-1}\;and\;0.1{\sim}113{\mu}gL^{-1}$ for ethoprophos, respectively, on nine different slope degree and slope length plots. Therefore, the differences of the peak runoff concentration between bare soil plots and soybean-plots were not great.

• Journal of Korean Society of Forest Science
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• v.49 no.1
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• pp.11-31
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• 1980

The morphological, anatomical and physiological traits were eximined for Populus alba ${\times}$ glandulosa which is an important planting species in Korea. The results obtained are as follows: 1. External characters in the leaf shape and chaff shape in the catkin were inherited as incomplete dominance but nectar gland was inherited as dominance. 2. Among the 15 selected clones, 9 clones were male, 2 clones female and 2 clones monoecious. 3. There were well-developed cork layers and bast fiber bundles in the bark. 4. Primordial leaves composed of 3 layers of cells and those undifferentiated into palisade and spongy parenchymas differed in its origin. 5. Leaf scare consisted of two kinds of tissues; one is connected to vascular bundle and the other not to vascular bundle. Tissues which had been connected to vascular bundle were isolated with only 2 or 3 layers of cork cells from the outside. 6. There was complicated arrangement in the vascular bundle of petioles. 7. Growth of the hybrid was sensitively influenced by external temperature, day-length and amount of light. In particular, it was apparent in height growth. 8. Flatness, loam soils and a $60{\times}60cm$ spacing might be best factors for the growth of P. alba ${\times}$ glandulosa. 9. The rooting of 15 clones was dependant upon external factors. 10. The growth of P. alba ${\times}$ glandulosa was best at around 80% of soil moisture content on the basis of plot water capacity. 11. Temperature difference between inside and outside stems below 100cm during the winter was the greatest at the south among seasons and among directions. 12. The sap movement was markedly influenced by air temperature, relative humidity in forest stand and moisture content in stem. 13. Total sugars in the cortex changed with season but did not differ in the dircetion of the stem. 14. Isoperoxidase variations in the leaf were different among 15 clones. Thus, it may be useful as a criterium for clonal identification. 15. The rate of soil moisture content decreased at a rapid slope was faster than that at a slow slope. Poor growth of P. alba ${\times}$ glandulosa at the slope was probably due to depletion of soil moisture.

• Korean Journal of Plant Resources
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• v.30 no.5
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• pp.556-564
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• 2017

Appropriate soil temperature and early planting of potato is very important for the successful potato-soybean cropping system in central region of South Korea. This experiment was carried out to determine the effect of mulching materials on the growth and yield of potato (Solanum tuberosum L.). Five different mulch treatments were had been applied on an upland soil as follows ; no mulch (NM), transparent film (TF), transparent film + additional transparent film (TF + ATF), black film (BF), and black film + additional transparent film (ATF). In the period of sowing time to removing additional films, mean soil temperature of the treatments was in the order of TF+ATF > TF > BR+ATF > BF as $20.3^{\circ}C$ > $18.5^{\circ}C$ > $16.1^{\circ}C$ > $15.4^{\circ}C$, respectively and that of NM was $13.8^{\circ}C$. The accumulated soil temperature was TF > NM > BF during the removing additional films to earthing at inter-tillage. On the changes in the soil temperature during a whole day, the temperature in the BF was lower than NM during around 18:00 PM to 12:00 NM, while NM was higher than BF in the time period of 10:00AM to 21:00PM. The sequence of potato sprout emergence was 15 > 18 > 20 > 22 days of TF+ATF, TF, BF+ATF, and BF, respectively and that of NM was 24 days. Comparing to the NM, potato sprout emergence was observed on the TF+ATF treated plot as early as 9 days. At 10 days before harvest, the significant difference in the tuber dry weight had been observed and the sequence tuber weight was in the order of TF > TF+ATF > BF+ATF > BF > NM. The potato yields of TF, TF+ATF, and BF+ATF were increased of 40.7, 37.3, and 22% as compared to NM ($2,805kg\;10a^{-1}$), but almost same yield in the BF. The differences of tuber dry weight and potato yields was co-related with the temperature rise of soil by the application of mulching materials on soil. Based on these results, application of mulching film had been very effective to increase the tuber size and the yield of potato by the temperature rise during seedling stage of potato. Transparent mulching was better than black mulching especially for the emergence of sprout of potato in relation to minimizing cooling injury.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.4
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• pp.337-344
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• 2017

This experiment was carried out to determine the effect of organic fertilizer and seed mixture on productivity, botanical composition and forage quality in middle areas(Geumsan, 250m sea level) pasture. Total six experimental pastures (orchardgrass, timothy and tall fescue based seed mixture and with or without organic fertilizer) were established in autumn, 2014 and evaluated productivity and agronomic characteristics from 2015 to 2016. Plant heigh was higher in orchardgrass based mixture and orchardgrass and tall fescue based mixture were higher in $2^{nd}$ harvest. There was not found the significant difference among treatment(P<0.05) in dry matter (DM) content. Botanical composition in $1^{st}$ harvest was higher weed portion in orchardgrass based mixture and legumes was disappeared at $3^{rd}$ harvest in all treatments. Fresh and dry matter yield was higher in $2^{nd}$ year than $1^{st}$ year. In $1^{st}$ year, orchardgrass based mixture with organic fertilizer plot was the highest(P<0.05) DM yield, but tall fescue based mixture with organic fertilizer was the highest in $2^{nd}$ year. Content of crude protein (CP) was the highest in tall fescue based mixture and Timothy based mixture showed low in ADF (acid detergent fiber) and NDF (neutral detergent fiber) content. But the content if in virto dry matter digestibility was higher than others. In $2^{nd}$ year, the nutritive value of $2^{nd}$ and $4^{th}$ harvested grasses were higher and average RFV (relative feed value) value was the highest at $4^{th}$ harvest. According to this result, orchardgrass and tall fescue based mixture would be recommendable for farm who considering productivity and timothy based mixture would be recommendable for considering forage quality in middle areas of Korea.

• Korean Journal of Environmental Agriculture
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• v.31 no.4
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• pp.318-327
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• 2012

BACKGROUND: For Non-Point Source(NPS) loads reduction, pollutant loads need to be quantified for major farming methods. The objective of this study was to evaluate impacts of farming methods on NPS pollutant loads from a paddy rice field during the growing season. METHODS AND RESULTS: The height of drainage outlet, amount of fertilizer, irrigation water quality were considered as farming factors for scenarios development. The control was derived from conventional farming methods and four different scenarios were developed based combination of farming factors. A field scale model, CREAMS-PADDY(Chemicals, Runoff, and Erosion from Agricultural Management Systems for PADDY), was used to calculate pollutant nutrient loads. The data collected from an experimental plot located downstream of the Idong reservoir were used for model calibration and validation. The simulation results agreed well with observed values during the calibration and validation periods. The calibrated model was used to evaluate farming scenarios in terms of NPS loads. Pollutant loads for T-N, T-P were reduced by 5~62%, 8~37% with increasing the height of drainage outlet from 100 mm of 100 mm, respectively. When amount of fertilizer was changed from standard to conventional, T-N, T-P pollutant loads were reduced by 0~22%, 0~24%. Irrigation water quality below water criteria IV of reservoir increased T-N of 9~65%, T-P of 9~47% in comparison with conventional. CONCLUSION(S): The results indicated that applying increased the height of drainage after midsummer drainage, standard fertilization level during non-rainy seasons, irrigation water quality below water criteria IV of reservoir were effective farming methods to reduce NPS pollutant loads from paddy in Korea.

• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.1
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• pp.44-52
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• 2018

This experiment was conducted at Suwon, Korea from 2013 to 2015. The objective of this study was to establish the optimum seeding rate, and to clarify the nitrogen fertilizer level for rye seed production in central and north area of Korea. We used Korean rye cultivar 'Gogu' for this test. We employed a split-plot design with three replications. The main plots were designed by three seeding levels (3, 5 and $7kg\;10a^{-1}$), but other sub-plots were randomly seeded. The plots were treated with three different nitrogen fertilizer levels (3, 6 and $9kg\;10a^{-1}$). The percentage of productive tiller, number of grain per spike, fertility rate, 1 liter weight, and 1000-grain weight decreased as seeding rate increased from $3kg\;10a^{-1}$ to $7kg\;10a^{-1}$, whereas the number of spike per $m^2$ increased. Therefore the grain yields of rye had less of an effect by increasing seeding rate. There was an increase in number of spike per $m^2$, number of grain per spike, and fertility rate as nitrogen fertilizer level increased from $3kg\;10a^{-1}$ to $9kg\;10a^{-1}$, but grain yields significantly not affected by the interaction of seeding rate ${\times}$ nitrogen fertilizer levels. However, the best seeding rate and nitrogen fertilizer level for rye seed production were 5 kg and $5{\sim}6kg\;10a^{-1}$, respectively, considering seed and fertilizer reduction and the prevention of pollution by excess fertilization.