• Korean Journal of Environmental Agriculture
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• v.20 no.1
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• pp.15-19
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• 2001

This study was carried out to investigate the effect of application time and amount of rice bran on rice yield, weed occurrence, and chemical change in water as applied at the level of 1.8 Mg/ha (1.8RB) and 3.5 Mg/ha (3.5RB) through field and pot experiment. $Nitrate(NO_3\;^-)$ in the surface water and the percolated water through pot were high in application of 3.5RB, and similar in application of 1.8RB as compared to chemical fertilization. Electric conductivity in surface water were higher by application of rice bran until 25 days after rice bran application. $NH_4-N$ in soil were lower in application of rice bran, and $NO_3-N$ in soil were higher in 3.5RB at tillering stage and panicle formation stage of rice. Rice bran application(3.5RB) showed 68% of weed occurrence as compared to that of chemical fertilization. Rice yield were increased by heavy application of rice bran; 4.41 Mg/ha in 1.8RB and 4.87 Mg/ha in 3.5RB, and top dressing of nitrogen at panicle formation stage caused to increased rice yield by $14{\sim}15%$. Rice yield was also increased by early application of rice bran.

• Journal of Food Hygiene and Safety
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• v.24 no.2
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• pp.111-123
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• 2009

We investigated the consumption inclinations of consumers for environmentally-friendly agricultural products (EFAP) for better production and distribution of EFAP. Consumer inclinations in large supermarkets from April 7th to 30th, 2008 were surveyed. Data were analyzed using the SPSSWIN 12.0 program. Results showed that 90.4% of consumers recognized EFAP and 76.4% of those who recognized the products had actually bought the products. Members of the "have purchased group" bought EFAP once a week because they believed these products were safe from hazards, such as pesticide. The amount spent on EFAP was less than 20% of the total food budget and the major consumed items were green vegetables and fruits. The sale location was mainly large supermarkets and agricultural cooperation outlets. Although many people were satisfied with EFAP from the viewpoint of nutritional and sensory qualities and safety compared with general agricultural products, they were notsatisfied with the price. Many consumers trusted that EFAP were safe and nutritional. Members of the "not purchased group" also trusted the nutritional and sensory qualities of EFAP and recognized the safety issue, but they were not satisfied with the price, compared with general agricultural products. Consequently, to succeed in the market, EFAP should maintain the confidence of the consumer while decreasing in price.

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.3
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• pp.151-156
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• 1986

There are differences in recommendations in the USA as to whether nitrogen fertilizer should be applied when establishing alfalfa (Medicago sativa L). The reason for not applying nitrogen is because some researchers found the addition of nitrogen reduced nodulation of alfalfa plants. A replicated experiment was conducted under controlled environmental conditions at the University of Nevada-Reno, Reno, Nevada, USA, to determine the effects of nitrogen application on seedling growth and nodulation of alfalfa when grown in a cool environment. A sterile sand was used in the growing media to which a complete nutrient solution minus nitrogen was applied volumetrically to each pot daily. Half of the pots received $NH_4NO_3$, at the rate of 11.2 kg/ha, at seeding and two and four weeks after planting, giving a total nitrogen application rate of 33.6 kg/ha. Rhizobia inoculant (R-12) consisted of a mixture of strains 171-15a. 1682c and 80 PI 265 of Rhizobium meliloti. Inoculant was applied to the seeds prior to planting and to the sand media at two and four weeks after seeding. Twenty seeds were planted in pots 14.0 cm in diameter and 11.5 cm deep. Seedlings were thinned after emergence to ten plants per pot. They were grown in a controlled environment chamber with a 16-hour light period. Soil temperatures at 6 cm depth ranged from $5.7^{\circ}C\;to\;21.5^{\circ}C$ and had a daily mean of $16.2^{\circ}C$ Plants were harvested at weekly intervals for seven weeks at which time root, shoot and total length, dry weight, volume and number of nodules per plant were determined. Root, shoot and total length were not affected by nitrogen fertilizer. However, application of nitrogen increased the size of the seedlings as determined by dry weight and volume when compared to plants which were not fertilized. This indicates that rhizobia did not fix enough atmospheric nitrogen to promote good growth. Nitrogen application resulted in significantly more nodules per plant. The effect of nitrogen fertilizer became more apparent as the plant became older. Results of this experiment show there are benefits from applying nitrogen at a low rate when establishing alfalfa under a cool environment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.4
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• pp.71-82
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• 1979

Transparent vinyl-mulching cultivation plots heavy-fertilized (6-14-20 kg $10a^{-1}\; of\; N-P_2O_5-K_2O)$ in growing peanuts produced 315-344Kg $10a^{-1}$ of quality kernels through improvement of the low temperature conditions of underground environment during the early growing stage and kernel-filling stage. The yields of which were 82-99 percent higher than that of conventional cultivation plot. The vinyl-mulching cultivation techniques accelerated emergence, young seedling growth, flowering, pod bearing and kernel filling of peanuts in Korea.

• Korean Journal of Environmental Agriculture
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• v.12 no.3
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• pp.219-229
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• 1993

Effects of paper mill sludge-fertilizers were investigated on the growth performances of tree seedlings under field conditions. Two types of sludge-fertilizers applied were an organic sludge compost and a processed sludge-pellet fertilizer strengthened with several components of organic and inorganic nutrients. Three species of tree seedlings studied were ibota privet(Ligustrum obtusifolium) and yellow poplar(Liriodendron tulipifera) of 1-0 year seedlings and also eastern white pine(Pinus strobus) of 2-2 year seedlings. Nitrogen and phosphorus contents of plot soil treated with sludge compost+sludge-pellet fertilizer+sludge-pellet fertilizer plot were increased to 8 times and 2.6 times as those of control plot, respectively. The growth performances of root collar diameter and seedling height were repeatedly measured up to five times through the growing season and the results were analyzed statistically by analysis of variance of randomized block design and Duncan's multiple range test. The growth performances of dry weight were measured after last fifth measurements.

• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.138-143
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• 2011

BACKGROUND: This study was conducted to investigate growth and yield of organically grown rice under a typhoon during a fall. The treatments included NPK chemical fertilizer, compost, oilcake, oilcake 2X, hairyvetch, and vetch+rye. METHODS AND RESULTS: Nutrient applications were made at rates equivalent to approximately 0.9 kg of actual N per acre. Oilcake and hairyvetch treatments had the lowest C:N ratio, but compost had the highest C:N ratio of 34:1. Rice treated by organic nutrient sources had great growth and development at the beginning of the growing season but had depressed growth and yield at the harvest. Oilcake 2X-treated rice in early growing season, especially, showed better growth and development than rice treated by other nutrient sources but was severely lodged at the harvest season due to the typhoon. Compost treatment with high C:N ratio slowly released inorganic N and produced poor rice growth and yield; however, it recued rice lodging. N uptake was the greatest for the oilcake 2X and vetch+rye treatments but the lowest for the compost, which was the similar pattern to the N use efficiency; the greatest and lowest N use efficiency was observed for the oilcake 2X (55%) and compost (5%), respectively. CONCLUSION(s): Rice lodging should be prevented by reducing the excessive nitrogen supplement, resulting from the lower C:N ratio of the organic materials as well as prevented by the radical midsummer drainage. Vetch+rye treatment with 25:1 of C:N had optimum vegetative growth and reduced rice lodging, which increased N use efficiency and yield.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.1
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• pp.7-14
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• 2001

This pot experiments was conducted to find out the forage productivity and quality in a grass/clover sward as affected by the application of three different fertilizers; double superphosphate(DS), fused Mg-phosphate(FP), and complex fertilizer(CF) on newly reclaimed hilly soil. This 2nd part was concerned with the contents and yields of mineral nutrients and general components. The results obtained are summarized as follows: 1. The concentrations of P, Ca. Mg, and Na by the forage species were relatively higher in the CF plots than in the FP and DS plots. The yields of mineral nutrients by the forage species were high in the order: CF>FP>DS plots. Especially. these were higher in the ladino clover and mixed forages than in orchardgrass. 2 The contents of crude protein and crude ash were highest with the CF plots, compared with the FP and DS plots. The yields of general components in the ladino clover and mixed forages were apparently highest with the CF plots. whereas these in orchardgrass not showed consistent differences among the plots. It was recognized that the positive effects on the concentrations and yields of mineral nutrients and general components in forages were higher in the order: CF＞FP＞DS plots.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.2
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• pp.159-166
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• 2011

This experiment was carried out to investigate the effect of application of swine slurry (SS) and slurry composting-biofilteration liquid fertilizer (SCB) on productivity of sorghum${\times}$sorghum hybrid (SSH) and soil environment in reclaimed land of Sukmoon in Korea. Dry matter (DM) yields of SSH in the treatments of SS and chemical fertilizer (CF) were higher than those of in SCB treatment in reclaimed land, but DM yields in SS and CF did not show a significant difference as compared to SCB. Nutritive values of SSH were not different among CF, SS and SCB. In soil samples collected at the end of the experiment, the concentration of organic matter was significantly increased by SS and SCB as compare to that at the beginning of the experiment (P<0.05), whereas the concentration of total nitrogen was not affected by SS and SCB. To investigate the moisture content of soil, the soils were collected from three layers; surface (0~5 cm), intermediate (10~15 cm), and deep (20~25 cm) layer. The moisture contents of soils increased according to the soil depth and the soil moisture was immediately affected by the amount of rainfall. Therefore, we suggest that the cultivation of SSH using SS in reclaimed land is possible and that additional nitrogen fertilizer was surely applied in case of application of SCB to cultivate SSH.

• Atmosphere
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• v.21 no.1
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• pp.57-67
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• 2011

Aerosol lidar ratio (extinction-to-backscatter ratio) at 532 nm was determined using 4-year measurements of elastic-backscatter lidar and sky radiometer at Seoul National University of Seoul, Korea. The mean lidar ratio (with standard deviation) based on 4 years of measurements is found to be $61.7{\pm}16.5$ sr, and weak seasonal variations are noted with a maximum in JJA ($68.1{\pm}16.8$ sr) and a minimum in DJF ($57.2{\pm}17.9$ sr). The lidar ratios for clean, dust, and polluted conditions are estimated to be $45.0{\pm}9.5$ sr, $51.7{\pm}13.7$ sr, and $62.2{\pm}13.2$ sr, respectively. While the lidar ratio for the polluted condition is appears to be consistent with previous studies, clean and dust conditions tend to have larger ratios, compared to previous estimates. This discrepancy is thought to be mainly due to the anthropogenic aerosols existing throughout the year around Seoul, which may cause increased lidar ratios even for clean and dust conditions.

• Korean journal of applied entomology
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• v.9 no.1
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• pp.7-13
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• 1970

1. Kum Nam Poong which is highly susceptible to bacterial leaf blight was used as the host plant throughout this experiment. Xanthomonas oryzae 6526 was inoculated on the top of upper leaves by single needle inoculation method. After 14 days, the enlarged spots were examined in the experimental pots. Each of 3 levels of nitrogen, phosphate and potassium pots were arranged at random with three replications. 2. The amounts of nitrogen fertilizer applied and the lesion development of bacterial leaf blight were positively correlated regardless of application of phosphate and potassium fertilizers. 3. The effect of phosphate fertilizer on the lesion development was not significantly different from standard level. The lesion development was stimulated when the amount of phosphate fertilizer was increased as twice as standard level. 4. The inhibitory effect of potassium fertilizer on leaf blight was maximum by applying standard level. The stimulative effect of potassium fertilizer on the lesion development, however, was noticed. when potassium fertilizer applied was increased as twice as the standard level. 5. The heading date and spike number of rice plant were significantly correlated with the lesion development, and such phenomena were depended on the amount of nitrogen fertilizer applied regardless of the other fertilizers applied in this experiment.