• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.1
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• pp.32-37
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• 2000

The in vitro culture of rice panicles is a culturing technique only panicle without other organs in culture solution containing organic substance, so that would be useful to study how assimilate supply affects grain development and maturation. To find the optimum stage for in vitro culture, rice panicles grown in greenhouse were sampled periodically after anthesis and cultured in nutrient medium. The panicles older than 1 weeks after anthesis had produced normal grains. Grain-filling was apparently dependent upon sucrose concentration (8-12 %) in medium, but not affected by nitrogen concentration supplied with glutamine. As far as rice panicle was supplied with sucrose and N in nutrient medium, grains continued accumulation of dry matter and maturation regardless to light condition. Considerably, grain-filling was improved when panicles were positioned horizontally inside flask, so that each grain was partially submerged to nutrient medium.

• Plant Resources
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• v.6 no.1
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• pp.11-15
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• 2003

To determine as optimal sowing time of forage rape in spring time in southern areas of Korea, forage rape cv. Velox, the highest yielding variety among introduced varieties of forage rape, was grown under five different sowing times. Yield components such as plant length, number of branches and number of leaves etc. were higher at the sowing time of Mar. 15 and Mar. 25. The plants sown at Mar. 15 and Mar. 25 also showed highest fresh and dry matter yield. When plants were grown under later sowing time, they showed higher values in content of crude protein and lower values in contents of crude fiber such as Neutral Detergent Fiber (NDF), Acid Detergent Fiber (ADF), cellulose and lignin. There was no relationship between variation of In Vitro Dry matter Digestibility (IVDMD) and sowing time. The plants sown at Mar. 15 and Mar. 25 showed highest digestible dry matter yields.

• Plant Resources
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• v.7 no.3
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• pp.170-173
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• 2004

To determine optimal plant density of forage rye in southern areas of Korea, forage rye cv. Paldanghomil, the highest yielding variety among experimental varieties of forage rye, was grown under five different plant density. Yield components such as plant height, and number of leaves were highest at the broad casting. Plants sown at broadcasting also showed highest fresh and dry matter yield. When plants were grown of the broad casting, they showed higher values in content of crude protein and lower values in contents of crude fiber such as neutral detergent fiber(NDF), acid detergent fiber(ADF), cellulose and lignin. There was no relationship between variation of in vitro dry matter digestibility(IVDMD) and plant density. Plants sown at the broad casting showed highest digestible dry matter yields.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1194-1196
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• 2003

Variations in soil physical and chemical properties can affect agricultural productivity and the environmental implications of crop production. These variations are present and may be important at regional, field, and sub-field (precision agriculture) scales. Because traditional measurements are time-consuming and expensive, reflectance-based estimates of soil properties such as texture, organic matter content, water content, and nutrient status are attractive. Soil properties have been related to reflectance measured with laboratory, in-field, airborne, and satellite sensors. Both multispectral and hyperspectral instruments have been used, with both natural and artificial illumination. Varying levels of accuracy have been obtained, with the best results (r > 0.95) using hyperspectral reflectance data to estimate soil organic matter and water content.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.11
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• pp.1713-1720
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• 2007

Influence of -110, +110, +220 and +330 mEq/kg of dry matter (DM) dietary cation-anion difference (DCAD) on growth performance of Thalli lambs were examined in a randomized complete block design. Four DCAD diets were randomly allotted to four groups, with ten lambs in each group. A linear increase in nutrient intake was recorded with increasing DCAD level. The digestibilities of nutrients were higher in lambs fed -110 DCAD diet than those fed +110, +220 and +330 DCAD diets. Lambs fed +330 DCAD diet had higher nitrogen balance than those fed -110 and +110 DCAD diets. Blood pH and serum $HCO_3$ increased with increasing DCAD level. Serum chloride was higher in lambs fed -110 DCAD diet, while serum (Na+K)-(Cl+S) increased linearly with increasing DCAD level. Serum calcium increased with decreasing DCAD level while serum magnesium and phosphorus remained unaffected. Lambs fed -110 DCAD diet had higher Ca balance than those fed +110, +220 and +330 DCAD diets. Urine pH increased with increasing DCAD level. Lambs fed +220 and +330 DCAD diets gained more weight than those fed -110 and +110 DCAD diets. In conclusion, increased DCAD level not only increased the dry matter intake but also improved the weight gain of growing Thalli lambs.

• Journal of Korean Society on Water Environment
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• v.28 no.2
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• pp.238-246
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• 2012

Organic matters budget in Lake Hoengseong were monthly investigated from April 2009 to November 2009. The intense rainfall occurred at between July and August and the hydrological factors were highly varied during the rainfall season. By the concentrated rainfall, the elevation, influx and efflux were sharply increased and the turbid water was also flowed into the middle water column in Lake. The inflow of turbid water increased the nutrient concentrations in water body and this appears to stimulate of phytoplankton regard as the primary productivity of influx of organic matter. Monthly average concentration of dissolved organic carbon (DOC) was generally higher than the particulate organic carbon (POC) concentration in Lake, but Temporal and spatial variation of POC concentration was higher than DOC and the maximum POC concentration was recorded in surface water in August, had the highest phytoplankton biomass. Organic carbon concentration in inflow site was rarely changed during the dry season, but the concentration was rapidly increased by the initial intense rainfall. In organic matters budget, the most of the organic matters was inflowed from the inflow site at rainfall season. Especially, the influx of allochthonous organic matters during the intense rainfall was 72.4% in the total influx organic matters.

• Journal of Environmental Health Sciences
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• v.17 no.1
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• pp.120-128
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• 1991

Saccharomyces cerevisiae was immobilized by incubating iron oxides with calcium alginate, and by polyacrylamide entrapment to use repeatedly for the conversion of glucose to ethanol. Magnetic and non-magnetic immobilized yeast and polyacrylamide immobilized yeast were compared with the native yeast a batch-fermentation of ethanol from glucose. Three kinds of immobilized yeast tended almost identically, having ethanol productivity as well as the final yield about the same to what was found for the native yeast. The long-term operational stability of three kinds of immobilized yeast were significant difference according as immobilized yeast activation or non-activation before ethanol fermentation. In the non-activation they lost their activity of fermentation rapidly in the beginning stage an slower at a later stage. On the other hand, in the activation with nutrient media, their activities were increased to some extent and stable in the later stage. The cell count of three kinds of immobilized yeast after activiation by incubating nutrient media, increased by a factor of about 45 to 48, whereas the fermenting capacity increased by a factor of 174 to 178. In the prearation of immobilized biocatalysts, magnetic matter does not seem to have any adverse affect on the properties of the microorganism. The immobilized biocatalysts by utilizing magnetic matter have some advantages, especially in application of viscous media or insoluble particle-containing media, for this work was linked with microbial utilization of environmental wastes and elimination of envirnmental pollutant.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.4
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• pp.399-406
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• 1997

This research was carried out to investigate the effect of zeranol injection on dry matter(DM) and nutrient intake requirement by growth stage of early castrated bull with 3 treatments(bul1, steer, steer+zeranol) with 28 Holstein bull at National Livestock Research Institute. The main results were as follows: DM intake at growing and fatting stage was the highest in steer groups, that the highest in bull groups at finishing stage and overall mean DM intake was 5% lower at steer+zeranol groups compared to bull and steer, respectively. Net energy intake at finishing stage was the highest as 35.49 Mcal at bull groups, while overall mean net energy intake was 101 - 109% of NRC requirement without significant difference. Concentrate intake to body weight was 1.68- 1.82, 1.91 -2.08 and 1.81 -2.05% at growing, fatting and finishing stage, respectively. Overall mean concentrate intake to body weight at steer groups was 1.94%, which is 1.8 and 1.81% higher compared to bull and steer+zeranol groups, respectively. Feed conversion ratio(DM) during overall period was the worst at steer groups as 9.321g, and also net energy conversion ratio was similar to DM conversion ratio.

• Plant Resources
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• v.6 no.2
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• pp.102-107
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• 2003

To find out the optimum fertilizer level for high yielding variety, Velox, experiment was conducted with 15 compositions of fertilizer levels at the experiment field of forage crop in Sunchon National University from Mar. 2000 to Aug. 2000. The effects of nitrogen fertilizer on plant growth were significant but increasing rate of application in potassium and phosphate fertilizers above 6 kg/a had negligible effects on plant growth. The optimum nitrogen application level of fertilizers turned out to be 16-6-6 kg/l0a of N-P$_2$O$_{5}$-K$_{5}$O. Content of crude protein was highest and that of crude fiber such as NDF, ADF, cellulose and lignin were lowest at this rate of fertilizer application. Furthermore, IVDMD was high and dry matter yield were highest at the optimum raterate

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.1
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• pp.13-17
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• 1994

To find out the effects of phosphatic fertilizer application level on the dry matter yield and nutrient contents of grasses, this experiment was arranged as a randomized complete block design with six treatments(0, 50, 100, 150, 200 and 250kg $P_2O_5$/ ha) and conducted at hill land in Gwangju, Gyeonggi Province from September, 1989 to October, 1992. The results obtained are summarized as follows : 1. As the phosphatic fertilization level increase, the early growth and cover degree of grasses wintered were more favorable and plant length was higher. 2. With 150kg $P_2O_5$/ ha application for three years, the average dry matter yield of grasses, 10,112kgl ha was sirnilared to that of 200kg $P_2O_5$/ ha and the yield was composed of 77.2% grasses(7,808kg/ ha), 19.2% legumes(l,937kg 1 ha) and 3.6% weeds(367kg / ha). 3. The crude protein and energy productivity of grasses increase as phosphatic fertilization level was increased, but those were not different between 150 and 250kg $P_2O_5$ 1 ha. Therefore, phosphatic fertilization level must be applied with 150kg / ha for a reasonable management in hilly grassland.