• Journal of The Korean Society of Grassland and Forage Science
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• v.43 no.2
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• pp.95-102
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• 2023

This study was to investigate the cultivation technique previously conducted cultivation research for the stable production of alfalfa and to present further research. The data used in the study were 270 alfalfa cultivation experimental data from 1983 to 2008, indicating the cultivation region, field type, variety, sowing, cutting frequency, fertilization, and dry matter yield (DMY). The average DMY of alfalfa in the Republic of Korea was 12,536 kg/ha, which differed greatly depending on the cultivated region. Most of the field type was cultivated in upland. In order to increase alfalfa production, it is necessary to use reclaimed and unused land, and research on the soil amendment matter to improve the soil condition is needed. Alfalfa varieties cultivated an amount of 53, but collected data no studies considered fall dormancy, the criteria for selecting alfalfa varieties, so further research is required. The fertilizer did not consider each component at various levels, and research is needed as the demand for fertilizer. In particular, research on potassium is needed considering the increase in alfalfa production. The alfalfa cutting frequency differed in the estimated pasture production period depending on the region, and the DMY tended to increase with increasing cutting frequency. This suggests that the alfalfa DMY can be increased according to the cutting frequency in the Republic of Korea, so research is needed to present the appropriate cutting frequency.

• Journal of The Korean Society of Grassland and Forage Science
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• v.8 no.2
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• pp.99-103
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• 1988

With a purpose of finding out the effects of magnesium and boron enriched organic-compound fertilizer application on qualities of grasses on the hilly pasture, a field experiment was arranged with five different treatments as a randomized block design and lasted from September, 1984 to the end of growing season in 1986. The results obtained are summarized as follows: 1. Mean chemical components except NFE of grasses at the plots with organic-compound fertilizer application were appeared to contain slightly high comparing to single dressing. 2. Production of DCP with organic-compound fertilizer (1,170.2 kg/ha) was significanty increased by 20% comparing to single dressing (975.7 kg/ha) in the conventional fertilization level (p<0.05), but it was not significantly different between them in the low dressing level. 3. Production of energies (TDN, StE and NEL) with organic-compound fertilizer of low and conventional dressing level were appeared to increase by 10 and 13 to 15% than those of single dressing of the same levels, respectively. But it was not significant difference. 4. Like single dressing nutrient productions with organic-compound fertilizer were appeared significantly high due to increasing of dressing gradually (P<0.05-0.01) 5. Mineral contents of P and Mg at the plots with organic-compound fertilizer were a little higher, on the other hand, K, C/P and K/Ca + Mg equivalent ratio were slightly lower than those of single dressing, but the content of Ca tended to similar between them.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.3
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• pp.257-262
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• 1981

Field experiment with 0, 100, 200, 400, and 800 kg-N/ha-year application levels was carried out to study the nitrogen response in the early stage of orchardgrass pasture establishment at College Fann, SNU, in 1979 and 1980. Both the highest dry matter yield and maximum percent of N recovery were obtained at the same level of 200 kg-N/ha in the year of seeding. but those of the next year were obtained at 400 kg-N/ha level. Leaf area indices (LAI) and net assimilation rates (NAR) during each regrowth periods as well as total nitrogen contents of forage at each cutting time increased with applied N in both years. The maximum crop growth rate (CGR) over two years was estimated to be obtained when LAI reached to about 5. The accumulation of NO_3 -N in forage started from 400kgㆍN/ha application in 1980. and exceeded the safe level for ruminants at the level of 800 kg-N/ha.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.1
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• pp.43-50
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• 1997

The aim of the study is to describe the fate and transformation of nitrogen in grassland ecosystems. Field experiments were conducted using sandyloam soil under variabling conditions: Zen, fertilization, reduced slurry application(l20kg N $ha^{-1}\;yr^{-1}$), usual sluny application (240 kg N $ha^{-1}\;yr^{-1}$).Soil water samples were gathered with 120cm ceramic cups with initial pressure of 0.5 bar. Samples were collected twice a month and analysed for NO, colormetrically. Percolation was calculated as the difference between precipitation and potential evapotranspiration, and leaching as the product of percolation and nitrate content of the water h m the ceramic cups. The N$H_4$-N content in soil had no significant effect on slurry application, but high slurry application on grassland resulted in high N$O_3$-N content in soil. The NO, concentration in soil water was remarkably variable during the year. The average N$O_3$, concentration during experiment became the lowest(8.5 mg/e ) without slurry application and highest with 240kOa cattle sluny(25.3 mg4 ). For each of the three different amounts of cattle sluny applied (0, 120, and 240kOa), the amount of N$O_3$-N leached per year were 12, 23 and 29kg/ha respectively. On grassland under the climatic conditions of Allgau showed enormous nitrate leaching, which has a p a t potential of polluting the ground water. The high pool of mineral N in the soil are the source for N$O_3$ leaching. The leaching of N$O_3$ cannot be avoided completely, but minimized by optimizing N fertilization rate.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.1
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• pp.1-5
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• 1991

Tall fescue(Festuca amndinacea Schreb.) is a productive pasture grass that is widely adapted to the soil and climate of Korea. It is regarded, however, as relatively low in palatability and nutritive value. On the other hand, Italian ryegrass(lo1ium rnultz$om Lam.) is highly nutritious and palatable, but is essentially weak in cold tolerance. Numerous investigators have succeeded in producing hybrids between Lolium spp. and Festuca spp. but no improved varieties have resulted. Therefore, intergeneric hybridization of Italian ryegrass with tall fescue is employed in 1984 to improve the adaptive and cold resistance quality of Italian ryegrass. In the mean time, F1-hybrid plants obtained by crossing Italian ryegrass x tall fescue were observed in open field. The results are summarized as follows: 1. Leaf-size and silica cell hair were intermediate between the types of parents but the shape of auricle tended to show Italian ryegrass and auricle-cilia to show tall fescue. 2. Roots of $F_1$-hybrid plants were mainly distributed at top soil and did not produced florescence material. 3. Head type of hybrids was intermediate between the types of parents but ray length was somewhat less than the length of tall fescue ray. Typical Italian ryegrass or tall fescue-like phenotypes were not observed. 4. Anthers of $F_1$-hybrid plants were formed but pollen were not formed. Even though pollen were formed, they were all empty. 5. Hybrid plants were more winterhardy and summer persistency than Italian ryegrass. They showed a equivalent growth to Italian ryegrass in spring and to tall fescue in summer. 6. Chromosome of $F_1$-hybrids was allopolyploid(2n=4~=28) and all $F_1$-hybrid plants were sterile.

• Journal of The Korean Society of Grassland and Forage Science
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• v.8 no.3
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• pp.99-103
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• 1988

With a purpose of finding out the effects of magnesium and boron enriched organic-compound fertilizer application on qualities of grasses on the hilly pasture, a field experiment was arranged with five dilferent treatments as a randomized block design and lasted from September, 1984 to the end of growing season in 1986. The results obtained are summarized as follows: 1. Mean chemical components except NFE of grasses at the plots with organic-compound fertilizer application were appeared to contain slightly high comparing to single dressing. 2. Production of DCP with organic-compound fertilizer (1,170.2 kg/ha) was significanty increased by 20% comparing to single dressing (975.7 kg/ha) in the conventional fertilization level (P<0.05), but it was not significantly different between them in the low dressing level. 3. Production of energies (TDN, StE and NEL) with organiccompound fertilizer of low and conventional dressing level were appeared to increase by 10 and 13 to 15% than those of single dressing of the same levels, respectively. But it was not significant difference. 4. Like single dressing nutrient productions with organic-compound fertilizer were appeared significantly high due to increasing of dressing gradually (P<0.05-0.01). 5. Mineral contents of P and Mg at the plots with organic-compound fertilizer were a little higher, on the other hand, K, C/P and K/Ca + Mg equivalent ratio were slightly lower than those of single dressing, but the content of Ca tended to similar between them.

• Korean Journal of Plant Resources
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• v.24 no.2
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• pp.214-235
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• 2011

The field survey to investigate the flora in Sogwang-ri, Uljin-gun, was carried out 10 times, from April 2009 to September 2010, and The results summarized as 430 taxa, 89 families, 253 genera, 367 species, 3 subspecies, 53 varieties, and 7 forms. Among these, 13 taxa were recorded as Korean endemic plant species and 11 taxa as rare plant species, which applied by the Korean Forest Service. Furthermore, 54 taxa were listed as specific plant species based on phytogeographical points of view and based on the list of those plants approved for delivery overseas, 17 taxa were recorded as such in the investigated area. There were 15 taxa identified as naturalized plants, and their naturalization ratio was found to be 3.4%. Among the 430 taxa, 178 taxa (40.9%) were categorized as edible plants, 145 taxa (33.7%) as medicinal plants, 114 taxa (26.5%) as pasture plants, 63 taxa (14.6%) as ornamental plants, 15 taxa (3.4%) as timber plants, 11 taxa (2.5%) as fiber plants, and 4 taxa (0.9%) as industrial plants.

• Journal of The Korean Society of Grassland and Forage Science
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• v.10 no.3
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• pp.152-157
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• 1990

To find out the effect of different patterns of nitrogen and potassium distribution on dry matter yield and botanical composition of temperate pastures, a field experiment was conducted with 6 treatments replicated 3 times in a randomized complete block design. It was lasted from September, 1986 to October, 1989 at the Livestock Experiment Station in Suweon. The results obtained are summarized as follows: 1. In early spring, winter hardiness, growth vigour, cold damage and coverage of grasses with 30% dressing of the total amount of N and K20 fertilizer in spring and at the 4th cutting time respectively were better than those of the other treatments. 2. Average dry matter yield for 3 years with heavy dressing in spring and at the 1st cutting time(l1, 187 kg DM/ha) was much more increased by 9% than that of the equally fertilized treatment(l0,24lkg DM/ha). 3. Changes in the botanical composition showed, in general, the same tendency for all treatments except equal N and K20 distribution. However, grassland vegetation with heavy dressing in spring and at the 1st cutting time was changed into relatively good botanical composition with 76.7% grasses, 22.3% legumes and 1.0% herbs at the end of the experiment. 4. By DM yield and botanical composition treatment 3(40-30-15-0-1570) seemed to be an optimal nitrogen and potassium distribution pattern in a temperate pasture.

• Korean Journal of Plant Resources
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• v.14 no.3
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• pp.259-276
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• 2001

Mt. Seoun(574 meters above sea level) is located in the southern part of An-sung city, Korea, within 36$^{\circ}$54'~36$^{\circ}$50'N, 127$^{\circ}$16'~127$^{\circ}$19'E. Field surveys were carried out nine times from March to October, 2000. Main results obtained from this study were as follows. The flora of vascular plants investigated in this survey was 439 taxa belonging to 90 families, 268 genera, 383 species, 49 varieties, 5 forma, 2 hybrid. As a result of this study, rare and endangered(Tricyrtis dilatata Nakai, Gastrodia elata Bl., Saururus chinenses Baill., Viola albida Palibin.) and many endemic species(Athyrium acatipinnulum Kodama., Tricyrtis dilatate Nakai, Paulownia coreana Uyeki., Salix hallaisanensis Lev., Asperula Iasiantha Nakai, Weigela subsessilis L.H. Bailey, Melamdryum seoulense Nakai, Clematis trichotoma Nakai, Spiraea prunifolia var. simpliciflora Nakai, Syringa dilatata Nakai, Chloranthus japonicus var. koreanus Sieb, Scutellaria insignis Nakai) of Korea were distributed in this area. Also the naturalized plants which were appeared in this area were 24 taxa(5.5 %). Among the plant resources, there are 239 taxa of edible plants(54.4%), 270 taxa of medicinal plants(61.5%), 217 taxa of ornamental plants(49.4%), 46 taxa of timber plants(10.5%) and 56 taxa of pasture plants(12.8%).

• Animal Bioscience
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• v.37 no.5
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• pp.817-825
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• 2024

Objective: The aim of this study was to identify suitable polynomial regression for modeling the average growth trajectory and to estimate the relative development of the rib eye area, scrotal circumference, and morphometric measurements of Guzerat young bulls. Methods: A total of 45 recently weaned males, aged 325.8±28.0 days and weighing 219.9±38.05 kg, were evaluated. The animals were kept on Brachiaria brizantha pastures, received multiple supplementations, and were managed under uniform conditions for 294 days, with evaluations conducted every 56 days. The average growth trajectory was adjusted using ordinary polynomials, Legendre polynomials, and quadratic B-splines. The coefficient of determination, mean absolute deviation, mean square error, the value of the restricted likelihood function, Akaike information criteria, and consistent Akaike information criteria were applied to assess the quality of the fits. For the study of allometric growth, the power model was applied. Results: Ordinary polynomial and Legendre polynomial models of the fifth order provided the best fits. B-splines yielded the best fits in comparing models with the same number of parameters. Based on the restricted likelihood function, Akaike's information criterion, and consistent Akaike's information criterion, the B-splines model with six intervals described the growth trajectory of evaluated animals more smoothly and consistently. In the study of allometric growth, the evaluated traits exhibited negative heterogeneity (b<1) relative to the animals' weight (p<0.01), indicating the precocity of Guzerat cattle for weight gain on pasture. Conclusion: Complementary studies of growth trajectory and allometry can help identify when an animal's weight changes and thus assist in decision-making regarding management practices, nutritional requirements, and genetic selection strategies to optimize growth and animal performance.