• Weed & Turfgrass Science
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• v.3 no.4
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• pp.370-377
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• 2014

Research was initiated to evaluate cool-season grass (CSG) overseeding effects on coverage and species transition in Korean lawngrass (Zoysia japonica Steud.) and to determine CSGs and their seeding rate for a practical overseeding. Treatments were comprised of Kentucky bluegrass (KB, Poa pratensis L.), perennial ryegrass (PR, Lolium perenne L.), tall fescue (TF, Festuca arundinacea Schreb.) and their mixtures. Significant differences were observed in turfgrass coverage and species transition. Since overseeding, the coverage was highest in PR, followed by TF and lowest in KB. The highest coverage in polystand was associated with Mixture IV (TF 50 + PR 50) at a seeding rate of $150gm^{-2}$ which had highest PR and TF, but without KB. Regarding turfgrass transition, zoysiagrass recovery continued to come back up to 80% from late March. But it reduced after early October. Zoysiagrass in monostand was greatest in KB and lowest in TF, but variable in polystand. For the fast and great coverage in winter, it would be the best to apply with PR at $100gm^{-2}$ and equal combination of PR and TF by 1/2 in the mixture at $150gm^{-2}$. For the smooth spring transition to zoysiagrass, however, KB application at $50gm^{-2}$ is recommended.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.3
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• pp.84-95
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• 2001

This study was conducted to suggest the ecological restoration methods for the decomposed granite roadside cutslopes by Natural Topsoil Restoration Methods(NTRM). Four woody species, 3 shrub species, 4 native grasses, 8 wild flowers and 2 cool-season grasses were used. The experiment was conducted with the purpose of developing ecological restoration techniques by achieving following objectives for restoration by using native woody plants, shrubs, native plants and wild flowers; (1) prevention or reduction of wind and water erosion, (2) provision of food and cover for variety of animal species, (3) improvement of the visual or aesthetic quality of disturbed sites. The main results were summarized as follows. 1. Restoring naturalness to human-altered landscapes are important to protecting the worlds biodiversity. In this study, to restore or create an ecological community use as full a complement of native species as possible. Ecological restoration means returning a specific sites to its predisturbance condition. 2. Some species which are introduced first may inhibit the germination and growth of slower-growing species, or they may prevent the growth of other species whose propagules arrive later. In this study, cool season grasses was used small amount than native plants and woody species, because and Indigofera pseudo-tintoria grows well. Tall fescue and perennial ryegrass shows quick germination, but they could not inhibit the other species growing relatively slow. Pinus thunbergii used at Gonam near the ocean was suppressed by the other plants, so it can be concluded that using container seedlings is effective than seeding. 4. Ailanthus altissima, Albizzia julibrissin, Rhus chinensis Lespedeza cyrtobotrya, and Indigofera pseudo-tinctoria were germinated. In wild flowers, Coreopsis lanceolata, Dianthus sinensis, Coreopsis tinctoria, and Lotus corniculatus var. japonicus grew well and show enough plant height which will not suppressed by shrub and woody plants. After one year, native grasses such as Arundinella hirta, Miscanthus sinensis var. purpurascens and Imperata cylindrica var. koenigii cover the slopes well. 5. 25 herbaceous plants such as Trifolium repens, Arthraxon hispidus, Barbarea orthocerae, Potentilla fragarioides, Lepidium apetalum, Chenopodium album var. centrorubrum, Glycine soja, Rubus crataegifolius and 4 woody species such as Lespedeza maximowiczii, Robinia pseudoacacia, Symplocos Chinensis, Quercus acutissma were invaded. 6. Ecological restoration works by Natural Topsoil Restoration Methods for revegetation of the decomposed granite roadside cutslopes were successfully accomplished. It prevents surface water erosion and shows diverse vegetation structure. It will be successful to restore decomposed granite cutslopes.

• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.3
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• pp.167-172
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• 2007

Manure recycle is an emerging issue in agriculture in Korea these days. Farmers are keeping eye on legume mixture with grasses for nitrogen fixation and transfer to companion crops by legumes. We had a trial to investigate the effect of different legume mixtures on nitrogen fixation and transfer in spring soil. The treatment was arranged in a randomized complete block design with three replications. Three different mixtures were used(rye+hairy vetch, Italian ryegrass+crimson clover, oat+pea) and sowed in pots with paddy soil from western part of Korea(Seo Chon County). Pots with rye+vetch were transplanted from field of RDA(rural development administration) in Suwon on 2 February 2007 and other mixture treatments were sowed on early March with different sowing rate(7:3=Italian:crimson, 6:4=oat:pea). $(^{15}NH_4)_2SO_4$ solution at. $99.8\;atom%^{15}N$ was applied to the each pot at the rate of $2kg\;N\;ha^{-1}$. Application was done on 6 April at rye+vetch pots and remainder were applied on April 16. Forage were harvested from each pot at ground level in heading stage and separated into legume and grass. Total N content and $^{15}N$ value were determined using a continuous flow stable isotope ratio mass spectrometry. DM yield of rye+vetch, Italian+crimson and oat+pea were 6,607, 3,213 and 4,312 kg/ha, respectively. Proportion of N from fixation was 0.73(rye+vetch), 0.42(Italian+crimson) and 0.93(oat+pea). The percentages of N transfer from legume to grass were from 61% to 24% in different method by treatment and -35% to 21% in isotope dilution method.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.2
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• pp.180-187
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• 2015

This study was conducted to determine the effects of feeding by-product feed (BF)-based silage on the performance, blood metabolite parameters, and carcass characteristics of Hanwoo steers. The BF-based silage was composed of 50% spent mushroom substrate, 21% recycled poultry bedding, 15% cut ryegrass straw, 10.8% rice bran, 2% molasses, 0.6% bentonite, and 0.6% microbial additive (on a wet basis), and ensiled for over 5 d. Fifteen steers were allocated to three diets during the growing and fattening periods (3.1 and 9.8 months, respectively): a control diet (concentrate mix and free access to rice straw), a 50% BF-based silage diet (control diet+50% of maximum BF-based silage intake), and a 100% BF-based silage diet (the same amount of concentrate mix and ad libitum BF-based silage). The BF-based silage was fed during the growing and fattening periods, and was replaced with larger particles of rice straw during the finishing period. After 19.6 months of the whole period all the steers were slaughtered. Compared with feeding rice straw, feeding BF-based silage tended (p = 0.10) to increase the average daily gain (27%) and feed efficiency (18%) of the growing steers, caused by increased voluntary feed intake. Feeding BF-based silage had little effect on serum constituents, electrolytes, enzymes, or the blood cell profiles of fattening steers, except for low serum Ca and high blood urea concentrations (p<0.05). Feeding BF-based silage did not affect cold carcass weight, yield traits such as back fat thickness, longissimus muscle area, yield index or yield grade, or quality traits such as meat color, fat color, texture, maturity, marbling score, or quality grade. However, it improved good quality grade (1+ and 1++) appearance rates (60% for the control group vs 100% for the BF-based silage-fed groups). In conclusion, cheap BF-based silage could be successfully used as a good quality roughage source for beef cattle.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.3
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• pp.149-155
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• 2020

Cattle feeding in South Korea has been heavily dependent on domestically produced rice straw and imported grain. Around 42% of domestically produced rice straw is utilized for forage, and the remainder is recycled to restore soil fertility. Approximately 35% of round baleages were made with rice straw. However, higher quality hay is desired over rice straw. Due to increasing stockpiles of rice, there has been an economic burden on the government to store the surplus; therefore production of annual forage crops in rice fields has been further promoted in recent years. Hay import from the USA currently constitutes more than 80% of total imported hays. The main imported hays are alfalfa (Medicago sativa), timothy (Phleum pretense), and tall fescue (Festica arundinacea). The estimated forage required for cattle feeding was approximately 5.4 million MT in 2016. Domestically produced forage sates only 43% of that value, while low quality rice straw and imported hay covered the rest of demand by 33% and 20%, respectively. As utilization of domestically produced forage is more desirable for forage-based cattle production, long-term strategies have been necessary to promote domestic production of high quality baleage. One such strategy has been utilizing the fertile soil and abundance of fallow rice fields of western region of S. Korea to produce forage crops. Italian ryegrass (Lolium multiflorum) is the most successfully produced winter annual in the region and is approximately 56% of the total winter annual forage production. Forage sorghums (Sorghum bicolor), sorghum × sudangrass hybrids, and hybrid corn (Zea mays) produce a substantial amount of warm-season forage during summer. Produced forage has been largely stored through baleage due to heavy dew and frequent rains and has been evaluated according to S. Korea's newly implemented baleage commodity evaluation system. The system weighs 50% of its total grading points on moisture content because of its importance in deliverable DM content and desirable baleage fermentation; this has proved to be an effective method. Although further improvement is required for the future of forage production in South Korea, the current government-led forage production in rice fields has been able to alleviate some of the country's shortage for quality hay.

• Journal of Animal Science and Technology
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• v.57 no.3
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• pp.8.1-8.8
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• 2015

Background: The demand for healthy, lean and consistent meat products containing low saturated fatty acid content and high quality polyunsaturated fatty acids (PUFA), especially long-chain (${\geq}C_{20}$) omega-3 PUFA, has increased in recent times. Fat deposition is altered by both the genetic background and dietary supplements, and this study aimed to assess the effect of dietary Spirulina supplementation levels on the mRNA expression patterns of genes controlling lipid metabolism in the subcutaneous adipose tissue (SAT) and Longissimus dorsi (ld) muscle of Australian crossbred sheep. Methods: Twenty-four weaned lambs belonging to four breeds under the same management conditions were maintained on ryegrass pasture and fed three levels of Spirulina supplement (control, low and high). In terms of nutrient composition, Spirulina is a nutrient-rich supplement that contains all essential amino acids, vitamins and minerals. It also is a rich source of carotenoids and fatty acids, especially gamma-linolenic acid (GLA) that infer health benefits. After slaughter, subcutaneous adipose tissue (SAT) and ld samples were subjected to mRNA extraction and reverse transcription using quantitative polymerase chain reaction (RT-qPCR) to assess the mRNA expression levels of the Aralkylamine N-acetyltransferase (AANAT), Adrenergic beta-3 receptor (ADRB3), B-cell translocation gene 2 (BTG2) and Fatty acid synthase (FASN) genes, which are associated with lipid metabolism. Results: Both low and high Spirulina supplementation levels strongly up-regulated the transcription of all the selected genes in both SAT and ld tissues (mostly in the subcutaneous adipose), but sheep breed and sex did not influence the gene expression patterns in these tissues. Conclusions: The evidence indicates that high Spirulina supplementation level resulted in a decrease in intramuscular fat content in Australian purebred and crossbred sheep due to the enhanced production of melatonin in sheep muscle tissues and strong up-regulation of mRNA expression of BTG2 in SAT which negatively affected fat deposition. In contrast, low Spirulina supplementation level strongly up-regulated the ADRB3 and FASN genes responsible for fat production. These findings are consistent with the observed phenotypic data suggesting that low Spirulina supplementation level can increase lamb production, with higher long-chain PUFA content.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.4
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• pp.514-522
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• 2017

Objective: The study aimed to assess the N use efficiency (NUE) of pig slurry (in comparison with chemical fertilizer) for each regrowth yield and annual herbage production and their nutritive value. Methods: Consecutive field experiments were separately performed using a single application with a full dose of N (200 kg N/ha) in 2014 and by four split applications in 2015 in different sites. The experiment consisted of three treatments: i) control plots that received no additional N, ii) chemical fertilizer-N as urea, and iii) pig-slurry-N with five replicates. Results: The effect of N fertilization on herbage yield, N recovery in herbage, residual inorganic N in soil, and crude protein were significantly positive. When comparing the NUE between the two N sources (urea and pig slurry), pig slurry was significantly less effective for the earlier two regrowth periods, as shown by lower regrowth dry matter (DM) yield, N amount recovered in herbage, and inorganic N availability in soil at the 1st and 2nd cut compared to those of urea-applied plots. However, the effect of split application of the two N sources was significantly positive at the last two regrowth periods (at the 3rd and 4th cut). The two N sources and/or split application had little or no influence on neutral detergent fiber (NDF) content, acid detergent fiber (ADF) content, and in vitro DM digestibility, whereas cutting date was a large source of variation for these variables, resulting in a significant increase in in vitro DM digestibility for the last two regrowth periods when an increase in NDF and ADF content occurred. Split application of N reduced the N loss via nitrate leaching by 36% on average for the two N sources compared to a single application. Conclusion: The pig slurry-N was utilized as efficiently as urea-N for annual herbage yield, with a significant increase in NUE especially for the latter regrowth periods.

• Korean Journal of Weed Science
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• v.12 no.4
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• pp.387-392
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• 1992

For reducing the residual effects of Quinclorac to followed-by crops of paddy rice, three tests by different soil improvers, different cultural performances with tillage and application of composts, and cultivation of different depletion crops were evaluated, respectively. Among seven soil improvers, activated carbon, composts and perlite showed significant promisable feasibility to reduce phytotoxicity of tomato seedlings as affected by Quinclorac residuals, And comparing to untreated check, the application of tillage and composts prior to transplanting of tomato seedling could helpful to reduce Quinclorac residuals in the soil, but tomato and lettuce, most susceptible crops to Quinclorac, were not remarkably protected by those cultural performances. Also among cultivation of depletion crops just after rice harvest, Italian ryegrass, tall fescue, rape and oats engaged to deplete and reduce Quinclorac residuals for tomato seedling growth, however alfalfa and hairy vetch, relatively susceptible plants to Quinclorac were not promisable.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.9
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• pp.1374-1388
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• 2007

Three experiments were conducted to investigate the hypothesis that cows grazing on pasture produce the highest proportion of c-9 t-11 CLA in milk fat and no further increase can be achieved through supplementation of diets rich in linoleic acid, such as full-fat extruded soybeans or soybean oil. In experiment 1, 18 lactating Holstein cows were used in a randomized complete block design with measurements made from wk 4 to 6 of the experiment. In experiment 2, three cannulated lactating Holstein cows were used in a $3{\times}3$ Latin square design. Each period was 4 wk with measurements made in the final wk of each period. Cows in both experiments were assigned at random to treatments: a, conventional total mixed ration (TMR); b, pasture (PS); or c, PS supplemented with 2.5 kg/cow per day of full-fat extruded soybeans (PES). In both experiments, feed intake, milk yield, milk composition, and fatty acid profile of milk and blood serum were measured, along with fatty acid composition of bacteria harvested from rumen digesta in experiment 2. In experiment 3, 10 cows which had continuously grazed a pasture for six weeks were assigned to two groups, with one group (n = 5) on pasture diet alone (PS) and the other group (n = 5) supplemented with 452 g of soy oil/cow per day for 7 d (OIL). In experiment 1, cows in PS treatment produced 350% more c-9, t-11 CLA compared with cows in TMR treatment (1.70 vs. 0.5% of fat), with no further increase for cows in PES treatment (1.50% of fat). Serum c-9, t-11 CLA increased by 233% in PS treatment compared with TMR treatment (0.21 vs. 0.09% of fat) with no further increase for cows in PES treatment (0.18% of fat). In experiment 2, cows in PS treatment produced 300% more c-9 t-11 CLA in their milk fat compared with cows in TMR treatment (1.77 vs. 0.59% of fat), but no further increase for cows in PES treatment (1.84% of fat) was observed. Serum c-9, t-11 CLA increased by 250% for cows in PS treatment compared with cows in TMR treatment (0.27 vs. 0.11% of fat), with no further increase for cows in PES treatment (0.31% of fat). The c-9, t-11 CLA content of ruminal bacteria for cows in PS treatment was 200% or more of TMR treatment, but no further increase in bacterial c-9, t-11 CLA for cows in PES treatment was observed. Supplementation of soy oil in experiment 3 also did not increase the c-9 t-11 CLA content of milk fat compared with cows fed a full pasture diet (1.60 vs. 1.54% of fat). Based on these findings, it was concluded that supplementing with feeds rich in linoleic acid, such as full-fat extruded soybeans or an equivalent amount of soy oil, to cows grazing perennial ryegrass pasture may not increase milk fat c-9 t-11 CLA contents.

• Korean Journal of Agricultural Science
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• v.11 no.2
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• pp.183-189
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• 1984

This study was carried out to investigate the salt tolerance to the seed germination of 4 forage crops and their critical salt concentration. 1. The rate of seed germinations of 4 forage crops at 0.4% NaCl solution was not significantly decreased compared with control plot but the germination percentages at 0.8% NaCl solution were significantly dropped. 2. The days for germination were gradually delayed by increasing salt concentrations. 3. The growth of seedling root and shoot was slightly depressed at 0.4% salt solution but significantly depressed at 0.8% solution. At 1.2% salt solution, the seedling growth was stopped immediatly after seed germination. 4. The NaCl content in the seedling was increased at the medium containing higher amount of NaCl, however increasing rate of NaCl level in the seedling showed significant differences among the forage crops tested in this experiment. 5. The critical salt concentration to the germination of the forage crops was 0.4% to 0.8%. The perennial ryegrass showed the highest salt tolerance in the seed germination, and the tall fescue and the creeping red fescue showed medium, and the orchardgrass showed the lowest tolerance.