• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.2
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• pp.157-166
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• 1997

This study was carried out with aim to find out a tall fescue cultivar which is palatable and resistant to hot climate, and a white clover cultivar which is less competitive with other grasses. Pastures with 3 treatments (TI: Fawn, tall fescue + Regal, white clover + orchardgrass + perennial ryegrass, T2: Roa, tall fescue + Regal, white clover + orchardgrass + perennial ryegrass, T3 : Roa, tall fescue + Tahora, white clover + orchardgrass + perennial ryegrass) were established by oversowing. Under continuous grazing, dry matter yield, soil characteristics, botanical composition and nutrient contents of forages were investigated during the grazing seasons 60m 1994 to 1996. No significant difference were found in establishment percents, physical and chemical characteristics of soil, and nutrient contents of forages between 3 treatments(P>0.05). Dry matter yield of TI, T2 and T3 were 24,188, 23,827 and 23,578kg/ha, respectively. Fawn and Roa, tall fescue cultivars occupied 6.1 and 4.8% of the total plants in 1994, 14.4 and 11.5 % in 1995, and 28.4% and 17.7% in 1996, respectively. These results indicate that Fawn, tall fescue dominantly occupied with time more than Roa, tall fescue. There were no differences in percentage of Regal and Tahora, white clover cultivars(P > 0.05), showing 4.2 and 2.4% in 1994, 16.1 and 17.3% in 1995, and 2.4 and 1.0% in 1996, respectively. The percentage of orchardgrass on mixed pasture decreased after summer season of high temperature, but percentage of Roa, tall fescue slowly increased with time firom 1994 to 1996.

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.4
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• pp.285-294
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• 2000

To investigate the effect of Mycorrhiza (Glomus intradics) and Rhizobium inoculation on the N, P utilization and growth response of Alfalfa (Medicago saliva L.) and Perennial ryegrass (Lolium perenne L.) in mixed sward, four treatments (non-inoculation, Control; Mycorrhiza inoculation: M; Rhizobium inoculation, R and Mycorrhiza and Rhizobium inoculation, M+R) were applied. The associated analyses were canied out on the early vegetative growth stage (DAS 56, 56 days after seeding) and on the early flowering stage (DAS 126). The decreased rate of total N and P content in soil, with advancing plant growth, was relatively higher in the M and M + R treatment than control. The content of availabie phosphorus in soil at DAS 126 increased by about 34 and 38 % in M and M+R treatment compared to control (189.2 mg PzOskg DM), while non-significant changes was observed in R treatment. Total N uptake and P uptake in the control at DAS 126 were 44.71 and 3.52 mglplant in mixed sward, respectively. About 71, 98 and 197 % of increases in total N uptake and 70, 72 and 11 1 % of increases in total P uptake were estimated in M, R and M+R treatment. Comparing to control, total dry matter yield significantly increased by 27, 33 and 53 %, and crude protein yield also by 78, 83 and 204 %, respectively, in M, R and M+R treatment. The present data indicated that mycorrhiza orland rhizobium inoculation improved N, P utilization of both alfalfa and perennial ryegrass plants, and consequently increased total yield (especially by dual inoculation, M+R). (Key words : Alfalfa, Perennial ryegrass, Mycorrhiza, Rhizobium, N and P Utilization, Growth, Yield)

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.4
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• pp.283-290
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• 1996

This experiment was carried out to determine the effects of soil condition that previous crop cultivated after [TO: Soil of corn cultivated, T1 : Soil of rye monoculture cultivated(l50kg/ha), T2 : Soil of mixedculture cultivated(Rye : Red clover = 120 : 3koa). T3 : Soil of mixed-culture cultivated(Rye : Red clover = 90 : 6kg/ ha), T4 : Soil of mixedculture cultivated(Rye : Red clover = 60 : 9kg/ha), T5 : Soil of mixedculture cultivated (Rye: Red clover = 30 : 12kg/ha), T6 : Soil of red clover monoculture cultivated(l5kgha)) on the growth characteristics and nutrient yield of silage corn. The results are summarized as follows. 1. The plant length of silage corn was high in order of T6>T5>T4 treatment. In the leaf length, T5 and T6 treatment showed short compared to the other treatments, but they were wider than the other treatments in leaf width. In the number of leaf, T6 treatment was the highest as 14 leaves per plant, while T1 treatment showed lower than the other treatments as 12.6 leaves per plant. 2. In the stem hardness, ear length, ear width and ear full degree, soil treatment of red clover mono-culture cultivation(T6) showed higher than the other treatment as 5.1 1kg/$cm^2$, 20.8~~1, 7.7cm and 97%. respectively (P<0.01, 0.05). Ihe leaf of summer depression did not many occurrence, but T6 treatment was lower than the other treatment as 0.8 leaf per plant. 3. ADF and NDF composition were not affected by soil condition. Crude protein composition of T6 treatment was the highest as 7.8%. while TI treatment was the lowest as 6.9%. Fresh weight yield(59,083kg/ha), dry matter yield(21,743kg/ha), crude protein yield(l,369kg/ha) and TDN yield(15,800kg/ha) at T6 treatment were much more increased by 41.9, 47.5, 57.4 and 49% than TI treatment(39,410, 14,259, 827 and 10,056kg/ha).

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.3
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• pp.213-222
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• 1997

This study was carried out to investigate the reproduction efficiency and disease of Holstein heifer grazed on mixed pasture desighed with association of tall fescue and white clover cultivar (3 treatments = TI : Tall fescue Fawn + White clover Regal + Orchardgrass + Perennial ryegrass, T2 : Tall fescue Roa + Ladino clover Regal + Orchardgrass + Perennial ryegrass, T3 : Tall fescue Roa + White clover Tahora + Orchardgrass + Perennial ryegrass) on reproduction efficiency and disease in Holstein heifers, ftom April 1994 to November 1996. The results are as follows: 1. Erythrocyte counts, hemoglobin and packed cell volume of hematological values were $8.12\times10^6/{\mu}\ell, 9.9g/m\ell and 30.6m\ell/100m\ell$ respectively. While those were decreased to $4.84~5.93 \times10^6/{\mu}\ell, 7.0~7.8g/100m\ell and 22.8~28.3m\ell/100m\ell$, on pastuage (May-August), WBC counts was increased from $14.4\times10^3/{\mu}\ell to 14.0~18.3 \times 10^{3/\mu\ell}$ on pasturage. No significant differences were detected among the treatments on pastures. 2. Parasitemia levels increased to $14.0\pm8.2$(parasite/1,000rbc) at 1 month after pasturage. 3. At the occurrence of tirst estrus and conception, the average age of the Holstein heifers was $14.3\pm1.9$ and $17.4\pm1.5$ months, respectively, and the average interval of estrus cycle was $20.6\pm1.0$ days. Howerer, there was no significant difference on reproductive efficiency among 3 treatments. 4. The outbreak of diseases were tick bane disease, pink eye, pneumonia, mastitis, gastroentitis, waterpoisoning ringworm papillon and atosis during pasturage period(may-october). These diseases were showed no significant difference among 3 treatments. 5. In conclusion, there are no significant difference on the reproductive effeciency and disease outbreak among three treatments.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.3
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• pp.205-212
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• 1997

Forty-five holstein calves (average liveweight 150kg) were used to investigate the effect of combination of tall fescue and white clover cultivars on liveweight gain and feed efficiency into animal product in pastures. Daily gains per head for 3 years in T1, T2 and T3 (TI : Fawn, tall fescue + Regal, white clover + orchardgrass + perennial ryegrass, T2 : Roa, tall fescue + Regal, white clover + orchardgrass + perennial ryegrass, T3 : Roa, tall fescue + Tahora, white clover + orchardgrass + perennial ryegrass) were 0.27, 0.37 and 0.35kg, respectively, while average daily weight gains per ha were 3.54, 4.47 and 4.43kg, respectively. Animals grazing on mixed pasture with Roa tall fescue and Regal or Tahora white clover were showed a higher liveweight gain than those grazed on pastures with Fawn tall fescue and Regal h i t e clover. There was no significant difference among treatments (TI = 5.0kg T2 = 4.8kg T3 = 4.9kg) in herbage intake but feed efficiency into animal product was showed higher in T2 and T3 in comparison with T1(7.9% in T2 and 8.0% in T3 vs 5.97% in TI). In conclusion, association with Roa tall fescue and Regal white clover in mixed pasture can obtain higher animal product under continuous grazing system than that with Fawn tall fescue and Regal white clover.

• Journal of The Korean Society of Grassland and Forage Science
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• v.9 no.1
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• pp.34-42
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• 1989

This pot experiments were conducted to find out the optimal fertilization ratios of ${\Sigma}anion$ : ${\Sigma}cation$, ${\Sigma}A$/${\Sigma}C$, and the optimal application rates of total major nutrients in an orchardgrass/ladino clover mixed sward. The optimum ratios and concentrations in equivalent basis were computed by the Homes systematic variations technique. The results were summarized as follows; 1. The optimum fertilization ratios of ${\Sigma}A$ : ${\Sigma}C$ and the optimum application rates of total nutrients for the high yields by forage species in a mixed sward were obtained (Table 6 in detail); ${\Sigma}A$ : ${\Sigma}C$ = 2 : 1 at 80 and 320 meq/pot, and 3 : 2 at 560 and 800 meq for grass and grass plus legume, and ${\Sigma}A$ : ${\Sigma}C$ = 1 : 2 for legume in general. 2. The optimum application rates of total nutrients for the high yields of grass and grass plus kgum were increased by decreasing the ${\Sigma}A$/ ${\Sigma}C$: ratio, whereas these for legume showed a valible. range without significance. 3. The yields 01 grass and grass plus legume were generally increasing by increasing both the ${\Sigma}A$/ ${\Sigma}C$ ratio and total concentration, but they were significantly higher at the ${\Sigma}A$/ ${\Sigma}C$ = 1.273 than at the 2.125 under the high total ion concentration. The legume yields were proportional to ${\Sigma}C$ ratio and increased by increasing the total ion concentration under the condition of high ${\Sigma}C$ ratio. 4. The efficiencies of ${\Sigma}A$ and ${\Sigma}C$ in relation to the grass and grass plus legume yields were highest with the low ratios of each other and the low rates of total nutrients ${\Sigma}A$ efficiency m the legume yield tended to be similar to that of ${\Sigma}A$ in the grass yield noted above. The ${\Sigma}C$ efficiency in the legume yield, however, was generally proportional to the ${\Sigma}C$ ratio except at the low rate of 80 meqlpot. 5. The yields of grass plus legume, yield components and botanical compositions in a mixed sward were greatly influenced by the ${\Sigma}A$/${\Sigma}C$ ratios, the fertilization rates of total nutrients, and the interaction of ratio and rate noted above. These effects were generally different and opposite accading to grass and legume. In addition, the soil chemical properties and mineral contents of forages were partially influenced by these systematic variations.

• The korean journal of orthodontics
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• v.37 no.3 s.122
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• pp.171-181
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• 2007

Objective: The present study was aimed at an analytical formulation of the micro-implant related torque as a function of implant size, i.e. the diameter and length, screw size, and the bony resistance at the implant to bone interface. Methods: The resistance at the implant to cancellous bone interface $(S_{can})$ was assumed to be in the range of 1.0-2.5 MPa. Micro-implant model of Absoanchor (Dentos Inc. Daegu, Korea) was used in the course of the analysis. Results: The results showed that the torque was a strong function of diameter, length, and the screw height. As the diameter increased and as the screw size decreased, the torque index decreased. However the strength index was a different function of the implant and bone factors. The whole Absoanchor implant models were within the safe region when the resistance at the implant/cancellous bone $(=S_{can})$ was 1.0 or less. Conclusion: For bone with $S_{can}$ of 1.5 MPa, the cervical diameter should be greater than 1.5 mm if micro-implant models of 12 mm long are to be placed. For $S_{can}$ of 2.0 MPa, micro-implant models of larger cervical diameter than 1.5 mm were found to be safe only if the endosseous length was less than 8 mm.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.4
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• pp.229-236
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• 2003

This pot experiment was conducted in order to observe the effects of application of combined micronutrients(T$_1$: control. T$_2$; Fe, T$_3$; Fe+Mn, T$_4$； Fe＋Mn＋Cu, T$_{5}$; Fe+Mn+Cu＋Zn, T$_{6}$；Fe+Mn+Cu＋Zn+Mo, T$_{7}$； Fe+Mn+Cu+Zn+Mo+B) on forage performance of pure and mixed cultures of orchardgrass and white clover. The first part was concerned with the changes in the growth, summer depression, and flowering of forage plants. The results obtained are summarized as follows: 1. The T$_3$and T$_{6}$ resulted in a wide chlorosis induced by the Fe-deficiency on orchardgrass. Chlorosis was significantly reduced by the T$_4$and T$_{5}$, whereas the T$_{7}$, T$_2$, and T$_1$showed normal growth without chlorosis symptoms. The T$_{7}$ resulted in the best growth of orchardgrass both in the pure and mixed swards. There was no chlorosis symptom on white clover. whereas the T$_1$, T$_2$and T$_{7}$ showed a relatively good growth with deep green leaf-colour compared with the other treatments in the pure culture. 2. In summer, a summer depression occurred in orchardgrass: this was significantly reduced by the T$_1$and T$_{7}$. The treatments with chlorosis symptoms in orchardgrass partly induced a lodging. Summer depression in white clover did not occur. 3. In the pure culture, the T$_{7}$ and T$_2$in white clover resulted in many flowers and flower-buds compared with the other treatments. The T$_{7}$, especially, showed a long blooming period and an early full bloom compared with the other treatments, whereas the T$_{6}$ and is showed inferior numbers of them. Only the T$_{7}$ resulted in more flowers than flower-buds, and above 1 in the flower/flower-bud ratio except the T$_{6}$ in the mixed culture. 4. It was recognized that the chlorosis of Fe-deficiency occurred not only from the unsuitable ratios of Fe/Mn and Fe/Mo but also from the unsuitable mutual ratios among the cations(Fe, Mn, Cu and Mn), between the anions(Mo and B), and their total ion concentration. It was observed the multiple interactions of Fe${\times}$Mn${\times}$Mo${\times}$B, and the distinct role of B as a regulator.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.3
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• pp.274-282
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• 1992

Annual forage crops have been increasingly important for conpensating insufficient forage production of perennial pastures took place for short interval. This experiment was conducted to determine the effect of sward composition and NㆍP fertilization on forage production and intercompetition of subterranean clover-Italian ryegrass and berseem clover-Italian ryegrass. The two clovers were grown in the field at the clover/ryegrass ratios of 0/100, 25/75, 50/50, 75/25 and 100/0 where no, N (200 kg /ha), P (50 kg /ha) or NㆍP fertilization was done. Each crop was separated after harvest and drying. Relative Crowding Coefficient (RCC), aggressivity and Relative Yield Total (RYT) were analyzed on the basis of the harvested dry matter of each crop. Berseem clover-ryegrass mixtures produced greater yield than subclover-ryegrass mixtures as a result of higher yields of the two component species. In the former forage yield was increased with increased rate of clover up to 75%, while in the latter the highest yields were obtained at more than 50% of the clover. In the mixtures N stimulated the growth of ryegrass, whereas P did only that of subclover. The two clovers produced more forage than the companion grass under no and only P fertilization although the reverse result was true under N or NㆍP fertilization, but the annual forage yield was decreased in the order of N and P, N, P, and no fertilization. The mixture yields were overyielded compared to the Expected Yield. Although generally RCCs and RYTs of subclover were higher than those of berseem clover in the mixtures differing the composition rate or under no and only P fertilization, those of the former clover were lower under N or NㆍP fertilization. In the clover-ryegrass mixtures, ryegrass acted as an aggressor and became more aggressive under P fertilization.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.2
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• pp.147-154
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• 1996

Rye(Secale cereale L.) shows lower dry matter yield and nutrient content when it was harvested before wintering. This study was conducted to investigate how effect forage rape(Brassicu napus Subsp oleifera), which carries early maturity and can be harvested before wintering, on the increase of the forage yield and nutrient content when rye was sown mixed with the rape. Optimum sowing rate of the rye/rape mixture was also pursued in this study. The five treatment of rye single, rape single, ryel20+rape 1Okg/ha, rye84+rape 7kg/ha and rye60+rape 5kg/ha were sown on 2 September 1989. Rape single plot was cut one time(l9 November 1989) and the other plots were cuted two times(19 November 1989 and 20 May 1990). In botanical composition of the mixtures, rape recorded dominant ratio with 64~69% at the autumn cut. The rye84+rape 7kg/ha mixture plot marked the highest dry matter yield with 4.46t/ha among all the experimental plot at the autumn cut(P<0.05). In year total yield of dry matter(t/ha), rye single, rape single, rye120+rape IOkg/ha, rye84+rape 7kg/ha and rye60+rape 5kg/ha marked 13.6, 4.1, 12.7, 12.9 and 11.8, respectively. In crude protein content, the rye single plot was 17.2% at the autumn cut on the other hand the mixture plots showed increasing tendency with 18.0~19.9%. In crude fiber content, the mixture plots were remarkably lower than rye single plot. In year total yield of crude protein, rye84+rape 7kg/ha mixture plot showed the highest yield with 1.6lt/ha among all the experimental plots. Ratio of crude protein yield to crude fiber yield, rye84+rape 7kg/ha tended to be higher than the other mixture plots. It is confirmed that the rye/rape mixture can produce more forage than the rye single cropping when they are harvested in late autumn, besides the mixture forage contains higher crude protein than that rye single forage. It can be said that the rydrape mixture is more useful than the rye single cropping, and optimum sowing rate of the mixture is 84kg/ha of rye+7kg/ha of rape.