• Asian-Australasian Journal of Animal Sciences
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• v.22 no.7
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• pp.923-930
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• 2009

This study was conducted to compare three models: two random regression models with and without considering heterogeneity in the residual variances and a lactation model (LM) for evaluating the genetic ability of Holstein cows in Korea. Two datasets were prepared for this study. To apply the test-day random regression model, 94,390 test-day records were prepared from 15,263 cows. The second data set consisted of 14,704 lactation records covering milk production over 305 days. Raw milk yield and composition data were collected from 1998 to 2002 by the National Agricultural Cooperative Federation' dairy cattle improvement center by way of its milk testing program, which is nationally based. The pedigree information for this analysis was collected by the Korean Animal Improvement Association. The random regression models (RRMs) are single-trait animal models that consider each lactation record as an independent trait. Estimates of covariance were assumed to be different ones. In order to consider heterogeneity of residual variance in the analysis, test-days were classified into 29 classes. By considering heterogeneity of residual variance, variation for lactation performance in the early lactation classes was higher than during the middle classes and variance was lower in the late lactation classes than in the other two classes. This may be due to feeding management system and physiological properties of Holstein cows in Korea. Over classes e6 to e26 (covering 61 to 270 DIM), there was little change in residual variance, suggesting that a model with homogeneity of variance be used restricting the data to these days only. Estimates of heritability for milk yield ranged from 0.154 to 0.455, for which the estimates were variable depending on different lactation periods. Most of the heritabilities for milk yield using the RRM were higher than in the lactation model, and the estimate of genetic variance of milk yield was lower in the late lactation period than in the early or middle periods.

• Journal of Korea Foresty Energy
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• v.1 no.2
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• pp.1-19
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• 1981

In order to investigate biomass yield of one-year-old hyblrid poplars, Pripulusalba x P. glandulosa $F_1$ and Populus nigra var. italica x P. maximowiczii $F_1$clones, as energy and fiber resources, dry matter yield, leaf area, leaf area index, dry matter production ability, specific gravity and fiber length and width were measured. Dry matter yield was 1.89 ton/ha for Poplus alba x P. glandulosa $F_1$ and 3.63 ton/ha for Populus nigra via.italica x P. merximowiczii $F_1$ clones in the planting density of 20,000 trees/ha and in the planting density of 40,000 trees/ha was 3.87 ton/ha for Populus alba x P. glandulosa $F_1$and 5.64 ton/ha for Populus nigra var. italica x P. maximowiczii $F_1$ clones. Leaf area index was 1.24mtim2 in the planting density of 20,000 trees/ha and 2.45 m31m3 in the density of 40,000 trees/ha for Populus alba x P. glandulosa $F_1$ clones and it was 1.96 m21m2 in the planting density of 20,000 trees/ha and 3.36 m21m2 in the density of 40,000 trees/ha for the hybrid $F_1$ Populus nigra var. italica x P. maximowiczii clones. The average specific gravity of the hybrid poplars was 0..36 when bark and pith were included and 0.31 when bark and pith were removed in the plot of 20,000 trees/ha and in the 40,000 trees/ha plot showed 0.35 and 0.31 respectively, for Populus alba x P. glandulosa $F_1$clones. It was 0.36 when bark and pith were included and 0.32 when bark and pith were removed in the 20,000 trees/ha plot and in the 40,000 trees/ha plot was 0.34 and 0.31 respectively for Populus nigra var. italica x P. maximowiczii $F_1$clones. The average fiber length was 0.57 mm in the 20,000 trees/ha plot and 0.58 mm in the 40,000 trees/ha plot for Poplus alba x P. glandulosa $F_1$clones and was 0.60 in both plots of 20,000 trees/ha and 40,000 trees/ha for Populus nigra var. italica x P. maximowiczii $F_1$ clones. There is a big clonal variation among those clones studied, showing high selection potential in both species.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.5
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• pp.449-460
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• 1992

The main purpose of these studies was to obtain the basic informations necessary to develop soybean varieties. Two determinate soybean varieties, Hwangkeumkong and Jangyeobkong, and two indeterminate varieties, Clark and Williams were used to study the differences in growth and yield characters. Indeterminate varieties showed 30 days longer in days from intial flowering to terminal leaf stage and increased 7-8 more nodes on mainstem after initial flowering than determinate varieties. Determinate varieties were greater at middle-upper part, while indeterminate varieties were greater in middle part for the dry weight of the pods and stem at maturity. Total dry weight per unit area was greater in determinate varieties than in indeterminate ones from the early growth to maturity. However, the duration of vegetative growth was longer and the ability to keep leaf area index in the late growth stage was higher in indeterminate varieties. Variations among plants were greater in the order of branch related characters > mainstem, total vegetative, and yield related characters > morphological characters of mains tern and 100 seed weight. In general, variations of vegetative characters formed in the early growth stage were greater than those of yield characters formed in the late growth stage. On the other hand, the variations of those characters were greater in indeterminate varieties than in determinate ones. Variation of a seed weight within a plant was much smaller in determinate varieties than in indeterminate ones : i.e. coefficients of variation of a seed weight within a plant were from 13.6 to 13.8% in determinate varieties and were from 18.5 to 21.1% in indeterminate varieties, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.2
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• pp.127-133
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• 1989

An experiment was conducted at the Yeongnam Crop Experiment Station to obtain basic informations about cultural techniques for high yield by manipulating plant spacing in association with seedling number. Cultivars showing relatively low competition index within or between rice hill were Palgongbyeo, Milyang 83. Milyang 90 and Sangpungbyeo, while those with high competition index were Pungsanbyeo, Samgangbyeo, Weongpungbyeo, Taebaegbyeo and Dongjinbyeo. Variations of agronomic characters such as culm length, spikelets per panicle, grain yield per panicle among each culm within hill were not interrelated among the characters. This phenomenon was also same within and between cultivar groups. However, cultivars having high competitive ability showed relatively low variation in agronomic characters. There was a trend that most of rice cultivars had a high positive correlation between total competition index and rice grain yield. Competition index between rice hill was more significant than that of within rice hill for Tongil type cultivars except Milyang 83 which belonged to low tillering capacity while both types of competition index within and between hill were important for Japonica type cultivars and Milyang 83 of Tongil type cultivar to increase rice yield.

• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.341-356
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• 1975

This study was carried out to evaluate three winter active synthetic varieties in a succeeding generations of improvement and polycross progenies of seven genotypes selected at the cool and wet climate of the Western Oregon, in their performance of the polycross progeny test comparing with a control variety, high yielding 'Fawn', at Daejon, Korea. Various plant and leaf characteristics, especially related to photosynthesis, and forage production during the first summer after the establishment were examined. The important conclusions of this study are summarized as follows: 1. The differences of leaf fresh weight among groups and control exhibit genetic differences. The a verage of leaf fresh weight of polycross progeny group was the heaviest and those of winter active synthetic varieties in the succeeding generations of improvement was heavier than variety 'fawn'. Within polycross progeny group the genotypes exhibit genetic differences for leaf dry weight. 2. The leaf area exhibited genetic differences among groups and control. The average of winter active synthetic varieties in a succeeding generation was larger than variety 'Fawn'. Those oi the polycross progeny group was the largest among groups and control. 3. Differences of specific leaf weight(S. L. W.) among and within varieties, genotypes and control were not significant. Further investigation in this respect is necessary through the study of the diurnal change in S. L. W. 4. Differences of leaf width among groups and control exhibited genetic differences. The average leaf width of winter active varieties was larger than those of 'Fawn' variety. And those of polycross progenies of genotypes was the largest. 5. Plant height of 'fawn' variety in the first measurement was higher than those of winter active tall fescue varieties and genotypes. The deviation in plant height among polyeross progenies of seven genotypes gave a great deviation. The regrowth ability of plant height was not different suggesting that this characteristics was about the same among and within groups and control. 6. Plant width, spreading ability, improved through the succeeding generations of the improvement of the winter active synthetic varieties for the first measurement. Differences of plant width at the second measurement among genotypes within polycross progeny group were big enough to show the genetic difference. 7. Tiller number of the winter active synthetic varieties and the average of genotypes in polycross progeny was more than those of the control 'Fawn' in the first measurement. On the second measurement, the differences of tiller number appeared among three synthetic varieties indicating improvement, and there were genetic differences among seven genotypes in polycross progeny test. 8. Forage yield on the first cutting showed a considerble improvement of forage yield in the more advanced generation of synthetic varieties and genetic differences among seven genotypes in the polycross progeny test. The average of polycross progeny group was higher than those of the control or three winter active varieties. It was suggested that we could make a further improvement for the forage yield. 9. The regrowth ability of these winter active varieties and genotypes was about the same capacity at least on the measurement of the regrowth in forage yield and plant height during summer. 10. On the whole, the averages of the polycross progeny group was in the highest value and those of synthetic varieties were higher than the control variety, 'Fawn', for the most characteristics except S. L. W. and the plant height on the first measurement even though the differences were not always significant. And there were genetic differences among seven gentypes in their performance of the polycross progeny. 11. Although it was not always sgnificant, the most advanced winter active variety, '1002', had in the highest value for all plant characteristics and forage yield measurements than the other two varieties, '1001'. 12. The results of the association study among various characteristics were quite agreeable and would be useful in the selection of desirable genotypes for the development of a better variety.

• Korean Journal of Weed Science
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• v.2 no.1
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• pp.7-12
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• 1982

The experiment was studied to know the competitive ability of rice against weeds as affected by rice maturity and plant spacing. For both cultivars, Tongil (12 days later) and Yeongnamjosaeng, the least amount of weed was obtained from the 10 ${\times}$ 10cm plant spacing while no difference between 40 ${\times}$ (10 ${\times}$ 10cm) and 30 ${\times}$ 15cm plant spacings was observed. When weed was nor pulled out by hand, significant yield loss was resulted in 30 ${\times}$ 15cm and 40 ${\times}$ (10 ${\times}$ 10cm) plant spacings while no difference between weeding regime was observed at the 10 ${\times}$ 10cm plant spacing in both cultivars. Rice grain yield was unaffected by plant spacing for hand weeded plot in both rice cultivars. For noweeding plot, however, the highest grain yield was obtained from 10 ${\times}$10cm plant spacing and also this yield was not significantly different from the yield of hand weeded plot while significant yield loss was recognized at the 30 ${\times}$ 15cm and 40 ${\times}$ (10 ${\times}$ 10cm) plant spacings in noweeding plot. There was also a good relationship between weed weight and grain yield for both cultivars (Tongil; Y = 5.68 - 0.0127 X, r = -0.814$^*$; Yeongnamjosaengv Y = 5.04 - 0.0314 X, r =-0.9704$^{**}$). Based on these relationship, weed weight of 188.2g/sq.m for Yeongnamjosaeng and 223.6g/sq.m for Tongil was needed to reduce rice yield by 50%, respectively. This result implied that Tongil compete more efficiently against weed than Yeongnamjosaeng and hence, could be concluded that late maturing cultivar was more competitive against weed compared to early maturing cultivar.

• Korean Journal of Organic Agriculture
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• v.15 no.1
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• pp.59-69
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• 2007

This experiment was conducted to study the spring productivity and feeding value of hairy vetch varieties. We also measured DM yield and feeding value by analyze CP and CF that authors made possible to calculate TDN and RFV. The results can be summarized as follows; Dry matter yield were increased earlier autumn seeding date and later cut in spring. Differences of dry matter yield in earlier cut in spring was high in order of Ostsaat, Welta, Vv4712, Penn-02, Common and Minnie. Crude protein(CP) yield was increased when earlier autumn seeding date and later cut in spring. Total digestible nutrient(TDN) yield of hairy vetch varieties was decreased when later autumn seeding date, and was increased when later cut in spring. TDN yield was highest in Ostsaat and Welta varieties had highest dry matter yield. Acid detergent fiber(ADF) content was decreased when later autumn seeding date and was increased when later cut in spring. Neutral detergent fiber(NDF) content was decreased when later autumn seeding date. Average values for relative feed value(RFV) were 157% and 132% in both cut. It shows that a high feed value in all of hairy vetch varieties. Above all, the results presented that the optimal seeding date for cultivating hairy vetch in the central region of Korea is between the 10th to the 20th of September. Because Ostsaat and Welta had significantly high dry matter yield we expected Ostsaat and Welta have a higher wintering ability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1571-1577
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• 2007

The herb mixtures that are known to lower blood pressure were selected through oriental medical books and prescriptions and the physicochemical properties of their water extracts were analyzed to examine the possibility as functional food materials. The total yield of 28 water extracts was in the range of $5.33{\sim}36.71%$. Total phenolics and flavonoid content were $204.89{\sim}2543.29mg%\;and\;59.79{\sim}1430.55mg%$, respectively, and especially No. 2, 5, 9, 17, 18, 20, 22, and 26 showed high rates of above 800 mg%. Electron donating ability (EDA) was $7.81{\sim}98.18%$, and the samples that showed high values in EDA were similar to the samples with high values in total phenolics and flavonoid content. Phenolics and flavonoid compounds of the herbs are considered to perform a major role in antioxidation. Nitrite scavenging ability reached the highest at pH 1.2 ($11.70{\sim}96.47%$) and the lowest at pH 6.0 (below 12.77%), which indicates that nitrite scavenging ability decreases when pH increases.

• Food Science and Preservation
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• v.24 no.8
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• pp.1113-1121
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• 2017

The purpose of this study was to determine antioxidant and physiological activities of water and 70% ethanol extracts from Ligularia fischeri by extraction methods. The yield of water and ethanol extracts from Ligularia fischeri was 15.23% and 17.45%, respectively. The polyphenol and flavonoid contents of ethanol extracts of Ligularia fischeri (LEE) were $17.17{\pm}4.38mg/g$, $35.06{\pm}6.69mg/g$, respectively. The electron donating ability and SOD like activity, and ABTS radical ability of all Ligularia fischeri extracts were increased in a dose dependent manner, and those was the highest in LEE. Nitrite scavenging ability was higher in pH 1.2 than that in pH 3.0, and ethanol extract showed higher ability in pH 1.2 and 3.0. The xanthine oxidase and inhibition effect of all Ligularia fischeri extracts on tyrosinase were dose-dependently increased, and those was the highest in ethanol extracts of Ligularia fischeri. Reducing power was 1.2 at extract concentration $1,000{\mu}g/mL$ in water and ethanol extracts of Ligularia fischeri and the highest in water extract of Ligularia fischeri at concentration of $62.5-500{\mu}g/mL$. These results may contribute to development of processed food and health functional food with Ligularia fischeri.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.131-136
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• 1985

This experiment was conducted to identify the competitive ability of rice against Monochoria vaginalis Presl. and to determine effect of various herbicides on it. Photosynthetic efficiency of rice markedly increased as the density of M. vaginalis increased from 1 to 3 plants per hill. Competition index increased in propotional to an increase of M. vaginalis density while total dry matter of rice decreased in reverse. Significant yield reduction of rice, was observed at the density of M. vaginalis, 2 plants per hill and 37% at 3 plants per hill. Such a yield reduction can be mainly attributed to the decrease of panicle and spikelet number of rice which were greatly affected by competition with M. vaginalis. Regardless of herbicides tested, % inhibition increased remarkably as the concentration of herbicides increased from 1 to 20 ppm. No plant growth was observed in all the herbicides treated with 20 ppm except for butachlor, thiobencarb and bifenox, showing existence of the new promising herbicides to control M. vaginalis among the herbicides tested.