• Korean Journal of Agricultural Science
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• v.1 no.1
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• pp.9-26
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• 1974

1. Results in Nursery This experiment was carried out on the effect of the seed treament, soil preparations, kinds of covering soil and inside covering methods in two rice varieties, 'Tongil' and 'Akibare' to find out the most reasonable model of the flat nursery bed, with which lower cost is required comparing with the tunnel nursery. The results obtained are as follows: (1) The seedling of all plots of the ordinary seed were very poor compared to the plots of sprouted seed. (2) In case that the variety 'Tongil' was cultivated on the dry nursery bed, the good seedling percentage and the plant height rat io were significantly increased but the other characteristics of the seedling were not noticeable. (3) The kinds of the covering soil had not an effect on the seedling growth significantly. (4) Inside straw mulching was seemed effective for the protection in the case of the extreme high temperature and heavy rain fall, even though there was not significant differences between inside straw mulching and no treatments at the flat type nursery. (5) Difference of seedling growth between the flat type nursery and the tunnel type nursery was not significant. And it's reason was thought that the covering period of polyethylene film was short in semi hot nursery for the common early transplanting cultivation of rice. (6) The percentage of good seedling was higher at 'Akibare' than 'Tongil', variety but the number of seedling leaf and the seedling growth ratio in height were significantly increased in the variety 'Tongil'. The other seedling characters between there two varieties were not significantly different. 2. Results after transplanting This experiment was conducted to study on the ripening percentage, rice yield and disease, appearance of the seedling from sprouted seed plots including common irrigated nursery as check plot after transplantnig. The results obtained are summarized as follows: (1) The rice yield, the yield components and the appearance of leaf discoloration of both varieties, 'Tongil' and 'Akibare' were slightly betterat the plot of the standard tunnel nursery than that of the flat nursery with inside mulching or the among these three plots. (2) For 'Tongil' variety, the ripening percentage and the rice yield were significantly decreased at the common irrigated nursery compared with semi hot nursery. (3) The ripening percentage and the rice yield of 'Akibare' contrasted with 'Tongil' were significantly decreased at thesemi 'hot-nursery compared with common irrigated nursery. The main reason was thought to be the injury of the rice stripe disease (Rice stripe disease virus). Considering above mentioned experimental result, the seedling of 'Tongil' must be cultivated on the semi bot nursery for better ripening percentage as well as rice yield and for prevention of red discoloration. And as a model of semi hot nursery, the polyethylene covering nursery of standard tunnel type is most desirable but that of flat type with inside straw mulching is thought to be desirable too.

• Korean Journal of Agricultural Science
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• v.17 no.1
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• pp.1-8
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• 1990

The paper board sludge(PBS) itself and compost sludge manure(CSM) mixed with sawdust, fowl droppings and urea to the PBS were treated to soybean plants to find the effects of growing characters, yield components, and nutritional compounds in the plant tissues. 1. Percentages of missing plants were 5-9% and 3.6-4.1% in the treatments of PBS and CSM, respectively. After that, the plants were restored to normal conditions. Anyway it is not desirable to use the paper board sludge and immature compost sludge manure in seeding time or to young seedlings. 2. Growth of the plant height was retarded in early growing phase, but it was normal in later stages. And the width and length of the largest leaf, numbers of main stem nodes and pods were not significant among the treatments. 3. The yield intends to increase through the treatments of 1,200, 1,600, and 2,000Kg PBS per 10a. In the CSM treatments with high rate of sawdust, fowl droppings and urea, the numbers of pods and grains were higher than the treatment of high content of PBS. 100-grain and one liter weights were opposite intention. It was suggested that the excess nitrogen amounts from the compost sludge manure than conventional fertilization affected to the yield components. 4. The contents of the main chemical compounds such as N, $P_2O_5$, $K_2O$, Ca, Mg were determined. The concentrations of nitrogen were higher in the treatment of PBS and CSM than none and control. 5. In conclusion, the nutritional effects of PBS were in evidence. To use the sludges, it should be fermented with adequate additives to improve the aeration, C/N ratio, activity of microbial, and other conditions. The sludges could be used to crops as a fertilizers effectively.

• Korean Journal of Agricultural Science
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• v.1 no.1
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• pp.91-116
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• 1974

Taiwan agricultural development in the last decade has not been changed much since the accomplishment of land reform program. This is mainly due to the rapid development taken place within industry that agricultural development can not keep pace with. The increasing gap of rural-urban income discrepancy has caused socio-psychological unstability among rural people and inspire wants of out-migration. From 1961 to 1970, population of the ten largest cities showed an annual growth rate of 4.05%, while the population of the remainder of Taiwan showed 2.06%. Assuming the natural increase rate of these two population sections are similar, the difference of rural and urban annual growth rate can be at tributed to the flow of people from rural to urban sectors. The main objective of this paper is to identify the amount of agricultural out-migration and its impact on agricultural development and agricultural extension programs. Specifically, the objectives are to examine (1) rural-urban population composition (2) rural out-migration estimation (3) changes of agricultural population, and (4) implications for agricultural development and extension programs Some of the important findings are listed below; (1) The average agricultural out migration of the period 1960-1969 is estimated at around 60,000 per year. Take Tainan prefecture for example, the Male-Female Migration Ratio is 0.39 for age 20-24, 0.55 for age 25-29, 0.90 for 30-34. It is understood between age 20 and 34, the rural female migration rate is higher than the rural male. (2) Based on the population growth rate of 1950-1969, agricultural population is projected for the period of 1953 to 1989. By 1978, the agricultural population will reach its peak and begin to dedaine from 1980. The projected agricultural population in 1989 is 5,847,566 which occupies 29% of the Taiwan total population. (3) Assuming area of cultivated land keep unchanged as 905,263 ha. in 1970, and tif we can eliminate all 72% of part-time farms, then the average farm acreage for hose full-time farms will be increased to 3.6 hactares. This is unlikely to happen before 1989 without the government interference. (4) Less than 10% of adult farmer s of age 25-64 in 1969 enrolled in Farm Discussion Club, only 5% of adult farm women enrolled in Home Economics Club, and 5% of rural youth enrolled in 4-H Club. These statistics show a fact that only few farmers are reached by extension workers. Based on findings in this paper, some important suggestions are listed for future agricultural development. (1) Improve agricultural structure by decreasing agricultural population (a) Encourage farmers with less than 0.5 ha. of land to seek jobs outside of agriculture (b) Encourage joint cultivation and farm mechanization (c) Discourage rural migrants to Keep farm land (d) Provide occupational guidance program through extension education programs (2) Establish future farmers settlement project to assure rural youth have enough resources for farming. (3) An optimum Population policy should be integrated into rural socio-economic development and national development programs.

• Korean Journal of Agricultural Science
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• v.3 no.1
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• pp.105-119
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• 1976

Sucrose, glucose, starches hydrolyzates and raw starchy materials hydrolyzates were caramelized using various catalysis and the caramel products were analysed, in order to carry out the basic research for the replacement of caramel coloring. The results obtained were summarized as follows. 1. The caramel which was manufactured by sucrose syrup being pH 3.5 adjusted by sulfuric acid showed strong color intensity and hue as well as good stability in the solutions of table salt, tannin and alcohol. 2. The product caramelized from sucrose syrup being pH 9.5 adjusted by sodium carbonate showed very strong color intensity and black color component, and was quite stable in alcohol solution but not in table salt and tannin solutions. 3. The caramel products made from sucrose syrup using ammonium salts of strong acid like $NH_4Cl$ and $(NH_4)_2SO_4$ as catalyst showed strong color intensity and black color component but hazy apparence in solution of table salt, tannin and alcohol. 4. The product caramelized from glucose syrup being pH 9.5 adjusted by sodium carbonate indicated strong color intensity but weak red color component and was transparent in solution of table salt and alcohol but hazy in tannin solution. 5. In glucose caramel using $NH_4Cl$, $(NH_4)_2SO_4$, $(NH_4)_2CO_3$ and $(NH_4)_2SO_3$ as catalyst, $NH_4Cl$ plot was very weak in color intensity and insufficient in red color component but stable in solution of table salt, tannin and alcohol. In the case of $(NH_4)_2CO_3$, $(NH_4)_2SO_4$ and $(NH_4)_2SO_3$ plots, all products were strong in color intensity but little insufficient in red color component. On the stability in solutions, $(NH_4)_2SO_3$ plot was stable in two solutions expect tannin solution, $(NH_4)_2CO_3$ plot was only stable in alcohol solution and $(NH_4)_2SO_3$ plot was only stable in table salt solution. 6. When the acid hydrolyzed starch syrups without neutralization were caramelized using $(NH_4)_2SO_4$ as catalyst, the potato starch hydrolyzate caramel showed higher in color intensity being similar to its of glucose caramel than sweet potato starch hydrolyzate caramel and corn starch hydrolyzate caramel. 7. Dried sweet potato powder, dried acorns powders, the acorns (from Q. serrata THUNB and Q. acutissima CARR.) powders extracted with water for 7 days and with 50% alcohol solution for 24 hrs were hydrolyzed by sulfuric acid in autoclave at $3.5kg/cm^2$ as pressure for 60 mins, and were caramelized using $(NH_4)_2SO_4$ as catalyst. It was supposed that all of those products were poor quality on color and stability in solutions at the viewpoint of food coloring matter.

• Korean Journal of Agricultural Science
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• v.22 no.2
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• pp.170-179
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• 1995

This study was conducted to investigate the genetic constitution of blood proteins and enzymes in 238 Korean Native cattle reared at Korean Native Cattle Breeding Center, National Livestock Cooperative Federation. The genetic polymorphisms of post-transferrin-2(pTf-2), transferrin(Tf), post-albumin(pAlb), albumin(Alb), ceruloplamin(Cp), amylase-I(Am-I) and hemoglobin(Hb) were analyzed by using PAGE(polyacrylamide gel electrophoresis) and STAGE(starch gel electrophoresis). The genotypes and gene frequencies were estimated at these loci for each blood proteins and enzymes. The results obtained from this study were summarized as follows : 1. The pTf-2 locus were identified to be genetically controlled by codominant alleles designated pTf-2 F and S, and the distribution of genotypes were 46.22, 46.64 and 7.14% for pTf-2 FF, FS and SS types, and the gene frequencies of the pTf-2 F and S allele were 0,695 and 0.305, respectiveley. 2. The Tf locus were found to be controlled by Tf A, D1, D2 and E alleles, and the distributioin of genotypes were 0.84, 13.87, 13.03, 10.92, 22.27, 12.61, 2.94, 15.51, 6.72 and 1.68% for Tf AA, AD1, AD2, AE, D1D1, D1D2, D1E, D2E and EE types, and the gene frequencies of Tf A, D1, D2 and E were 0.197, 0.430, 0.191 and 0.081, respectively. 3. The pAlb locus were observed to be controlled by two alleles, pAlb F and S, and the distribution of genotypes were 42.86, 33.19 and 23.95% for pAlb FF, FS and SS types, and the gene frequencies were 0.595 and 0.405 for Tf F and S allele, respectively. Also the gene frequencies of Alb was 1.000 of Alb A allele. 4. The Cp locus were identified to be controlled by Cp F and S allele, and the distribution of genotypes were 23.11, 34.87 and 42.02% for Cp FF, FS and SS types, and the gene frequencies were 0.405 and 0.595 for Cp F and S allele, respectively. 5. The Am-I locus were observed to be genetically controlled by Am-I B and C allele, and the distribution of genotypes were 51.26, 16.81 and 31.92% for Am-I BB, BC and CC types, and the gene frequencies of Am-I B and C alleles were 0.597 and 0.403, respectively. 6. The Hb locus were found to be controlled by Hb A and B alleles, and the distribution of genotypes were 93.19, 16.39 and 0.42% for Hb AA, AB and BB types, and the gene frequencies of Hb A and B alleles were 0.914 and 0.086, respectively.

• Korean Journal of Agricultural Science
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• v.20 no.1
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• pp.56-67
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• 1993

To applying of genetic markers of milk proteins as dairy cow registration and selection aids for genetic improvement, genopypes controlling the 4 milk protein loci, ${\alpha}S1$-casein (${\alpha}S1$-CN), ${\beta}$-casein(${\beta}$-CN), ${\kappa}$-casein(${\kappa}$-CN), and ${\beta}$-lactoglobulin(${\beta}$-LG), from a total of 159 Holstein lactating cows reared at National Animal Breeding Station in 1992 were detected by polyacrylamide gel(PAGE) electrophoresis, and associations between genetic polymorphisms of milk proteins and milk compositions were analyzed. The observed distribution of phenotypes for ${\alpha}S1$-CN, ${\beta}$-CN, ${\kappa}$-CN and ${\beta}$-LG were agreement with those expected under the assumption of genetic equilibrium. The observed genotypic frequencies of the ${\alpha}S1$-CN BB, ${\beta}$-CN AA, ${\kappa}$-CN AA and ${\beta}$-LG AB genotypes were founded to be very high as 79.87%, 84.28%, 71.70% and 49.10%, respectively. Gene frequencies were 0.899 and 0.101 for ${\alpha}S1-CN^B$ and ${\alpha}S1-CN^C$, 0.921 and 0.079 for ${\beta}-CN^A$ and ${\beta}-CN^B$, 0.837 and 0.163 for ${\kappa}-CN^A$ and ${\kappa}-CN^B$, 0.378 and 0.622 for ${\beta}-LG^A$ and ${\beta}-CN^B$. According to the results of analysis of variance, the genotypes of the ${\alpha}S1-CN$, ${\beta}-CN$, ${\kappa}-CN$ and ${\beta}-LG$ were significantly difference for fat, protein and total solid percentage in milk compositions. On milk compositions, the ${\kappa}$-CN BB genotype was very high fat and protein percentage more than ${\kappa}$-CN AA and AB genotypes, and ${\beta}$-LG AA genotype was very high fat percentage more than ${\beta}$-LG AB and BB genotype at 5% level of significant difference, respectively. As a consequence, the fat and protein percentage may be improved to select to ${\kappa}$-CN BB and ${\beta}$-LG AA genotypes.

• Korean Journal of Agricultural Science
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• v.12 no.1
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• pp.1-16
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• 1985

This experiment was conducted to study sex expression and subsequent changes in protein and peroxidase after three cultivars of cucumber plants were treated with ethephon and gibberellin. The three cultivars of cucumber used in this study included 'Sayeup' (monoecious type), 'Sinrokdadaki' (gynoecious type), and 'Seonghowon' (intermediate type). The ethephon at 250 ppm and gibberellin at 100 ppm were treated at the 2-leaf and 4-leaf stages, and subsequent sex expression and changes in protein contents, peroxidase activities and isoperoxidase banding patterns by disc polyacrylamide gel electrophoresis were studied. The results can be summarized as follows: 1. Ethephon treatment slightly increased number of pistillate flowers and significantly decreased number of staminate flowers in the three cultivars, while gibberellin treatment significantly increased number of staminate flowers in both gynoecious 'Sinrokdadaki' and intermediate 'Seonghowon' and did not increase number of staminate flowers in monecious 'Sayeup' 2. There were some differences among three cultivars in protein contents, protein banding and isoperoxidase banding patterns of seeds and germinating seeds. However, it was not obvious to differentiate monoecious from gynoecious cultlvars by these characters. 3. Protein contents in the leaves. and stem apex after ethephon and gibberellin treatment increased gradually at the 2-leaf stage, but decreased at the 4-leaf stage. Protein contents in stem apex at the 4-leaf stage without treatment were much higher in 'Sinrokdadaki' and 'Seonghowon' than in monoecious 'Sayeup'. Protein contents in the stern apex at the 4-leaf stage were increased in the ethephon-treated monoecious 'Sayeup' and decreased in 'Sinrokdadaki' and 'Seonghowon' compared with untreated plants. 4. Peroxidase activities in the leaves and stem apex gradually decreased at the 2- leaf stage, but increased at the 4-leaf stage. Peroxidase activities in stern apex at the 4-leaf stage were significantly increased by ethephon treatment. 5. The number of protein bands in the three cuitivars after treatment gradually decreased in leaves and stem apex at the 2-leaf stage, but increased in the 4-leaf stage. The protein banding pat terns of stern apex of the ethephon-treated monoecious 'Sayeup' at the 4-leaf stage were gradually shifted to the banding.

• Korean Journal of Agricultural Science
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• v.4 no.1
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• pp.10-20
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• 1977

An expriment was conducted to determine the rate of germination under low temperature and effects of low temperature on seedling of varieties derived from the cross between Indica and Japonica type of rice. Total of 30 varieties including leading variety, Tongil, were germinated at the temperature of $10^{\circ}C$. and $15^{\circ}C$. to determine the rate of germination, and six varieties also including Tongil were planted in pot, and seedlings were exposed to the temperature of $5^{\circ}C$. and $1^{\circ}C$. for 15 days and damage of plant growth due to low temperature was observed. 1. Under the condition of $10^{\circ}C$., varieties such as Iri #323, Suwon #253, Iri #325, Milyang #22, Suwon #251, and Suwon #267 were showing over 70 percent of germination ratio, while varieties, Dodolokiwase, Milyang #23, Yusin, Iri #328, and Iri #329 were below 10 percent in germination ratio. 2. Under the condition of $15^{\circ}C$., variety Suwon #262 was shown 100 percent of germination and varieties such as Milyg an#22, Dodlokiwase, Tongil, Milyang #29, Suwon #258, Milyang #23, Milyang #24, Milyang #28 and Milyang #21 were over 90 percent in germination ratio. However, varieties such as Iri #328, Iri #329, Jinheung, and Minehikari were below 50 percent in germination rate. 3. Considering the germination rate and average days required to germination, Milyang #22 and Iri #323 were highly resistant varieties to low temperature. The rate of germination of varieties from the cross between Indica and Japonica under low temperature was not always lower than that of varieties from Japonica type of rice. 4. Most of the seedlings of varieties used were quite resistant to $1^{\circ}C$. at least for six hours. However, leaves of rice were exposed to the the temperature of $1^{\circ}C$. for 12 hours, and the withered leaves were recovered soon when put in under normal temperature. The degree of leaf withering under low temperature was lower in Milyang #15, Japonica type than in varietieties belonging to $Indica{\times}Japonica$ type of rice. 5. When the seedlings of varieties such as Josaengtongil, Tongil and Yusin were exposed to the temperature of $1^{\circ}C$. for 36 hours, 70 percent of leaves were withered and when the time of expose were doubled, the leaves were completely died. When the temperature was fluctuated, over 75 percent of leaves were died, while 65 percent of leaves of Milyang #15 were died when exposed to $1^{\circ}C$, for 72 hours. 6. Significant growth retardation was observed for all entries when exposed to $1^{\circ}C$. for 24 to 36 hours. The growth retardation was apparently increased as the time of expose was extended.

• Korean Journal of Agricultural Science
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• v.4 no.1
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• pp.94-104
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• 1977

In order to investigate the effects of mechanical transplanting on the rice, four rice varieties including Jo-saing Tongil were planted in case nursering bed for three times with 10 days interval beginning from April 16. Fourty days old seedlings were transplanted with rice-transplanter, and growth habits of seedlings in bed and rice plants in main field and yield were examined and summerized as follows: 1. The plant height and number of leaves of the 40 days old seedling in case nursery bed were appeared to be less than those of seedlings grown in ordinary nursery bed. In case nursery, the plant height and number of leaves of seedlings grown in case nursery were apparently higher than those of seedlings grown in upland case nursery. 2. The root of 40 days old seedlings were cut to investigate the rooting ability of seedlings, and the rooting ability of the seedlings grown in the case nursery bed were apparently lower in the rooting ability compared with the seedlings grown in ordinary nursery bed. The rooting ability of the seedlings grown in the lowland case nursery was higher than that of the seedlings grown in the upland case nursery. 3. The tip of leaves of the varieties derived from Indica type were becoming yellow and yellow-red in color 25 to 30 days after planted in the case nursery bed. Those varieties was almost stopped growth. 4. The seedlings transplanted by transplanter had shown more than five to seven days of delay in rooting, compared with the seedlings transplanted by ordinary method. The heading dates was delayed five to seven days when transplanter was used, even though the delay of heading dates was a little different depending on the varieties. 5. The yields of unhulled rice were a little lower than that of Yusin variety which was hand planted. When mechanically transplanted, the yield of Tongil variety was highest in the plot where seedlings were transplanted on May 26. When transplanted on June 15, Milyang#15 was highest in yield, indicating the importance of varietal selection in mechanical transplantation. 6. The rice transplanter could transplant from 73 to 108 seedlings per $3.3m^2$. If the seeds of rice were evenly planted in the bed, the two-row rice transplanter could be used five to six times more effectively with less than one percent of missing plant compared with the hand transplanting. This suggests that rice transplanter could be utilized in the mono cropping area. 7. Since the time of transplantings in the double-cropping area is rather limitted, mechanical transplantation might be possible without reducings yield providing better adapted varieties and improved case-nursery techniques.

• Korean Journal of Agricultural Science
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• v.25 no.2
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• pp.216-224
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• 1998

This study was performed to offer the basic and applicable data for improvement of Korean cattle and dairy cattle, according to finding the genetic construction obtained from analysis of genetic polymorphisms of ${\beta}$-lactoglobulin and ${\kappa}$-casein loci related Korean cattle and Holstein cows using PCR-RFLP. Genomic DNA used in this study was prepared from the blood of 253 individuals of Korean cattle in Korean Native Cattle Improvement Center, NLCF, and the blood of 113 individuals of Holstein cows in National Livestock Research Institute. The results obtained are summarized as follows : 1. This study confirmed amplified products of 530bp and 262bp fragments obtained from the amplification of ${\beta}$-lactoglobulin and ${\kappa}$-casein loci in Korean cattle and Holstein breed by PCR. 2. The ${\beta}$-lactoglobulin AA genotype showed 153bp and 109bp fragments, and ${\beta}$-lactoglobulin AB genotype showed 153bp, 109bp, 79bp and 74bp fragments, and BB genotype showed 109bp, 79bp and 74bp fragments in amplified products of ${\beta}$-lactoglobulin loci with the restricted enzyme digestion of Hae III. 3. The ${\kappa}$-casein AA genotype showed a 530bp fragment, and ${\kappa}$-casein AB genotype showed 530bp, 344bp and 186bp fragments, and BB genotype showed 344bp and 186bp fragments in amplified products of ${\kappa}$-casein loci with the restricted enzyme digestion of Taq I. 4. On ${\beta}$-lactoglobulin genotypes and gene frequencies, Korean cattle were 6.72%, 26.09% and 67.19% for AA, AB and BB genotypes, and ${\beta}$-lactoglobulin A and B alleles were 0.197 and 0.803, and Holstein were 35.40%, 56.64% and 7.96% for AA, AB and BB genotypes, and ${\beta}$-lactoglobulin A and B alleles were 0.637 and 0.363, respectively. 5. On ${\kappa}$-casein genotypes and gene frequencies, Korean cattle were 46.25%, 39.13% and 14.62% for AA, AB and BB genotypes, and ${\kappa}$-casein A and B alleles were 0.658 and 0.342, and Holstein were 60.18% and 38.94% and 0.88% for AA, AB and BB genotypes, and ${\kappa}$-casein A and B alleles were 0.796 and 0.204, respectively. 6. As a consequence, the gene frequency was 0.197 and 0.803 for ${\beta}$-lactoglobulin A and B alleles, and 0.658 and 0.342 for ${\kappa}$-casein A and B alleles in Korea cattle, but was 0.637 and 0.363 for ${\beta}$-lactoglobulin A and B alleles, and 0.796 and 0.204 for ${\kappa}$-casein A and B alleles in Holstein, respectively.