• Korean Journal of Poultry Science
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• v.8 no.1
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• pp.1-5
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• 1981

In trying to predict the effect of genetics on the broiler in the year 2000, this is a relatively short period of time as far as broiler genetics in concerned. Modern broiler genetics started around 1945 and tremendous gains when made in past 35 years. Futher improvements on broiler will depend on the evolution and revolution: 1. Evolution: (1) Growth rate has been made 4-5% per year. (2) Feed conversion has improved approximately 1% per year. (3) Abdominal fat is becoming a major complaint in broiler. (4) Because of the changing life-style, broiler meat sales in the future will be more and more in cut-up form. (5) Breeding for stress resistance and selection for docile temperament can be important in order to funker improve fled efficiency. (6) In female parent stock, reproduction characteristics are in many can negatively correlated with the desired broiler traits. (7) Egg production and hatchability in moot commercial parent nod m at a fairly high level. (8) In male parent stock, the heavier and mon super-meat-type male lines are desired to Product better broilers. 2. Revolution: Trying to forecast revolutionary change in broiler genetics is highly speculative, as sudden change are aften unpredictable. (1) Species hybridization, such as a turkey-chicken cross (2) Biochemical tools, such as blood typing. (3) Mutation breeding by radiation or chemical mutagentia. (4) Broiler breeding would be to change the phenotypic appearance by single gene, such as naked, wingless. (5) Changes in production techniques. such as growing in cage or growing in filtered air positive pressure houses.

• Journal of agriculture & life science
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• v.45 no.2
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• pp.61-67
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• 2011

To provide basic data for variety improvement of chestnut cultivated in southern Korea, nut characteristics were investigated during 2008-2010. The number of burr by variety ranged from 37.7 in Kwangjujoyul to 183 in Juok. There were significant differences among variety in number of nuts per burr, and Idea had the least number of nuts per burr (1.2), while Sandae and Kwangeun had the largest (2.0). Nut weight also showed a distinct difference among variety, and Kwangdeok had the heaviest, while Kwangjujoyul had the lightest nut weight. Changbanggamyul showed the highest healthy nut rate of 89.9%, and Kunumi, Arima, Tsukuba, Kwangeun, and Pyeonggi had the rate of healthy nut of more than 80%. Sinyipyeong and Isseumo showed the high rate of rot nuts of 10.8 and 16.8%, which was needed to give attention to nut storage. Split pericarp percentage ranged from 0% in Changbanggamyul to 20.6% in Saeil, and that was above 15% in Sandae, Riheiguri, Juok, Kwangdeok but Kunumi, Arima, Tsukuba, Manseong, Changbanggamyul, Chuckpabyunii, Isseumo had the split pericarp percentage of less than 3%.

• Journal of Sericultural and Entomological Science
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• v.36 no.1
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• pp.1-7
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• 1994

Four tetraploid mulberry lines, Sawonppon No.11, No.13 and No.14, were induced by the colchicine treatment on the shoot tips of seedlings originated from the cross between Yongchonppong and Kaeryanppong. The major characteristics of the tetraploid lines were as follows: Green tip sprouting stage was similar to Kaeryanppong, a medium budding variety. Leaves were medium- to large-sized cordate type. Leaf surface was rougher and stronger than that of the diploid parents. Leaf thickness, leaf area weight and leaf water content were higher than those of the diploid parents. Average branch length was shorter than that of the diploid parents. Internode length and number of lateral branches were similar to the average values of the two parents. Death atop rate of branch was 1.6%~2.5% indicating strong cold-hardiness of the tetraploid lines. Therefore, these lines could be used as sources of cold-hardiness in developing triploid lines.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.427-433
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• 2014

Trellising is an important cultural practice that affects grape quality and yield. Some grape cultivars require different trellising under different climate and soil conditions. To find suitable trellis conditions for grape cultivar 'Cheongsoo', we measured growth and fruit characteristics with three different trellis systems: curtain, Geneva double curtain (GDC), and modified T. The maximum light exposure of clusters in the curtain, GDC, modified T trellis systems was 670, 1,654, and $1,649{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, respectively. However, there was no difference in air temperature among the three trellis systems. Net $CO_2$ assimilation rate at $1,500{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ light intensity was 13.4, 13.7, and $8.7{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ in curtain, GDC, and modified T trellis systems, respectively. Trunk cross section area (TCSA) and bud burst rate were not significantly different among the three systems. Shoot number was 31.3, 47.0, and 37.0 in curtain, GDC, and modified T trellis systems, respectively. The shoot length was higher (243.9 cm) in the modified T trellis system than in the single curtain (171.1 cm) and GDC (151.5 cm) systems. Interior leaf number and leaf layer number were higher in the GDC system, in which there are two primary branches, in comparison to the modified T and curtain systems, which utilize one primary branch. Primary leaf area and lateral leaf area were significantly higher in the modified T trellis system in comparison to the GDC system. Berry weight, length and diameter, and total soluble solids were not significantly different among the three trellis systems. However, cluster weight and cluster number per tree were significantly higher in GDC. Titratable acidity was significantly lower in GDC. Collectively, our data suggest that the GDC trellis system is preferable for grape 'Cheongsoo' to maintain fruit quality and quantity in Korea.

• KOREAN POULTRY JOURNAL
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• v.15 s.162
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• pp.106-109
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• 1983

브로일러 종계의 평균능력은 혈통의 유전적 잠재력과 그 품종이나 계통의 관리 여하에 따라 여러 형태로 표현된다. 실제로 종계에서 나타나는 변이는 일반적으로 유전적인 차이보다 관리에 의해 더 많이 좌우된다. 여기서는 종계의 생산성 향상과 능력 개량을 좀 더 구체화시키기 위해 1976년부터 1981년까지 6년간의 자료를 구했다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.5
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• pp.440-448
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• 1990

To obtain the basic information an seed quality improvement in sesame, protein content of 114 varieties and amino acid composition of 12 varieties was analyzed. Protein content showed the vaietal difference ranged 20.6-30.2% and the mean was 24.72%. The highest variety in protein content was PI158066 (30.2%) originated from U.S.A. Protein content of Korean local varieties were highest among original group analyzed. Seed coat texture and seed coat color affected to protein content so, smooth type was higher than rough type in protein content, and black seeded varieties showed the hight protein content. Amino-acid composition of sesame was uneque in balance and higher than FAO reference. Total amino-acid of variety PI258372 was highest as 25.03%. Essential amino-acid (EAA) /total amino-acid(TAA) ratio of sesame was higher as 42-58.2% than soybean, corn, rice, peanut. Korean local variet 'Samcheck' showed best quality in amino-acid composition as 58.2% in EAA/TAA ratio with high tyrocin and lysine. Total amino acid content was high in order of Korean local '||'&'||'gt; introduced '||'&'||'gt; Korean bred varieties.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.269-277
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• 2008

Amino acid composition in grain of Korean native rice core collections was evaluated to identify the useful genotypes for quality enhancing rice breeding and value-added food development. Large variations were found in the contents of 16 amino acids among 388 genotypes tested with 14.9% of the minimum coefficient of variation (CV), and the contents of methionine and histidine showed the highest CV and the second high, respectively. The average values of total amino acid, total essential amino acid, lysine and threonine contents of Korean native rice collections were almost similar with those of cultivating japonica rice, Saechucheong. Among 388 native core collections Baekkokna, Daesona and Saducho were identified as high amino acid germplasm in total amino acid, total essential amino acid, lysine and threonine contents. And Seoksanjo and Sodujo were identified as low amino acid collections. Rice collections showing purple apiculus color tended to distribute in lower serine, proline, glutamic acid, glycine, alanine, valine, leucine, phenylalanine, arginine, and total amino acid contents compared with those of yellowish apiculus color collections. The glutinous rice collections showed the tendency of higher contents of serine, glutamic acid, alanine, valine and leucine compared with those of non-glutinous collections.

• The Korean Journal of Food And Nutrition
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• v.26 no.4
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• pp.685-692
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• 2013

Yuza (Citrus junos) has 3 varieties with variable physiochemical properties. This study analyzed these volatile compounds and physiochemical properties according to variety. Three Yuza varieties, native (Citrus junos I), improved I (Citrus junos I+Poncirus trifoliata), improved II (Citrus junos I+C. junos II) were used. The native Yuza weighted more than the improved varieties, but the peel ratio (weight of peel versus pulp) was high in improved one. Protein and ash contents were high in Improved I than native one. Native had 29.6mg% vit. C in pulp and improved I had 57.7mg% vit. C in peel. Free sugar was mainly fructose, and the main organic acid was citric acid in Yuza. Improved I Yuza had high free sugar contents, and the organic acid levels were high in improved II Yuza. Linoleic acid was the most prevalent fatty acid in Yuza; it was distributed in peel or pulp. The most common volatile flavor component was dl-limonene (64~70%); improved II Yuza showed significantly higher contents of dl-limonen and ${\gamma}$-terpinen. Total phenol level of Yuza was identical in all types, but peels had 2.5 times more than pulps.

• Monthly Duck's Village
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• v.62 no.8
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• pp.50-53
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• 2008

페킨종은 중국이 원산으로 미국과 영국에서 개량되어 현재 세계 각국에서 널리 사육되고 있는 난육겸용종의 대표적인 품종이다. 페킨종을 종자로 이용하여 육종한 육용개량 좋은 체구가 크고 발육도 빨라 현재 전세계에서 오리고기 생산용으로 많이 사육되고 있다. 페킨종 오리의 생산은 상업용 가금산업 중에서도 고도로 전문화된 분야이다. 종오리의 번식력은 육계나 산란계들 사이에서도 굉장히 높게 나타난다. 그러나 페킨종 오리의 경우 사육시 상당히 특별하고 흥미롭기 때문에 관리상의 필요한 점이 굉장히 많다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.4
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• pp.343-349
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• 1993

This study was conducted 1)to determine the factors responsible for the gradually increased rice yield by examining any improvements in yield-related characters and physiological characters among the historically recommended varieties of rice in Korea, and 2)to reveal the way of achieving further yield improvement by breeding in the future. Eight recommended varieties from 1911 to 1988 were selected and grown at the same conditions. The yield-related characters were observed at the harvest time, and the physiological characters such as RGR, NAR, LAR, SLA and L WR were estimated by the classical method of growth analysis. The newer varieties are shorter and those released after 1970's are greater in percent of filled spikelets and harvest index than the older varieties. There are no definite changing trends in the variations of number of panicles per hill, number of spikelets per panicle and 1000 grain weight according to the course of evolution in the recommended varieties. There is little evidence of improvement in the physiological characters such as NAR, LAR, SLA and LWR among the recently developed varieties compared with those of the older varieties. The increase in grain yield due to variety improvement, if any, is largely associated with the greater harvest index and percent of filled spikelets by breeding blight resistant and / or lodging resistant genotypes with short culm. It is suggested that increase in NAR should be carried out simultaneously with increase in harvest index to breed high yielding genotypes. I t appears to be important to breed genotypes with long culm in order to enhance light penetration into the canopy as long as they are lodging resistant. Since NAR is negatively correlated with LAR, it is unlikely to succeed to improve both characters simultaneously. The direct effect of NAR on RGR by path analysis is much larger than that of LAR, and hence it is suggested that breeding genotype with large NAR is more effective on enhancing RGR. It is also suggested that improving LAR through LWR is likely effective on increasing RGR.