• 한국작물학회지
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• 제1권1호
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• pp.42-45
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• 1963

In a plant breeding program, an efficient selection of desired characters in a population is important. Generally, many agronomic characters in a given population are determined by polygenes and quantitatively inherited. In practice, the genetic relationship between two observed characters which are undoubtedly subjected to the environmental influence is difficult to identify. In recent years, many workers have attempted to understant the genetic relationship between characters in terms of genotypic correlation, and the knowledge thus gained should furnish many important and useful information for the planning of breeding, selection, and interpretation of the result. The genotypic correlation is the result of pleiotropy, linkage of genes(2, 3, 5, 6, 8) and natural or artificial selection(4). The purposes of this study were to estimate genotyric and phenotypic correlations between all possible pairs of nine characters. and to seek certain characters which may be useful as indicators of certain important agronomic characters. Weber and Moorthy(10), Johnson et al. (5) and Sheth(7) found that in general, the genotypic correlations were higher than the phenotypic correlations. Weiss et al. (11) obtained significant positive correlations between maturity and oil content, maturity and low protein content, and high protein content and low oil content. Weber and Moorthy(10) reported the positive genotypic correlations between flowering and maturity, yield and maturity, yield and plant height, yield and seed weight, and negative genotypic correlations between maturity and oil content, and oil content and seed weight. Johnson et al. (5) studied the genotypic and phenotypic correlations among 24 characters and concluded that selection based entirely on a long fruiting period, lateness, heavy seed, low protein, high oil and resistance to lodging would be effective in increasing yield. Sheth(7) found the following positive associations among characters; height and maturity, yield and lodging, low protein content and high oil content, and yield and low protein content. Hanson et al.(1) also reported high negative correlation between seed yield and protein content.

• Journal of Animal Science and Technology
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• 제63권5호
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• pp.1064-1075
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• 2021

Recently, a high level of dietary crude protein (CP) has become of interest as a possible practice to improve the carcass quality of beef cattle, and its level has been increasing in the field. However, there is little scientific evidence that supports this. This study was conducted to test whether a high dietary CP level would improve growth performance, body metabolism, and carcass traits in Hanwoo beef cattle. A total of 32 Hanwoo finishing beef cattle (18 multiparous cows, six heifers, and eight steers) participated in a 12-weeks feeding trial. Two kinds of total mixed rations were prepared to contain two different CP; 156 g/kg for the control (CON) and 173 g/kg of CP for the treatment (HCP), while maintaining a similar level of metabolizable energy. The experiment was ended when more than half of the steers reached the target body weight (730 kg). Blood was collected at the end of the experiment. After harvesting, the carcass trait was evaluated at the slaughterhouse according to Korean standards. The carcass yield score and grade were also calculated based on revised criteria. Overall, dry matter intake, average daily gain, blood metabolites concentration, and the carcass traits, except for backfat thickness and the yield score, did not differ between the treatments. The HCP had lower backfat thickness than those of CON. There was no difference in the carcass yield grade, but the yield score was higher in the HCP treatment. According to the newly revised carcass grading criteria, both yield score and grade were higher in HCP than in CON. Increasing CP supply decreased the carcass's backfat thickness without altering growth performance and body metabolism, resulting in improved yield score and grade. Therefore, feeding a high CP diet may be beneficial in the farm income, although it may also increase feed cost and nitrogen excretion to the environment.

• 한국초지조사료학회지
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• 제27권4호
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• pp.263-268
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• 2007

축산분뇨를 이용한 사료작물을 재배할 때에 가장 큰 문제점은 지나치게 생육이 왕성하여 수확 전에 도복되는 문제점으로 대두되어 본 연구는 논토양의 유기물함량에 따른 품종별 작물학적 특성, 수량 및 사료가치에 미치는 영향을 알기 위하여 선우보리, 영양보리, 상원보리, 우호보리, 소만보리, 유연보리 등 6품종을 비옥도가 다른 논토양에 2006년 10월 18일에 파종하여 연구한 결과 공시품종 중에서 비옥지에서는 우호보리와 소만보리가 내도복성이 강한 것을 알 수 있었으나 보통지에서는 선우보리, 상원보리, 우호보리 등이 도복에 강한 특성을 보임을 알 수 있었다. 생체수량이나 건물수량 측면에서 살펴보면 비옥지 토양이나 보통지에서는 품종간 뚜렷한 차이를 보이지 않았지만 척박지에서는 건물수량이 영양보리(8,350 kg/ha)와 소만보리(8,450 kg/ha)가 가장 높은 수량을 보여 유기물 함량이 적은 논토양에 보리를 재배할 때에는 영양보리나 소만보리가 유망하였다. 사료가치 측면에서 살펴보면 조단백질은 척박지<보통지<비옥지 순으로 토양이 비옥할수록 조단백질 함량이 많았지만 소화율은 비옥지보다는 보통지나 척박지에서 높았고, 품종별로 보면 비옥지에서 영양보리, 유연보리가 각각 78.7%, 74.7% 등으로 높았다. 총체보리품종들의 TDN 함량은 비옥지<보통지<척박지 순으로 각각 67.2%, 69.0%, 71.1% 등으로 척박지에서 높았고 비옥지에서는 유연보리가 70.3%로 가장 높았으며 다음으로 영양보리가 69.5%를 보였고 척박지에서는 소만보리가 76.7%이고 우호보리는 72.2%로 높았다. 이와 같은 결과를 종합하면 논토양에 총체용 보리 우량 품종은 척박지 토양에서는 영양보리와 소만보리, 보통지 토양은 선우보리와 상원보리, 비옥지 토양은 도복에 강하고 사료가치가 높으며 수량이 다소 많은 우호보리와 소만보리 등이 적합하였다.적

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2005년도 학술발표회 논문집
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• pp.211-219
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• 2005

Nowadays, various grades of high-strength steels are available. The application of ultra-high grades of steels for building structures, however, is limited only to the elements stressed under tension. The highest grade of steels generally used has a tensile strength of around 600N/mm2. Most research is focused on lower yield ratios of high strength steel in the inelastic range to ensure the stability of structures. In this paper, however, the possibility of an effective application of high strength steel with high yield ratio to building structures is discussed. An efficient structural system and a design method based on earthquake response analysis and experimental results are proposed.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.223-223
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• 2017

This study aimed to determine the effect of organic matter content and water condition in soil on yield, carbohydrate, and inulin contents of two varieties of Jerusalem artichoke. The plants were grown with high and low organic soil either under irrigation or no irrigation in a randomized complete block design (RCBD) with three replications. In result, the yield of Jerusalem artichoke was higher about 7 kg in soil with high organic matter than in soil with low organic matter, while it was higher about 11 kg under the irrigation than under no irrigation. The yield of white variety was higher about 9 kg than that of purple variety. Under the irrigation, a 12 kg and 9 kg of higher yields were observed in the soil with high and low organic matter content, respectively, than under no irrigation.

• 한국초지조사료학회지
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• 제14권1호
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• pp.42-49
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• 1994

To examine the productivity, growth characteristics, and nutritive value of forage rye at the southern region of Korea, fourteen varieties of rye were sown at Nov. 13, 1992 at the plot of experiment farm of Crop Experiment Station, Mokpo Branch, and over winter survival rate, heading date, yield, yield components and nutritional values were measured. All the varieties used in this experiment showed 100% over winter survival rate at the sowing date of Nov. 13. Heading dates of all the varieties ranges from Apr. 25 to May 10, which seems to be early enough to get high yield. The varieties, Paldal-hod, and Danko introduced from Japan appear to be the most recommended ones in the southem region of Korea. They showed early heading date of Apr. 25, large plant height, greater number of leaves, high yield, low content of crude fiber and crude fat, high crude protein, NFE, and crude a5h.

• 한국자원식물학회지
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• 제20권4호
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• pp.321-324
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• 2007

벼 재배기술의 개선방향을 모색코자 객토 철분 및 규산질 비료를 첨가하여 다수확 재배 실험하였던바 보통재배구에 비하여 간장, 수장은 길고 수수도 많았으며 현미천입증도 무거워서 현미수량은 544.7kg/10a로 보통재배구의 431.8kg/10a보다 26% 증수였다.

• Animal Bioscience
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• 제34권9호
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• pp.1466-1478
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• 2021

Objective: Ruminants are completely dependent on their microbiota for rumen fermentation, feed digestion, and consequently, their metabolism for productivity. This study aimed to evaluate the rumen bacteria of lactating yaks with different milk protein yields, using high-throughput sequencing technology, in order to understand the influence of these bacteria on milk production. Methods: Yaks with similar high milk protein yield (high milk yield and high milk protein content, HH; n = 12) and low milk protein yield (low milk yield and low milk protein content, LL; n = 12) were randomly selected from 57 mid-lactation yaks. Ruminal contents were collected using an oral stomach tube from the 24 yaks selected. High-throughput sequencing of bacterial 16S rRNA gene was used. Results: Ruminal ammonia N, total volatile fatty acids, acetate, propionate, and isobutyrate concentrations were found to be higher in HH than LL yaks. Community richness (Chao 1 index) and diversity indices (Shannon index) of rumen microbiota were higher in LL than HH yaks. Relative abundances of the Bacteroidetes and Tenericutes phyla in the rumen fluid were significantly increased in HH than LL yaks, but significantly decreased for Firmicutes. Relative abundances of the Succiniclasticum, Butyrivibrio 2, Prevotella 1, and Prevotellaceae UCG-001 genera in the rumen fluid of HH yaks was significantly increased, but significantly decreased for Christensenellaceae R-7 group and Coprococcus 1. Principal coordinates analysis on unweighted UniFrac distances revealed that the bacterial community structure of rumen differed between yaks with high and low milk protein yields. Furthermore, rumen microbiota were functionally enriched in relation to transporters, ABC transporters, ribosome, and urine metabolism, and also significantly altered in HH and LL yaks. Conclusion: We observed significant differences in the composition, diversity, fermentation product concentrations, and function of ruminal microorganisms between yaks with high and low milk protein yields, suggesting the potential influence of rumen microbiota on milk protein yield in yaks. A deeper understanding of this process may allow future modulation of the rumen microbiome for improved agricultural yield through bacterial community design.

• International Journal of Industrial Entomology and Biomaterials
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• 제4권2호
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• pp.143-147
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• 2002

Studies on the interrelationship between biological yield and harvest index, and their association with shoot rearing were carried out in 9 promising mulberry genotypes, which indicated significant variations among genotypes. Biological yield had close association with leaf yield components indicating that they are inter-related for higher productivity in mulberry, Biological yield revealed highly significant positive correlation with important leaf yield components. However height of the longest branch showed negative correlation with biological yield. Genotypes with higher biological yield associated with low ratio of stem weight to leaf weight and high Harvest index on dry weight basis are to be selected for shoot rearing. Biological yield recorded on fresh weight basis had less impact on the present study in comparison to dry weight basis.

• 한국초지조사료학회지
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• 제9권2호
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• pp.108-112
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• 1989

To determine optimal plant density of forage rape in southern areas of Korea, Velox, the highest yielding variety among seventeen introduced varieties of forage rape, was grown under five different plant densities. The results obtained are summarized as follows: 1. Yield components such as stem diameter, number of main stem,leaves, number of branches and number of branch leaves and fresh yield were highest at the plots with 50cm row spacing and 30cm plant spacing. 2. Dry matter yield, content of crude protein, IVDMD and digestible dry matter yield were highest at the plots of broadcasting. 3. Since plants under high density were high in plant length and small in stem diameter, contents of crude fiber such as NDF, ADF, cellulose and lignin were lowest at the plots of broadcasting.