• Title/Summary/Keyword: BREEDING DENSITY

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Development of Narrow Leaf Type Cultivar "Konhee" in Zoysiagrass (세엽 한국잔디류 신품종 '건희(Konhee)' 육성)

  • 김두환;이재필;김종빈;모숙연
    • Asian Journal of Turfgrass Science
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    • v.13 no.3
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    • pp.147-151
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    • 1999
  • "Konhee" zoysiagrass[Zoysia matrella (L) Merr.](Patent registration no. 2000-723), a vegetative cultivar, was developed by the Dept. of Horticultural Science, Konkuk University, Seoul. "Konhee" was selected from the cross, ZKV6$\times$ZKV10, in 1997 and F1 seed were produced in the greenhouse in 1996. "Konhee" is superior to the other fine leaf zoysiagrass lines in many traits such as erect type, plant height($8.5\pm$2.0cm), short 3rd stolon length($3.4\pm$0.5cm), dark green, fine leaf($2.3\pm$0.2mm), low first sheath height($0.9\pm$0.2cm), rapid establishment and recoverage, many stolon number, and high shoot density. When "Konhee" was compared to the five other zoysisagrass lines at the DNA level using 35 PCR primers, it had the specific bands with primer No. 740, 544, 765, 772 by RAPD analysis.No. 740, 544, 765, 772 by RAPD analysis.

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Optimum Radial Build of a Low Aspect Ratio Tokamak Reactor

  • Hong, B.G.;Hwang, Y.S.;Kang, J.S.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.397-397
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    • 2011
  • In a low aspect ratio (LAR) tokamak reactor with a superconducting toroidal field (TF) coil, the radial build of TF coil and the shield play a key role in determining the size of a reactor. For self-consistent determination of the reactor components and physics parameters, a system analysis code is coupled with one-dimensional radiation transport code. Conceptual design study of a compact superconducting LAR tokamak reactor with aspect ratio less than 2.5 was conducted and the optimum radial build was identified. It is shown that the use of an improved shielding material and high temperature superconducting magnets with high critical current density opens up the possibility of a fusion power plant with compact size and small re-circulating power simultaneously at low aspect ratio, and that by using an inboard neutron reflector instead of breeding blanket, tritium self-sufficiency is possible with outboard blanket only and thus compact sized reactor is viable.

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Acoustic Communication of the Black-tailed Gull(Larus crassirostris) : the Structure and Behavioral Context of Vocalizations

  • Park, Shi-Ryong;Park, Dae-sik
    • Animal cells and systems
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    • v.1 no.4
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    • pp.565-569
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    • 1997
  • Vocal repertoires of the B1ack-tailed gull (Larus crassirostris) were studied at established reproductive colonies. The Black-tailed gull has eleven different vocal signals which can be grouped into three different call classes according to behavioral functions: contact call, alarm call (attention call), and aggressive call. The contact call or mew call is the most frequently used and functions as means of recognition among individuals, particularly between parents and youngs. Our results show that each call plays .an important role in particular social relationships in a high- density breeding colony.

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Mass Selection for Increased Lacquer Yield of Rhus verniciflua Stokes (산칠량(産漆量)이 많은 옻나무개체의 선발(選拔)에 관한 연구(硏究))

  • Hyun, Jung Oh;Kim, Mahn Jo;Lee, Shae Pyo
    • Journal of Korean Society of Forest Science
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    • v.82 no.2
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    • pp.122-127
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    • 1993
  • This study was conducted to investigate characteristics related to lacquer yield and to evaluate possibility of indirect selection of Rhus verniciflua Stokes. Twenty-four lacquer trees were randomly selected for measuring growth, urushiol content and bark thickness. Urushiol content showed a significant positive correlation with outer bark thickness and secretory canal density at 1% level, and with inner bark thickness at 5% level. Bark thickness and secretory canal density could be used as indicators for high urushiol content within bark and thus for high lacquer yield. Mass selection for high lacquer yield was made based on urushiol content within bark. Sixteen individuals with the highest urushiol content value were selected for breeding. As expected, the selected trees had thicker bark, higher density of secretory canal, better developed secretory canals compare to the non-selected lacquer trees.

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Does Visitation Dictate Animal Welfare in Captivity? : A Case Study of Tigers and Leopards from National Zoological Park, New Delhi

  • Gupta, Avni;Vashisth, Saurabh;Sharma, Mahima;Hore, Upamanyu;Lee, Hang;Pandey, Puneet
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.3 no.2
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    • pp.103-114
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    • 2022
  • Zoological Parks house exclusive animal species, thus creating a source of education and awareness for visitors. Big cats like tigers and leopards are among the most visited species in zoos globally. However, they often display stressful or stereotypic behaviours. Such behaviours are influenced by multiple factors including visitors, animal history, and captive environment. To understand this impact, we investigated the behavioural response of tigers and leopards to visitation, captive, and biological factors. The behaviour of eight big cats housed in the National Zoological Park, New Delhi, was monitored using focal sampling technique during May and June 2019. We recorded the captive and biological factors and visitor density for the subjects. The study revealed high proportions of inactive and stereotypic behaviours amongst the species. Tigers and leopards were found to perform stereotypic behaviours for 22% and 28% of their time, respectively. Generalised Linear Models revealed a significant variation of stereotypy in association with the factors. Stereotypy was influenced by visitor density, age, sex, breeding history, coat colour, and enclosure design. Adults, males, white-coated, previously bred, and those housed in smaller and simple enclosures display more stereotypy than young, females, normal-coated, unbred, and those housed in larger and complex enclosures, respectively. A high density of visitors induced more stereotypic behaviours amongst the big cats. As providing entertainment and awareness amongst the public is one of the fundamental objectives of the zoo, visitors can not be avoided. Thus, we suggest providing appropriate enrichments that would reduce stereotypies and promote naturalistic behaviours.

Genome-wide Single Nucleotide Polymorphism Analyses Reveal Genetic Diversity and Structure of Wild and Domestic Cattle in Bangladesh

  • Uzzaman, Md. Rasel;Edea, Zewdu;Bhuiyan, Md. Shamsul Alam;Walker, Jeremy;Bhuiyan, A.K.F.H.;Kim, Kwan-Suk
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.10
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    • pp.1381-1386
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    • 2014
  • In spite of variation in coat color, size, and production traits among indigenous Bangladeshi cattle populations, genetic differences among most of the populations have not been investigated or exploited. In this study, we used a high-density bovine single nucleotide polymorphism (SNP) 80K Bead Chip derived from Bos indicus breeds to assess genetic diversity and population structure of 2 Bangladeshi zebu cattle populations (red Chittagong, n = 28 and non-descript deshi, n = 28) and a semi-domesticated population (gayal, n = 17). Overall, 95% and 58% of the total SNPs (69,804) showed polymorphisms in the zebu and gayal populations, respectively. Similarly, the average minor allele frequency value was as high 0.29 in zebu and as low as 0.09 in gayal. The mean expected heterozygosity varied from $0.42{\pm}0.14$ in zebu to $0.148{\pm}0.14$ in gayal with significant heterozygosity deficiency of 0.06 ($F_{IS}$) in the latter. Coancestry estimations revealed that the two zebu populations are weakly differentiated, with over 99% of the total genetic variation retained within populations and less than 1% accounted for between populations. Conversely, strong genetic differentiation ($F_{ST}=0.33$) was observed between zebu and gayal populations. Results of population structure and principal component analyses suggest that gayal is distinct from Bos indicus and that the two zebu populations were weakly structured. This study provides basic information about the genetic diversity and structure of Bangladeshi cattle and the semi-domesticated gayal population that can be used for future appraisal of breed utilization and management strategies.

Signatures of positive selection underlying beef production traits in Korean cattle breeds

  • Edea, Zewdu;Jung, Kyoung Sub;Shin, Sung-Sub;Yoo, Song-Won;Choi, Jae Won;Kim, Kwan-Suk
    • Journal of Animal Science and Technology
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    • v.62 no.3
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    • pp.293-305
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    • 2020
  • The difference in the breeding programs and population history may have diversely shaped the genomes of Korean native cattle breeds. In the absence of phenotypic data, comparisons of breeds that have been subjected to different selective pressures can aid to identify genomic regions and genes controlling qualitative and complex traits. In this study to decipher genetic variation and identify evidence of divergent selection, 3 Korean cattle breeds were genotyped using the recently developed high-density GeneSeek Genomic Profiler F250 (GGP-F250) array. The three Korean cattle breeds clustered according to their coat color phenotypes and breeding programs. The Heugu breed reliably showed smaller effective population size at all generations considered. Across the autosomal chromosomes, 113 and 83 annotated genes were identified from Hanwoo-Chikso and Hanwoo-Heugu comparisons, respectively of which 16 genes were shared between the two pairwise comparisons. The most important signals of selection were detected on bovine chromosomes 14 (24.39-25.13 Mb) and 18 (13.34-15.07 Mb), containing genes related to body size, and coat color (XKR4, LYN, PLAG1, SDR16C5, TMEM68, CDH15, MC1R, and GALNS). Some of the candidate genes are also associated with meat quality traits (ACSF3, EIF2B1, BANP, APCDD1, and GALM) and harbor quantitative trait locus (QTL) for beef production traits. Further functional analysis revealed that the candidate genes (DBI, ACSF3, HINT2, GBA2, AGPAT5, SCAP, ELP6, APOB, and RBL1) were involved in gene ontology (GO) terms relevant to meat quality including fatty acid oxidation, biosynthesis, and lipid storage. Candidate genes previously known to affect beef production and quality traits could be used in the beef cattle selection strategies.

Study on the Protection and Management of Avifauna in Tokyusan National Park (덕유산 국립공원내 조류상의 보호 및 관리에 관한 연구)

  • 이우신;박찬열;조기현
    • Korean Journal of Environment and Ecology
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    • v.7 no.2
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    • pp.213-220
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    • 1994
  • This study was conducted to investigate bird community and to suggest a proper way how to manage and protect bird community in Tokyusan National Park. The survey was carried over 2 main trail districts by line transect method at 20, February and 22, July in 1993. The observed birds were belong to 5 orders 17 families 34 species, they also have Sparrow Hawk Accipiter nisus, Kestrel Falco tinunnculus(natural monument no. 323), White-backed Woodpecker Dendrocopos leucotos(R) and Japanese Waxwing Bombycilla japonica(R). It is estimated that grass region above 1,000m altitude provided breeding habitats for Gray-headed Bunting Emberiza fucata in summer and wintering habitats for Rosy Finch Leucosticte arctoa in winter, This shows that this region should be protected for inhabitation of these birds. Mujukucheontong valley of Tokyusan National Park, which had been a good habitat for valley-inhabituating birds before twenty years ago, has a lower species richness by increasing using density, and so this valley shoud be properly managed urgently.

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Population Change of Each Ardeidae Species in Damaged Habitats of Development Area (개발지역의 서식지 훼손에 따른 백로류 종별 개체군 변화)

  • Lee, Sang-Gi;Kim, Nam-Choon;Shin, Ji-Hoon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.17 no.1
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    • pp.147-162
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    • 2014
  • This study aims to provide the biological and geographical materials to identify the changes in population of Family Ardeidae included Egretta alba modesta, Egretta garzetta, Bubulcus ibis, and Nycticorax nycticorax and establish their conservation measurement in terms of the fragmented and deteriorated habitat by human development such as housing and park projects. Wonjucheon Stream was measured the highest species diversity since the survey site was relatively less interfered by the surrounding human beings showing lower disturbance elements. However, the closer the stream comes downstream, the more the artificial disturbance elements generate, confirming that the species better adapted to contamination grow in more density so that the species composition becomes simplified. It implies that feeding place as well as breeding-growing places is also more closely related to the changes in population structure and species composition of Family Ardeidae. The results of Family Ardeidae immigration in Taejang-dong, Wonju, among the other survey sites, revealed that a total of 231 came to the site in 2006; and 210 in 2011, showing more or less reduction in the population. In the mean while, Namyang-dong in Hwaseong City showed the continuous decrease in population number of Family Ardeidae with 135 before development and 60 during development, resulting in the number never growing but continuously narrowing over and over after development. As a result of surveying the number of Family Ardeidae that bred following the findings above, Taejang-dong in Wonju City had 4 species of Family Ardeidae being bred, however, showing the decrease in number of population from 998 in 2006 to 589 in 2011. Namyang-dong in Hwaseong was confirmed to have as many as 352 of the population in 2006 and 230 in 2008; after the deforestation on their habitat, they had not lived in the site any longer, suggesting that the development would significantly affect Family Ardeidae.

Gene Expression Analysis and Polymorphism Discovery to Investigate Drought Responsive System in Tropical Maize

  • Song, Kitae;Kim, Hyo Chul;Kim, Kyung-Hee;Moon, Jun-Cheol;Kim, Jae Yoon;Lee, Sang-Kyu;Lee, Byung-Moo
    • Plant Breeding and Biotechnology
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    • v.6 no.4
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    • pp.354-362
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    • 2018
  • Maize has high food and industrial value, whereas has difficulties in research because of their complex and huge size genome. Nested association mapping (NAM) was constructed to better understand maize genetics. However, most studies were conducted using the reference genome B73, and only a few studies were conducted on tropical maize. Ki3, one of the founder lines of the NAM population, is a tropical maize. We analyzed the genetic characteristics of Ki3 by using RNA sequencing and bioinformatics tools for various genetic studies. As results, a total of 30,526 genes were expressed, and expression profile were constructed. A total of 1,558 genes were differentially expressed in response to drought stress, and 513 contigs of them come from de novo assemblies. In addition, high-density polymorphisms including 464,930 single nucleotide polymorphisms (SNPs), 21,872 multiple nucleotide polymorphisms (MNPs) and 93,313 insertions and deletions (InDels) were found compared to reference genome. Among them, 15.0 % of polymorphisms (87,838) were passed non-synonymous test which could alter amino acid sequences. The variants have 66,550 SNPs, 5,853 MNPs, and 14,801 InDels, also proportion of homozygous type was higher than heterozygous. These variants were found in a total of 15,643 genes. Of these genes, 637 genes were found as differentially expressed genes (DEGs) under drought stress. Our results provide a genome-wide analysis of differentially expressed genes and information of variants on expressed genes of tropical maize under drought stress. Further characterization of these changes in genetic regulation and genetic traits will be of great value for improvement of maize genetics.