• Title/Summary/Keyword: populations

Search Result 5,217, Processing Time 0.032 seconds

Genetic Structure of Mongolian Goat Populations Using Microsatellite Loci Analysis

  • Takahashi, H.;Nyamsamba, D.;Mandakh, B.;Zagdsuren, Yo.;Amano, T.;Nomura, K.;Yokohama, M.;Ito, S.;Minezawa, M.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.21 no.7
    • /
    • pp.947-953
    • /
    • 2008
  • We studied genetic diversity and relationships among Mongolian goat populations on the basis of microsatellite DNA polymorphisms. DNA samples from eight populations (Bayandelger, Ulgii Red, Zavkhan Buural, Sumber, Zalaajinst White, Erchim Black, Dorgon, and Gobi Gurvan Saikhan) from geographically distinct areas of Mongolia were analyzed by using 10 microsatellite DNA markers. Since the 10 markers were highly polymorphic, the genetic characteristics of these native goat populations could be estimated. Genetic diversity within populations, as estimated by the expected heterozygosities, was high, ranging from 0.719 to 0.746, but genetic differentiation between populations was low, representing only 1.7% of the total genetic variation. The results suggest that Mongolian native goat populations still have a semi-wild genetic structure reflecting traditional Mongolian nomadism and the short history of artificial selection. The genetic relationships among the populations were not clear in the neighbor-joining tree generated from the modified Cavalli-Sforza chord genetic distances. By using principal components analysis, the five core populations of Mongolian native goats (Bayandelger, Ulgii Red, Zavkhan Buural, Sumber, and Dorgon) and the populations crossed with Russian breeds (Zalaajinst White, Erchim Black, and Gobi Gurvan Saikhan) were distinguished. There was no correlation between genetic relationships among the populations and the geographical distribution of the populations.

RAPD Analyses on the Regional Populations of Two Species of Saururaceae in Korea (삼백초와 식물 2종의 지역개체군별 RAPD 분석)

  • Tae, Kyoung-Hwan;Kim, Yong-Hyun;Tho, Jae-Hwa;Kim, Joo-Hwan
    • Korean Journal of Plant Resources
    • /
    • v.20 no.4
    • /
    • pp.272-280
    • /
    • 2007
  • In order to presume the genetic relationship about two species and their 30 regional populations of the Saururus and Houttuynia of Saururaceae, RAPD analyses were performed. The length of amplified DNA fragments ranged from 300 to 2,000 bp. 156 scorable RAPD makers were found from PCR reactions with sixteen random oligoprimers. Also, some regional populations were clustered separately from the UPGMA phenogram. The OTUs between cultivated and natural populations were distinguished distinctly on the UPGMA phenogram. And the regionals populations of the treated taxa were clustered. Among the regional populations of two species, GN populations had the close relationship JJ populations rather than JN populations. The RAPD data was very useful to define the genetic relationship and distinguish the cultivated populations from natural populations by regional distributions in this study.

Diversity in Six Goat Populations in the Middle and Lower Yangtze River Valley

  • Jiang, X.P.;Liu, G.Q.;Ding, J.T.;Yang, L.G.;Cao, S.X.;Cheng, S.O.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.16 no.2
    • /
    • pp.277-281
    • /
    • 2003
  • Amplified fragment length polymorphism (AFLPs) markers were used to investigate the genetic variation in six autochthonous goat populations distributed in the middle and lower Yangtze River valley. The goat populations were Chengdu Grey Goat (CGG), Chuandong White Goat (CWG), Banjiao Goat (BG), Matou Goat (MG), Hui Goat (HG) and Yangtze River Delta White Goat (YRDWG). A total of 180 individuals (30 per population) were analysed using ten selected AFLP primer combinations that produced 78 clear polymorphism loci. The variability at AFLP loci was largely maintained within populations, as indicated by the average genetic similarity, and they were ranged from 0.745 to 0.758 within populations and 0.951 to 0.970 between populations. No breed specific markers were identified. Cluster analysis based on Nei' genetic distance between populations indicated that Chengdu Grey Goat is the most distant population, while CWG and YROWG were the closest populations, followed by BG, HG and MG. Genetic diversity of the goat populations didn' confirm what was expected on the basis of their geographical location, which may reflect undocumented migrations and gene flows and identify an original genetic resource.

Geographical variations in the seed germination response and the seedling growth of hemistepta lyrata bunge by distrbution areas (分布地域에 따른 지침개 ( Hemistepta lyrata Bunge ) 個體群의 發芽 習性 및 幼植物 生長의 地理的 變異)

  • Lee, Ho-Joon;So-Hyun Park;Eun-Boo Cho
    • The Korean Journal of Ecology
    • /
    • v.16 no.1
    • /
    • pp.39-50
    • /
    • 1993
  • The geographical variation of the germination response and the seedling growth of the seed populations of hemistepta lyrata bunge distributed in the southern area of korean peninsula (seoul, yongwol, andong, $Ch^{\prime}angwon, \;Sunch^{\prime}on$)was investigated. Five populations were divided into two principal groups according to the phases of their seed germination. The first group consisting of the seoul and yongwol population was 62% and 64%, respectively, in the final germination percentage of 32%, 24% and 28%, respectively, were Andong, $Ch^{\prime}angwon\;and\;Sunch^{\prime}on$ populations. The seed populations of hemistepta lyrata bunge which hardly germination. the germination of seoul and yongwol populations located at the higher latitudes took plase synchronously in early autumn. On the other hand, andong, $Ch^{\prime}angwon\;and\;Sunch^{\prime}on$ populations located at the lower latitudes showed a tendency to germinata asynchronously in late autumn. the speed of the seedling growth of the populations located at the higher latitudes was greater than that of the populations at the lower latitudes. Therefore the geographical variation in the germination response and the seedling growth of the seed populations of hemistepta lyrate bunge appeared to be an important ecological strategy to maintain their existence in the extreme environmental variations.

  • PDF

Differences of Antioxidative Level in the Leaves and Seed Germinability among Five Natural Populations of Hibiscus hamabo

  • Han, Sim-Hee;Kim, Chan-Soo;Kim, Du-Hyun
    • Korean Journal of Plant Resources
    • /
    • v.21 no.3
    • /
    • pp.171-177
    • /
    • 2008
  • Variations in antioxidant capacity of leaves and characteristics of seed germination among five Hibiscus hamabo populations in Korea were evaluated. While the leaves of H. hamabo from Shincheon contained highest Na concentration, those from Hado and Ohzo does lowest. MDA content and SOD activity didn't show significant difference among populations, but total protein and anthocyanin content were significantly different among five populations. The filled seed rates of five populations were ranged from 92.0 to 98.7%, and the moisture contents of seeds from Shinyang and Soando were lower than that of R. syriacus (5.18%). The fresh weights of H. hamabo from Hado and Ohzo were the highest and those of seeds from Shinyang and Soando were the lowest. Significant variations among H. hamabo populations were detected for all seed germination characters: percentage of germination, average germination time and germination rate and uniformity. SOD activities of seeds from Onpyoung and Soando were the highest of five populations, and total protein concentrations of seeds in Ohzo and Shinyang populations were higher than those of other populations. H. hamabo is considered exposed to salt stress and all characteristics of seed germinations were inferior to other species.

Genetic Analysis of Haimen Chicken Populations Using Decamer Random Markers

  • Olowofeso, O.;Wang, J.Y.;Zhang, P.;Dai, G.J.;Sheng, H.W.;Wu, R.;Wu, X.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.19 no.11
    • /
    • pp.1519-1523
    • /
    • 2006
  • Through a screening and selection approach method, decamer random markers were used in a technique called random amplified polymorphic DNA (RAPD) assay with 252 genomic DNAs isolated from four major Haimen chicken populations: Rugao (62), Jiangchun (62), Wan-Nan (63) and Cshiqishi (65). A total of 3-score decamer random primers (S241-S260, S1081-S1100 and S1341-S1360) were employed in the preliminary RAPD-polymerase chain reaction (RAPD-PCR) assay with 50 random template DNA samples from all the populations. Four (6.67%) of the primers that produced obvious polymorphic patterns, interpretable and reproducible bands were selected and used with both the individual DNAs from each population and with pooled DNA samples of the four populations in subsequent analyses. The selected primers produced a total of 131 fragments with molecular size ranging from 835 to 4,972 base pairs (bp) when used with the individual DNAs; 105 (80.15%) of these fragments were polymorphic. With the pooled DNAs, 47 stable and characteristic bands with molecular size ranging from 840 to 4,983 bp, of which 23 (48.94%) polymorphic, were also generated. The band-sharing coefficient (BSC) calculated for the individuals in the population and among populations of bulked samples was between 0.8247 (Rugao) and 0.9500 (Cshiqishi); for pairwise populations, it was between 0.7273 (Rugao vs. Wan-Nan) and 0.9367 (Jiangchun vs. Cshiqishi) chicken populations. Using the BSC for individual and pairwise populations, the Nei's standard genetic distances between the chicken populations were determined and ranged from 0.0043 (Jiangchun vs. Cshiqishi) to 0.1375 (Rugao vs. Cshiqishi). The reconstructed dendrogram linked the Jiangchun and Cshiqishi chickens as closely related populations, followed by Wan-Nan, while the Rugao was the most genetically distant among the populations.

Genetic diversity and structure of natural populations of Picea jezoensis in South Korea

  • Lee, Seok Woo;Yang, Byeong Hoon;Hur, Seong Doo;Lee, Jung Joo;Song, Jeong Ho;Moriguchi, Yoshinari
    • Journal of Korean Society of Forest Science
    • /
    • v.97 no.2
    • /
    • pp.187-195
    • /
    • 2008
  • Picea jezoensis (Sieb. et Zucc.) Carriere is one of the major and widespread components of the cold-temperate and boreal forests in Russian Far East, northeast China, Korea, and Japan. However, it is restricted to a highly fragmented range in South Korea with small populations. Mean expected heterozygosity $(H_e)$ based on 22 loci in 11 isozyme systems was 0.077 for four sampled populations that covered the whole distribution range of P. jezoensis in South Korea. This value is within the range reported for conifers, but it is very low compared to that of other spruce species as well as that of P. jezoensis populations in Russian Far East. Most populations had a slight excess of heterozygotes and the Wright's $F_{IS}$ (-0.019) was comparable to that previously reported for other spruce species. In all of the four populations, the Wilcoxon sign-rank test indicated no greater heterozygosity than that expected for populations at mutation-drift equilibrium, suggesting that the populations have not been bottlenecked recently. Despite a fragmented range and isolated populations, population differentiation was not high $(F_{ST}=0.047)$ and the number of migrants per generation was 5.09. Nei's genetic distances were also small $({\bar{D}}=0.005)$ but strongly related to geographic distances between populations, suggesting an Isolation by Distance. The northernmost isolate, Mt. Gyebang population was genetically distinct from the other three populations. Implications for the conservation of genetic variation of P. jezoensis in South Korea were discussed.

Genetic diversity and herbicide resistance of 15 Echinochloa crus-galli populations to quinclorac in Mekong Delta of Vietnam and Arkansas of United States

  • Le, Duy;Nguyen, Chon M.;Mann, Richard K.;Yerkes, Carla N.;Kumar, Bobba V.N.
    • Journal of Plant Biotechnology
    • /
    • v.44 no.4
    • /
    • pp.472-477
    • /
    • 2017
  • Barnyardgrass (Echinochloa crus-galli) is one of the worst weeds in rice (Oryza sativa), but there are few reports about the genetic diversity and herbicide resistance of barnyardgrass in Vietnam. In this study, we used random amplified polymorphic DNA (RAPD) analysis and greenhouse testing to study the genetic diversity and quinclorac resistance levels of 15 Echinochloa crus-galli populations in the Mekong Delta, Vietnam, and the state of Arkansas, U.S. The quinclorac resistance of Echinochloa crus-galli populations in Vietnam was confirmed; 9 populations were resistant to quinclorac with R/S ratios ranging from 1.9 to 6.3. Six oligonucleotide primers produced a total of 55 repeatable bands of which 46 were polymorphic (83.3% average) among the 15 populations. Genetic distance was calculated, and cluster analysis separated the 15 populations into 2 main clusters with the genetic distances within the clusters ranging from 0.09 to 0.39. The two main clusters were divided into 7 subclusters, and the quinclorac resistant and susceptible populations were located randomly within each subcluster. Six out of 13 weed populations from Vietnam belonged to one cluster and a single Echinochloa species. The remaining 7 populations were identified as potentially different species in the Echinochloa genus. Nine Echinochloa populations from Vietnam were tested and identified as quinclorac resistant. The connection between quinclorac resistance levels and weed groups defined by RAPD analysis in the study is unclear; the quinclorac resistance of each resistant population could have evolved individually, regardless of differences in genetic diversity and location of the sampled populations.

Genetic Relationship Between Korean and Mongolian Populations Based on the Y Chromosome DNA Variation

  • Jin, Han-Jun;Kim, Wook
    • Animal cells and systems
    • /
    • v.7 no.2
    • /
    • pp.139-144
    • /
    • 2003
  • We analyzed seven Y chromosome binary markers (YAP, RPS4Y_711,\;M9,\;M175,\;LINE1,\;SRY_+465$ and 47z) in samples from a total of 254 males from Koreans and tow Mongolian ethnic groups (Buryat and Khalkh) to study the genetic relationship among these populations. We found eight distinct Y haplogroups constructed from the seven binary markers. Haplogroup DE-YAP was present at extremely low frequencies (∼2%) in the Korean and Mongolian populations. This result is consistent with earlier reports that showed the YAP+ chromosomes to be highly polymorphic only in populations from Japan and Tibet in east Asia. The observed high frequency of haplogroup $C-RPS4Y_711$ in the Mongolian populations (∼40%) is concordant with recent findings, showing that the $RPS4Y_711$-T chromosomes were distributed at high frequencies in Siberian and Mongolian populations compared with most other populations from east Asia. Thus, the relatively moderate frequency of haplogroup $C-RPS4Y_711$ in Korean (∼15%) can be seen as genetic evidence for probable interaction with Mongolian and/or Siberian populations. In contrast, the majority (∼75%) of modern Koreans studied here had high frequencies of Y chromosome lineages of haplogroup O-M175 and additional haplogroupts that define sublineage of O-M175, which are most likely related with modern populations in China. In conclusion, our data on the Y chromosome haplogroup distribution may provide evidence for interaction between Korean and Mongolian populations, but Korean tend to be much more related with those from southern-to-northern populations of China than to Mongolians in east Asia.

A study on the structure evolution of neural networks using genetic algorithms (유전자 알고리즘을 이용한 신경회로망의 구조 진화에 관한 연구)

  • 김대준;이상환;심귀보
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1997.10a
    • /
    • pp.223-226
    • /
    • 1997
  • Usually, the Evolutionary Algorithms(EAs) are considered more efficient for optimal, system design because EAs can provide higher opportunity for obtaining the global optimal solution. This paper presents a mechanism of co-evolution consists of the two genetic algorithms(GAs). This mechanism includes host populations and parasite populations. These two populations are closely related to each other, and the parasite populations plays an important role of searching for useful schema in host populations. Host population represented by feedforward neural network and the result of co-evolution we will find the optimal structure of the neural network. We used the genetic algorithm that search the structure of the feedforward neural network, and evolution strategies which train the weight of neuron, and optimize the net structure. The validity and effectiveness of the proposed method is exemplified on the stabilization and position control of the inverted-pendulum system.

  • PDF