scholarly journals Variability of ventral scales in polish populations of Conocephalum conicum (L.) Dum. (Hepaticae, Marchantiales)

2015 ◽  
Vol 47 (4) ◽  
pp. 417-427
Author(s):  
Jerzy Szweykowski ◽  
Maria Anna Bobowicz
Keyword(s):  
Geographic Distribution ◽  
Natural Populations ◽  
Genetic Differences ◽  
Conocephalum Conicum ◽  
Habitat Ecology

Samples taken from 6 natural populations of the liverwort species <i>Conocephalum conicum</i> were cultivated in a glasshouse and the variability of 9 ventral scale characters was studied in them. Genetic differences were discovered between population samples but all the attempts to correlate them with the geographic distribution and/or habitat ecology have failed so far.

STUDIES OF NATURAL POPULATIONS OF MUS. V. A SURVEY OF NINE LOCI FOR POLYMORPHISMS

1969 ◽  
Vol 11 (3) ◽  
pp. 497-513 ◽  
Author(s):  
M. L. Petras ◽  
J. D. Reimer ◽  
F. G. Biddle ◽  
J. E. Martin ◽  
R. S. Linton
Keyword(s):  
Geographic Distribution ◽  
Mus Musculus ◽  
Additional Data ◽  
Natural Populations ◽  
House Mice ◽  
Polymorphic Loci

An examination of house mice (Mus musculus) from a number of sites in southwestern Ontario revealed six loci (Hbb, Es-2, Es-3, Es-5, Ldr-1 and A) to be polymorphic and three (Es-1, Pro-1 and Trf-1) to be monomorphic. A comparison of the Ontario samples with samples from southeastern Michigan suggests that the polymorphisms detected are common to Mus populations in both regions and are relatively stable. Data reported by other investigators suggest that some of these polymorphisms have a broad geographic distribution. Also discussed are findings of loci described elsewhere. Two of these T and Ea-1, are polymorphic in some of the populations under consideration. General conclusions include: (1) that polymorphic loci are probably as frequent in mouse populations as in Drosophila and man; (2) that the polymorphisms observed are relatively stable and widespread; (3) that some of the alleles responsible for the polymorphisms observed are not neutral; and (4) that additional data are necessary to elucidate the mechanisms responsible for the polymorphisms observed.

scholarly journals Extending the Genotype in Brachypodium by Including DNA Methylation Reveals a Joint Contribution with Genetics on Adaptive Traits

2020 ◽  
Vol 10 (5) ◽  
pp. 1629-1637 ◽  
Author(s):  
Steven R. Eichten ◽  
Akanksha Srivastava ◽  
Adam J. Reddiex ◽  
Diep R. Ganguly ◽  
Alison Heussler ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Dna Methylation ◽  
Phenotypic Variation ◽  
Genetic Relationships ◽  
Natural Populations ◽  
Epigenetic Inheritance ◽  
Genetic Differences ◽  
Linear Modeling ◽  
Climate Conditions ◽  
Joint Contribution

Epigenomic changes have been considered a potential missing link underlying phenotypic variation in quantitative traits but is potentially confounded with the underlying DNA sequence variation. Although the concept of epigenetic inheritance has been discussed in depth, there have been few studies attempting to directly dissect the amount of epigenomic variation within inbred natural populations while also accounting for genetic diversity. By using known genetic relationships between Brachypodium lines, multiple sets of nearly identical accession families were selected for phenotypic studies and DNA methylome profiling to investigate the dual role of (epi)genetics under simulated natural seasonal climate conditions. Despite reduced genetic diversity, appreciable phenotypic variation was still observable in the measured traits (height, leaf width and length, tiller count, flowering time, ear count) between as well as within the inbred accessions. However, with reduced genetic diversity there was diminished variation in DNA methylation within families. Mixed-effects linear modeling revealed large genetic differences between families and a minor contribution of DNA methylation variation on phenotypic variation in select traits. Taken together, this analysis suggests a limited but significant contribution of DNA methylation toward heritable phenotypic variation relative to genetic differences.

Morpho-phenological diversity among Tunisian natural populations of Brachypodium hybridum

2014 ◽  
Vol 153 (6) ◽  
pp. 1006-1016 ◽  
Author(s):  
M. NEJI ◽  
F. GEUNA ◽  
W. TAAMALLI ◽  
Y. IBRAHIM ◽  
M. SMIDA ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Geographic Distribution ◽  
Phenotypic Diversity ◽  
Average Length ◽  
Natural Populations ◽  
Negative Relationship ◽  
Mantel Test ◽  
Population Variation ◽  
Long Distance ◽  
Temperate Cereal

SUMMARYBrachypodium hybridum belongs to the Poaceae grass subfamily. It has a close genetic relationship with temperate cereal crops, which means that it can be used as a model for temperate cereal and grass crops. In order to improve knowledge on the genetic diversity of this species, 145 lines of B. hybridum representative of nine populations and all the ecoregions of Tunisia were characterized on the basis of 18 morpho-phenologic features. The results show a considerable variation between populations and ecoregions in all traits studied. Variation was relatively higher for reproductive than vegetative traits. The majority of traits showed very low to high heritability with low border value for average length of spikelet (ALS) and an average value of 0·64. It is noticeable that high values of heritability were observed for most vegetative descriptors, with low values for reproductive ones. Differentiation between populations (QST) varied from 0·02 for ALS to 0·78 for average length of leaves with a mean value across traits of 0·4, which confirms the wide intra-population variation in Tunisian natural population of B. hybridum. Pairwise QST showed that the greatest differentiation among populations was registered between Ain Drahem and Jbel Zaghouan and the smallest between Haouria and Raoued. Overall, the Ain Draham population showed the largest differentiation from the rest of the populations. To infer the effect of geographic distribution of the species, a Mantel test was applied between observed pairwise differentiation and geographic distance between populations and between ecoregions: the results show a positive, but not significant, relationship. In addition a significant negative relationship was found between phenotypic diversity and altitude, indicating that genetic diversity decreased with increasing altitude. Taken together, the high levels of intra-population variation and the lack of correlation between genetic differentiation and geographic distribution suggest a potentially important rate of long-distance seed dispersal and confirm the role played by natural selection in the population structure of Tunisian natural populations of B. hybridum.

Morphological and isozyme variation in Cerastium arvense (Caryophyllaceae) in the southern Andes

2002 ◽  
Vol 80 (7) ◽  
pp. 786-795 ◽  
Author(s):  
María Paula Quiroga ◽  
Andrea C Premoli ◽  
Cecilia Ezcurra
Keyword(s):  
Genetic Diversity ◽  
Natural Populations ◽  
Common Garden ◽  
High Elevation ◽  
Genetic Differences ◽  
Restricted Gene Flow ◽  
Common Garden Experiment ◽  
Southern Andes ◽  
Isozyme Electrophoresis ◽  
Ecotypic Variation

We tested the hypothesis that South Andean populations of the highly polymorphic and mostly Northern Hemisphere perennial forb Cerastium arvense L. show ecotypic variation along distinct habitats. We compared differences in morphology and flowering phenology among six natural populations occurring in different environments. Genetic differences were analyzed by a common-garden experiment and isozyme electrophoresis. Several of the morphological differences observed in the field were maintained after more than a year of cultivation in the common garden (e.g., plant height and leaf width). Mean tests and multivariate analyses on morphological traits generally distinguished high-elevation populations from the rest, and a similar grouping of populations was obtained from isozyme data at 10 loci. Cerastium arvense had genetic polymorphism levels of >50% in all populations and an average genetic diversity (HT = 0.254) of which approximately 20% was distributed among populations. These marked genetic differences are probably maintained by restricted gene flow due to variation in flowering time. Morphological and genetic differences suggest ecotypic variation in C. arvense in the southern Andes, which seems to have originated by disruptive selective pressures in different environments and the effect of genetic drift in response to the extreme climatic changes occurring during the Pleistocene.Key words: common-garden experiment, ecotypic variation, elevation and precipitation, genetic diversity, Patagonian Andes, phenology.

scholarly journals Biology and use of the Pacific fat sleeper Dormitator latifrons (Richardson, 1844): state of the art review

2021 ◽  
Vol 49 (3) ◽  
pp. 391-403
Author(s):  
Fernando Vega-Villasante ◽  
Luis E. Ruiz-González ◽  
Olimpia Chong-Carrillo ◽  
Mao E.R. Basto-Rosales ◽  
David J. Palma-Cancino ◽  
...  
Keyword(s):  
Latin America ◽  
Geographic Distribution ◽  
Fish Species ◽  
State Of The Art ◽  
Current Knowledge ◽  
Natural Populations ◽  
Systematic Research ◽  
Review Of The Literature ◽  
The Pacific ◽  
Cultivation Techniques

The present work is a review of the literature on the native Mexican fish Dormitator latifrons. The aim is to contribute to the integration and systematization of current knowledge to make it easier to identify existing knowledge gaps and breakthroghs Moreover, promote the successful cultivation and protection of this species whose consumption is increasing in Latin America. A review of the articles related to D. latifrons published in international and regional databases was carried out. The articles reviewed focus on taxonomy and systematics, phylogenetic, geographic distribution, ecology, physiology, reproduction, development, pathology, health, and the technologies used to cultivate this fish species. The conclusion is that, even though the cultivation of D. latifrons is of commercial interest in some countries, there are still significant gaps in our knowledge of biology and, consequently, the domestication potential of the species. Filling these gaps will require systematic research efforts on protecting natural populations and improving mass cultivation techniques.

Description of the biogeography of the Mymaridae Family (Insecta: Hymenoptera)

2021 ◽  
Vol 3 (1) ◽  
pp. 070-086
Author(s):  
Carlos Henrique Marchiori
Keyword(s):  
Life Cycle ◽  
Geographic Distribution ◽  
Literature Search ◽  
World Wide ◽  
Web Of Science ◽  
Health Sciences ◽  
Academic Science ◽  
Scientific Journals ◽  
Habitat Ecology ◽  
Microsoft Academic

The objective of this manuscript is to research the management, biology, habitat, ecology, geographic distribution, taxonomy, life cycle, phenology, parasitoidism (parasitism) of the Mymaridae Family (Insecta: Hymenoptera). The research was carried out in studies related to quantitative aspects taxonomic and conceptual aspects. A literature search was carried out containing articles published from 1984 to 2021. The mini review was prepared in Goiânia, Goiás, from September to October 2021. The mini-review was prepared in Goiânia, Goiás, from September to October 2021, through the Online Scientific Library (Scielo), internet, ResearchGate, Academia.edu, Frontiers, Biological Abstract, Publons, Qeios, Pubmed, Dialnet, World, Wide Science, Springer, RefSeek, Microsoft Academic, Science, ERIC, Science Research.com, SEEK education, Periodicals CAPES, Google Academic, Bioline International, VADLO, Scopus, Web of Science, LILACS, Medline, LIS and Portal of Scientific Journals in Health Sciences.

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