We investigated how the riverine network influences taxonomic and functional beta diversity patterns of fish assemblages in the mainstem/headwater (lateral) and upstream/downstream (longitudinal) ...gradients in a Neotropical river system. We investigated the following questions: which component (turnover or nestedness) explains taxonomic and functional beta diversity in both gradients? Is this component a consistent pattern for different lateral sections of the river basin? Is this component influenced by the spatial extent? Finally, how are taxonomic and functional beta diversity structured by space and environment along the longitudinal gradient? Taxonomic and functional turnover were the main patterns found for the lateral gradient and they were consistent for all lateral sections considered. Taxonomic and functional turnover were also the main patterns for the longitudinal gradient, increasing with the spatial extent increase and being structured by space and spatially structured environments. Our study demonstrates that the dendritic nature of riverine systems constrains species and traits occurrence along lateral and longitudinal gradients in a Neotropical region, generating taxonomic and functional turnover patterns due to the influence of space and spatially structured environments on niche- and dispersal-based processes. These results show that Neotropical riverine systems conservation must go beyond traditional approaches and consider the metacommunity perspective.
Teucrium montanum L. and T. capitatum L. are two plant species with overlapping distribution in the Balkan Peninsula, especially in Croatia, where several occurrences of their putative hybrid species ...T. × rohlenae have been recorded. Next-generation sequencing of both species and de novo assembly was carried out resulting in 120 contigs for T. montanum and 1685 contigs for T. capitatum assembled. The Dig-up primers pipeline was used for SSR mining of both assemblies, applying different criteria that resulted in 112 SSR candidates for testing. A subset of 41 SSRs was selected and after two rounds of testing, twelve SSRs were developed and characterized. A total of 232 alleles were detected with 5 to 29 alleles per locus, based on the test sample. The genetic diversity analysis of three Teucrium taxa from a single location revealed a higher level of diversity in T. montanum than in T. capitatum with intermediate values for the hybrid species. The NeighborNet diagram and genetic structure analysis grouped the taxa into two separate clusters, the first of which consisted exclusively of T. montanum, while the other was composed of intermixed T. capitatum and T. × rohlenae individuals. The availability of SSR markers for two Teucrium taxa will allow in-depth analysis of genetic diversity and structure, as well as molecular identification of their putative hybrids in the future.
Ilex chinensis Sims. is an evergreen tree species native to China and mainly distributed in the region south of the Qinling Mountains and the Huai River. This species has important ornamental, ...medicinal, ecological, and economic values, and plays a positive role in improving the environment and people’s lives. To reveal the genetic diversity and genetic structure of 401 individuals from 14 populations in the major distribution area of I. chinensis, 11 pairs of SSR primers were selected for PCR amplification. The products were then subjected to capillary electrophoresis, and the genetic diversity of Ilex individuals was analyzed using relevant software. The results showed that the genetic diversity of I. chinensis was at a moderate-to-high level. A total of 54 alleles were detected at 11 SSR loci in the 14 Ilex populations, with an average of 4.831 alleles per locus. AMOVA analysis indicated that the genetic variation of I. chinensis populations mainly originated within populations. A STRUCTURE analysis divided the 401 I. chinensis individuals into four different genetic clusters. The unweighted pair group methods using arithmetic averages (UPGMA) clustering based on Nei’s genetic distance revealed that the population from Xinping of Yuxi, Yunnan Province (XP), and the population from Longan of Qianxinan, Guizhou Province (LoA) were located in the outermost layer of the phylogenetic tree, indicating the furthest genetic relationship between these two population and other populations. The remaining populations could be roughly divided into two groups. Principal coordinate analysis (PCoA) demonstrated that the 401 individuals were clearly divided into three groups, which was consistent with the results of the STRUCTURE analysis and UPGMA clustering. This study identified the hotspots of genetic diversity of I. chinensis, as well as units for the conservation of individuals. It also revealed the patterns of genetic variation and population distribution of I. chinensis in different regions, providing a molecular basis for the geographical zoning and formulation of breeding programs for I. chinensis, as well as germplasm resource management.
In theoretical biology, a prevailing hypothesis posits a profound interconnection between effective population size (Nsub.e), genetic diversity, inbreeding, and genetic load. The domestication and ...improvement processes are believed to be pivotal in diminishing genetic diversity while elevating levels of inbreeding and increasing genetic load. In this study, we performed a whole genome analysis to quantity genetic diversity, inbreeding, and genetic load across seven wild Ovis species and five domesticated sheep breeds. Our research demonstrates that the genetic load and diversity of species in the genus Ovis have no discernible impact on recent Nsub.e, and three species within the subgenus Pachyceros tend to carry a higher genetic load and lower genetic diversity patterns. The results coincide with these species’ dramatic decline in population sizes within the subgenus Pachyceros ~80–250 thousand years ago. European mouflon presented with the lowest Nsub.e, lower genetic diversity, and higher individual inbreeding coefficient but a lower genetic load (missense and LoF). This suggests that the small Nsub.e of European mouflon could reduce harmful mutations compared to other species within the genus Ovis. We showed lower genetic diversity in domesticated sheep than in Asiatic mouflon, but counterintuitive patterns of genetic load, i.e., lower weak genetic load (missense mutation) and no significant difference in strong genetic load (LoF mutation) between domestic sheep and Asiatic mouflon. These findings reveal that the “cost of domestication” during domestication and improvement processes reduced genetic diversity and purified weak genetic load more efficiently than wild species.
This research is focused on the presence of the genus Diploneis (Bacillariopyta) in small lowland springs of north-eastern Poland. This study presents a biogeographic overview of the genus from 2 ...urban and 12 forest springs in the Podlasie area. Seven species were identified, some of which have been described recently and whose distribution is not well-known (D. burgitensis, D. fontium). The presence of D. burgitensis and D. parapetersenii, both rare taxa, are the first recorded for Poland. Their presence was confirmed using both LM and SEM micrographs. The presence of much more frequently noted European species (D. elliptica, D. fontanella, D. krammeri, and D. separanda) was also found. Greater knowledge of the Diploneis genus opens the way towards better and more comprehensive approaches to uncovering biological diversity and biogeographical patterns on the European continent and among the springs. The distribution of all recorded Diploneis species and their habitat preferences are briefly given.
The genetic diversity of 77 Trichoderma harzianum isolates collected from sunflower rhizosphere soils in Urmia, Khoy, and Salmas in West Azerbaijan province, Iran, was evaluated by using the ...Universal Rice Primer (URP) molecular marker. The DNA band pattern of the isolates was developed using seven primers of this marker. These primers produced 186 gene loci, out of which 182 loci were polymorphic. Accordingly, the genetic diversity of the isolates was calculated, and their kinship relations were determined by cluster analysis using the NTSYS software package. URP-6R had the highest marker index among the studied primers, followed by URP-1F, URP-4R, and URP-25F, implying their higher efficiency in discriminating between the isolates. The results showed that the URP marker could discriminate between isolates using macroscopic morphological characteristics, such as color and colony type, potential of pigment production in the culture medium, and colony growth rate. Furthermore, there was no significant relationship between the geographical distribution of the isolates and the band patterns generated by the primers except for a few cases. The results generally revealed that the URP marker was an efficient tool for determining the genetic diversity of T. harzianum.
Here, we present the newly identified Inosperma macrocarpa and the first record of I. afromelliolens from West Africa. Inosperma macrocarpa is nested in an Old World Tropical clade, based on a ...molecular phylogeny inferred from the sequences of ITS, LSU, RPB2, and TEF1. Complete descriptions and illustrations, including photographs and line drawings, of the new species are presented. Morphological and molecular analyses based on collections from Benin confirmed the presence of I. afromelliolens in West Africa. Toxicity analysis showed that neither species contained muscarine, which further supports the hypothesis that the ability to produce muscarine is a derived trait of Inosperma.
Water yam (Dioscorea alata L.) is among the most cultivated species used as a source of food and income for small-scale farmers in Tanzania. However, little is documented about Dioscorea species ...available in Tanzania, including their genetic diversity. This study used ten polymorphic microsatellite markers to determine the genetic diversity and relationship of 63 D. alata accessions from six major producing regions. Results revealed a polymorphic information content (PIC) of 0.63, while the number of alleles per locus ranged from 4 to 12 with a mean of 7.60. The expected heterozygosity ranged from 0.20to 0.76, with a mean of 0.53, which suggests moderate genetic diversity of D. alata accessions. Kagera region had the highest mean number of (1.5) private alleles. Analysis of molecular variance revealed that 54% of the variation was attributed to within individual, 39% was attributed to among individual while among population contributed 7% of the total variation. The highest Nei's genetic distance (0.43) was for accessions sampled from Kilimanjaro and Mtwara regions. Principal coordinate analysis and cluster analysis using Unweighted Paired Group Method using Arithmetic (UPGMA) grouped D. alata accessions into two major clusters regardless of geographical origin and local names. The Bayesian structure analysis confirmed the two clusters obtained in UPGMA and revealed an admixture of D. alata accessions in all six regions suggesting farmers' extensive exchange of planting materials. These results are helpful in the selection of D. alata accessions for breeding programs in Tanzania.
Otoliths of Caspian gobies Zarei, Fatah; Esmaeili, Hamid Reza; Stepien, Carol A ...
PloS one,
05/2023, Letnik:
18, Številka:
5
Journal Article
Recenzirano
Otoliths (ear stones) of the inner ears of teleost fishes, which develop independently from the skeleton and are functionally associated with hearing and the sense of equilibrium, have significantly ...contributed to contemporary understanding of teleost fish systematics and evolutionary diversity. The sagittal otolith is of particular interest, since it often possesses distinctive morphological features that differ significantly among species, and have been shown to be species- and genus-specific, making it an informative taxonomic tool for ichthyologists. The otolith morphology of the Caspian Sea gobiids has not been thoroughly studied yet, with data available for only a few species. The aim of the present paper is to examine the qualitative and quantitative taxonomic and phylogenetic information in the sagittal otoliths of these species. A total of 118 otoliths representing 30 gobiid species (including 53.5% of the Caspian gobiofauna) in three gobiid lineages (i.e., Gobius, Pomatoschistus, and Acanthogobius) and 11 genera (i.e., all Ponto-Caspian gobiid genera except Babka) were analysed at taxonomic levels using an integrated descriptive and morphometric approach. The results indicated high taxonomic efficiency of otolith morphology and morphometry at taxonomic levels for the Ponto-Caspian gobiids. Our qualitative and quantitative otolith data also (i) support the monophyly of neogobiin gobies, (ii) along with other morphological and ecological data, offer a new perspective on the systematics of Neogobius bathybius, (iii) suggest the reassignment of Hyrcanogobius bergi to the genus Knipowitschia, and (iv) question the phylogenetic integrity of the four phenotypic groups previously defined in the tadpole-goby genus Benthophilus; however, more studies are needed to complete these evaluations and confirm our otolith study findings.
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