Taxonomic evaluation of Miscanthus nudipes (Poaceae) based on morphological and molecular evidence

Phytotaxa ◽  
2015 ◽  
Vol 205 (1) ◽  
pp. 1 ◽  
Author(s):  
Hong-Zheng Ma ◽  
Zhe Cai ◽  
Fu-Min Zhang ◽  
Hui Zhang ◽  
Song Ge ◽  
...  
Keyword(s):  
Natural Populations ◽  
Morphological Characters ◽  
Population Variation ◽  
Distribution Area ◽  
Molecular Evidence ◽  
Hengduan Mountains ◽  
Important Species ◽  
Taxonomic Treatment ◽  
Variation Patterns ◽  
Energy Plant

Miscanthus species including the famous energy plant M. × giganteus are considered to be second-generation energy crops. Miscanthus nudipes is an endemic species from Himalaya-Hengduan Mountains and provides important germplasm for Miscanthus breeding given its high tolerance to frost and drought. However, the taxonomy of this species remains controversial in terms of intraspecific classification, with one to nine subspecies or species recognized previously. The variation patterns of the morphological characters are not understood clearly as there have been no intensive analyses of the morphological variation across individuals and populations. Here, by sampling 15 natural populations from the entire distribution area of M. nudipes, we investigate patterns of population variation based on 39 quantitative and nine qualitative morphological characters and 14 microsatellite loci, with the aim to provide a reliable taxonomic treatment of this important species. Morphological analyses from ANOVA, UPGMA and PCA indicate that M. nudipes populations show significant differences between the Himalayas and Hengduan Mountains. A neighbor-joining tree and principle coordinates analysis of the microsatellite data support the results of the morphological analyses. Based on our results, we recognize two subspecies under Miscanthus nudipes (M. nudipes subsp. nudipes and M. nudipes subsp. yunnanensis) and provide a taxonomic treatment for the species. We propose three diagnostic characters for the subspecies identification, i.e., the ratio of callus hair length to spikelet length, the hairiness of the panicle axis and the hairiness of the peduncle.

scholarly journals Does selection or genetic drift explain geographic differentiation of morphological characters in house sparrowsPasser domesticus?

2011 ◽  
Vol 93 (5) ◽  
pp. 367-379 ◽  
Author(s):  
ANNA M. HOLAND ◽  
HENRIK JENSEN ◽  
JARLE TUFTO ◽  
RUNE MOE
Keyword(s):  
Genetic Differentiation ◽  
Genetic Drift ◽  
Quantitative Trait ◽  
Evolutionary Biology ◽  
Additive Genetic Variance ◽  
Natural Populations ◽  
Passer Domesticus ◽  
Morphological Characters ◽  
Relative Magnitude ◽  
Population Variation

SummaryUnderstanding the relative influence of genetic drift and selection is fundamental in evolutionary biology. The theory of neutrality predicts that the genetic differentiation of a quantitative trait (QST) equals the genetic differentiation at neutral molecular markers (FST) if the quantitative trait has not been under selection. Thus, the relative magnitude of observedQSTand expectedQSTunder neutral expectations suggests the importance of selection and genetic drift for any observed phenotypic divergence. BecauseQSTis based on additive genetic variance, estimatingQSTbased on phenotypic measurements is problematic due to unknown environmental effects. To account for this, we used a model where the environmental component was allowed to vary when estimatingQST. The model was used on data from 14 house sparrow (Passer domesticus) populations in Norway. In accordance with the significant phenotypic inter-population differences our analyses suggested that directional selection may have favoured different optimal phenotypes for some morphological traits across populations. In particular, different body mass and male ornamental phenotypes seemed to have been favoured. The conclusions are, however, dependent on assumptions regarding the proportion of the observed inter-population variation that is due to additive genetic differences, showing the importance of collecting such information in natural populations. By estimatingQST, allowing the additive genetic proportion of phenotypic inter-population variation to vary, and by making use of recent statistical methods to compare observedQSTwith neutral expectations, we can use data that are relatively easy to collect to identify adaptive variation in natural populations.

ITS sequence variation supports the hybrid origin of Malus toringoides Hughes

2007 ◽  
Vol 85 (7) ◽  
pp. 659-666 ◽  
Author(s):  
Ting-Ting Feng ◽  
Zhi-Qin Zhou ◽  
Jian-Min Tang ◽  
Ming-Hao Cheng ◽  
Shi-Liang Zhou
Keyword(s):  
Sequence Variation ◽  
Gene Tree ◽  
Natural Populations ◽  
Its Sequences ◽  
Nuclear Ribosomal Dna ◽  
Hybrid Origin ◽  
Putative Hybrid ◽  
Molecular Evidence ◽  
Sequence Information ◽  
Aflp Data

Malus toringoides (Rehd.) Hughes was suggested to have originated from hybridization between Malus transitoria Schneid. and Malus kansuensis Rehd., followed by repeated backcrossing to one of the putative parents. In the present study, the sequence information of the internal transcribed spacer (ITS) of nuclear ribosomal DNA (nrDNA) was used to re-examine the origin of this species. A total of 69 accessions from three natural populations (Maerkang, Xiaba and Kehe, Aba Autonomous Region, Sichuan, China) of M. toringoides and 10 accessions of its putative parents were analyzed. Using Malus angustifolia (Ait.) Michx., Malus ioensis (Wood) Britt. and Malus doumeri Chev. as outgroups, our phylogenetic analysis of the ITS sequences of M. toringoides and its putative parents showed that M. toringoides was not monophyletic, and two different types of ITS sequences which were obtained from each of the six accessions of M. toringoides were found to have clustered separately with those of the two putative parent species on the gene tree. A comparison of the sequence variation between M. toringoides and its putative parents revealed an additive variation pattern of ITS sequences in the putative hybrid species. These results are consistent with the previous morphological and amplified fragment length polymorphism (AFLP) data which suggested that M. toringoides was of hybrid origin. Our ITS data provide new molecular evidence for the hybrid origin hypothesis of M. toringoides and these results are of great importance for future study on hybridization, polyploid speciation and evolution of the genus Malus Miller.

Molecular Evidence of Wolbachia Infection in Natural Populations of Tropical Odonates

2003 ◽  
Vol 47 (4) ◽  
pp. 314-318 ◽  
Author(s):  
Apisit Thipaksorn ◽  
Wanwisa Jamnongluk ◽  
Pattamaporn Kittayapong
Keyword(s):  
Natural Populations ◽  
Wolbachia Infection ◽  
Molecular Evidence

Molecular evidence for the hybrid origin of Rosa lichiangensis (Rosaceae)

Phytotaxa ◽  
2015 ◽  
Vol 222 (3) ◽  
pp. 221 ◽  
Author(s):  
Zhangming Zhu ◽  
Xinfen Gao
Keyword(s):  
Significant Role ◽  
Single Copy ◽  
Morphological Characters ◽  
Molecular Data ◽  
Natural Hybridization ◽  
Hybrid Origin ◽  
Molecular Evidence ◽  
Nuclear Marker

Natural hybridization was assumed to play a significant role in the diversification of Rosa. Rosa lichiangensis was suspected to be of hybrid origin based on its intermediate morphological characters between R. soulieana and R. multiflora var. cathayensis. In this study, four chloroplast regions (ndhC-trnV, ndhF-rpl32, ndhJ-trnF, and psbJ-petA) and a single copy nuclear marker (GAPDH) were used to test the hybrid origin of R. lichiangensis. The results from molecular data supported the hybrid origin of R. lichiangensis and further identified R. soulieana as its maternal progenitor and R. multiflora var. cathayensis as the paternal progenitor.

Variability in Island Populations of the House Finch

The Auk ◽  
1983 ◽  
Vol 100 (1) ◽  
pp. 180-187 ◽  
Author(s):  
Dennis M. Power
Keyword(s):  
Morphological Characters ◽  
Population Variation ◽  
Carpodacus Mexicanus ◽  
House Finch ◽  
Isolated Populations ◽  
Island Populations ◽  
Coefficients Of Variation ◽  
Variation Parameter ◽  
Guadalupe Island

Abstract Coefficients of variation and generalized variances are compared for nine morphological characters from five mainland and four island populations of the House Finch (Carpodacus mexicanus). The purpose is to test the idea that variability is reduced in isolated populations and that there is a "population variation parameter" that determines the level of variation in most characters. Variability is greater in bill characters for Guadalupe and San Benito Islands than for mainland and other island populations. There are no consistent differences among samples in variability of wing, tail, or hind-limb characters, except for a tendency toward increased tarsus-length variability in a southern Baja California population and reduced variability in this character in San Clemente Island and Guadalupe Island populations. In bill characters, increased variability is found in the most divergent populations. The results do not support the generalization that geographic (= genetic) isolation per se causes much of a change in variability in island populations of birds, nor is there support for the idea of a pervasive quality of the gene pool that determines the level of variability in most characters.

Phylogenetics of the mycoheterotrophic genus Thismia (Thismiaceae: Dioscoreales) with a focus on the Old World taxa: delineation of novel natural groups and insights into the evolution of morphological traits

2020 ◽  
Vol 193 (3) ◽  
pp. 287-315 ◽  
Author(s):  
Ekaterina A Shepeleva ◽  
Mikhail I Schelkunov ◽  
Michal Hroneš ◽  
Michal Sochor ◽  
Martin Dančák ◽  
...  
Keyword(s):  
Significant Proportion ◽  
Morphological Diversity ◽  
Taxonomic Revision ◽  
Morphological Characters ◽  
Morphological Description ◽  
Molecular Evidence ◽  
Ancestral State ◽  
Old World ◽  
Molecular Phylogenetic ◽  
Floral Characters

Abstract Thismia is a genus of > 80 mycoheterotrophic species characterized by a peculiar appearance and complex floral morphology. A significant proportion of the species and morphological diversity of Thismia has only been uncovered in the past two decades, and new discoveries continue to be made. Given that many new data have recently become available, and the most comprehensive taxonomic revision of the genus from 1938 addresses less than half of the currently known species, previous hypotheses for species relationships and infrageneric taxonomic classification in Thismia was in need of review. Extensive molecular phylogenetic studies of Thismia at the genus level have never been presented. We investigate the phylogenetic relationships of 41 species (and one variety) of Thismia from the Old World. Our study comprises 68 specimens (for 28 of which the data were newly generated), including outgroup taxa broadly representing Thismiaceae (= Burmanniaceae p.p. sensuAPG IV, 2016), and is based on two nuclear and one mitochondrial marker. We use maximum likelihood and Bayesian inference to infer relationships among the taxa. We also constructed a morphological dataset of 12 mostly floral characters, comparing these characters to hypotheses based on molecular evidence to identify putative synapomorphies for major clades and to discuss hypotheses regarding the evolution of structural traits in the genus. Our analyses indicate that the majority of currently accepted infrageneric taxa of Thismia are polyphyletic. We find support for the monophyly of the Old World group, in which we recognize five well-supported lineages (clades); the only New World species studied appears to be related to the Neotropical genus Tiputinia. Ancestral state reconstructions demonstrate that the evolution of most morphological characters was homoplastic, but we identify characters that provide each of the five clades of Old World Thismia with a unique morphological description. The geographical distribution of the species under study is also shown to be consistent with the major clades. Our investigation provides a phylogenetic basis for the development of a novel sectional classification of Thismia reflecting morphological and geographical traits.

Three new species of Bathysciola Jeannel, 1910 (Leiodidae, Cholevinae, Leptodirini) from caves in Central Italy, comparing morphological taxonomy with molecular phylogeny

2018 ◽  
Vol 49 (4) ◽  
pp. 409-442 ◽  
Author(s):  
Leonardo Latella ◽  
Valerio Sbordoni ◽  
Giuliana Allegrucci
Keyword(s):  
Geographic Distribution ◽  
Phylogenetic Signal ◽  
Central Italy ◽  
Morphological Characters ◽  
Species Group ◽  
Distribution Area ◽  
12S Rrna ◽  
Historical Processes ◽  
Italian Apennines ◽  
Three New Species

The genus Bathysciola is widely distributed in the northern Mediterranean region, although its range extends east to the Caucasus and Iran. More than 130 species belonging to this genus are actually known in the whole geographic distribution area and 45 species are distributed in continental and insular Italy. The species belonging to the Bathysciola sisernica Cerruti and Patrizi, 1952 species group occur in the Central-Southern Italian Apennines and Pre-Apennines. This group consists of seven species, four of which (B. sisernica, B. delayi Latella and Rampini, 1994, B. rampinii Latella, 2002, B. sbordoni Rampini and Latella, 1993) were already known to science and three are described herein, Bathysciola fabiolae sp. nov., Bathysciola octaviani sp. nov. , and Bathysciola valeriae sp. nov., markedly increasing the knowledge on the distribution of this genus in Central Italy. A morphological analysis was carried out based on diagnostic characters usually used to distinguish different taxa, and including both genitalia and external traits. Based on morphological characters, we reconstructed the phylogeny of this group of species, comparing them with the species belonging to other phyletic lineages, such as B. derosasi Jeannel, 1914, B. georgi Cerruti, Patrizi, 1952, B. vignai Sbordoni and Rampini, 1978, and B. sarteanensis sarteanensis (Bargagli, 1870). Results suggested that morphological traits show a clear taxonomic signal but a poor phylogenetic signal. To better understand the relationships within this group of species, we performed a molecular analysis by sequencing three mitochondrial genes, 12S rRNA, 16S rRNA, partially sequenced and the entire gene of COI. Molecular markers were used to infer phylogenetic relationships among the Bathysciola sisernica species group and to reconstruct the historical processes that shaped their current geographic distribution. Results showed that these species became isolated in very ancient times, showing very high genetic differentiation.

Taxonomic status of Clematis acerifolia var. elobata, based on molecular evidence

Phytotaxa ◽  
2016 ◽  
Vol 268 (3) ◽  
pp. 209 ◽  
Author(s):  
SHUANG-XI YAN ◽  
HUI-JIE LIU ◽  
LE-LE LIN ◽  
SHUAI LIAO ◽  
JIN-YU LI ◽  
...  
Keyword(s):  
Taxonomic Status ◽  
Species Level ◽  
Distribution Area ◽  
Molecular Evidence ◽  
Discrimination Power ◽  
Nuclear Its ◽  
The Mean ◽  
Morphological Differences ◽  
The Relationship ◽  
Better Than

The morphologically based taxonomic status of Clematis acerifolia var. elobata has been controversial. This study used two nuclear (ITS and ETS) and six plastid (rps16, rpl16, accD, trnS-trnG, atpB-rbcL, and trnV-atpE) molecular markers, and a DNA barcoding analysis to address the taxonomic status of C. acerifolia var. elobata and the relationship among other Clematis species. Our results showed that the discrimination power of ITS, ETS, and atpB-rbcL was better than that of the other tested DNA regions. When all tested sequences combined, most of the sampled taxa were resolved. Though the two taxa are closely related, they have differentiated clearly and formed two clades respectively. The mean divergence of the two taxa was 0.78%, which was higher than closely related Clematis species such as C. heracleifolia and C. pinnata (0.50 %). Considering molecular divergence, morphological differences, and distribution area, we raised C. acerifolia var. elobata to species level.

scholarly journals A quantitative genetic study of starvation resistance at different geographic scales in natural populations of Drosophila melanogaster

2010 ◽  
Vol 92 (4) ◽  
pp. 253-259 ◽  
Author(s):  
JULIETA GOENAGA ◽  
JUAN JOSÉ FANARA ◽  
ESTEBAN HASSON
Keyword(s):  
Drosophila Melanogaster ◽  
Genetic Correlations ◽  
Natural Populations ◽  
Food Shortage ◽  
Population Variation ◽  
Phenotypic Variance ◽  
Starvation Resistance ◽  
Natural Genetic Variation ◽  
Quantitative Genetic ◽  
Variation Explained

SummaryFood shortage is a stress factor that commonly affects organisms in nature. Resistance to food shortage or starvation resistance (SR) is a complex quantitative trait with direct implications on fitness. However, surveys of natural genetic variation in SR at different geographic scales are scarce. Here, we have measured variation in SR in sets of lines derived from nine natural populations of Drosophila melanogaster collected in western Argentina. Our study shows that within population variation explained a larger proportion of overall phenotypic variance (80%) than among populations (7·2%). We also noticed that an important fraction of variation was sex-specific. Overall females were more resistant to starvation than males; however, the magnitude of the sexual dimorphism (SD) in SR varied among lines and explained a significant fraction of phenotypic variance in all populations. Estimates of cross-sex genetic correlations suggest that the genetic architecture of SR is only partially shared between sexes in the populations examined, thus, facilitating further evolution of the SD.

A new species of Antrodia (Basidiomycota, Polyporales) from juniper forest of Uzbekistan

Phytotaxa ◽  
2017 ◽  
Vol 303 (1) ◽  
pp. 47 ◽  
Author(s):  
YUAN YUAN ◽  
YUSUFJON GAFFOROV ◽  
YUAN-YUAN CHEN ◽  
FANG WU
Keyword(s):  
New Species ◽  
Arid Regions ◽  
Large Subunit ◽  
Brown Rot ◽  
Morphological Characters ◽  
Molecular Evidence ◽  
Distinct Lineage ◽  
Large Subunit Rdna ◽  
A New Species ◽  
Semi Arid

Antrodia uzbekistanica sp. nov. is described and illustrated from juniper trees in Uzbekistan based on morphological characters and molecular evidence. It is characterized by producing annual, resupinate basidiome with large pores (1–2 per mm), a dimitic hyphal structure with clamp connections on generative hyphae, hyaline, thin-walled and cylindric basidiospores (6.5–8 × 2.7–3 µm), the presence of thick-walled and cyanophilous chlamydospores, and by causing a typical brown rot of Juniperus seravschanica in arid and semi-arid regions of Uzbekistan. The new species resembles Antrodia sinuosa macroscopically, but this species differs by having smaller basidiospores (4–6 × 1–2 µm), lacking of chlamydospores, and growing on wood of Pinaceae species. In nuclear large subunit rDNA (nLSU) and internal transcribed spacer (ITS) based phylogenies, the new species formed a distinct lineage in the Antrodia clade, and it is closely related to A. juniperina, which differs by having perennial, effused-reflexed basidiome with nodulose or round edged pilei, daedaleoid to labyrinthine pores, and larger and narrowly ellipsoid basidiospores (6.5–9 × 2.5–3.5 µm).

Sign in / Sign up

Export Citation Format

Share Document