Analysis of a polyploid complex in Glycine with chloroplast and nuclear DNA

1990 ◽  
Vol 3 (1) ◽  
pp. 125 ◽  
Author(s):  
JJ Doyle ◽  
JL Doyle ◽  
AHD Brown

Studies of chloroplast DNA and nuclear 18s–25s ribosomal genes have revealed considerable variation in Glycine subgenus Glycine, the perennial relatives of the cultivated annual soybean. We have used these molecular characters to investigate the origins and evolution of G. tabacina, a species that comprises a widespread polyploid complex in Australia and the islands of the southern and west-central Pacific. Two principal groups of accessions were detected in this species using molecular characters. These two types also differ morphologically and have distinct, though overlapping, geographic ranges; comparison with results of artificial hybridisation studies showed that sterility barriers exist between the two groups. Both types are fixed hybrids for nuclear rDNA, and share one rDNA repeat class, presumably derived from a common diploid progenitor. The two types had different maternal progenitors, based on cpDNA variation. One of the two polyploid types is polymorphic for cpDNA, and shares nearly all of its plastome variants with diploid accessions, suggesting multiple, independent origins of the polyploid from a pool of diploid progenitors. Molecular data suggest that polyploids have originated recently, and that dispersal from Australia to the islands of the Pacific has occurred several times.

2010 ◽  
Vol 23 (3) ◽  
pp. 162 ◽  
Author(s):  
Gillian K. Brown ◽  
Catherine Clowes ◽  
Daniel J. Murphy ◽  
Pauline Y. Ladiges

Seventeen Australian, phyllodinous species of Acacia s.s. (from sections Juliflorae and Phyllodineae) were analysed to test the monophyly and relationships of ‘the Acacia longifolia group’, an informal group recognised in the Flora of Australia. Analyses were based on both morphological and molecular data, with A. triptera as an outgroup. A total of 92 herbarium specimens was investigated, with 15 phyllode, inflorescence, flower, pod and seed characters scored. The ITS and ETS regions of nuclear rDNA were sequenced and combined with a larger dataset sampled from species of all major clades of Acacia, totalling 65 accessions. Cladistic analyses provided evidence of a clade that defines the A. longifolia group as follows: A. alpina, A. axillaris, A. courtii, A. dallachiana, A. derwentiana, A. floribunda, A. longifolia subsp. longifolia and A. longifolia subsp. sophorae, A. longissima, A. maidenii, A. mucronata, A. obtusifolia, A. orites, A. oxycedrus, A. phlebophylla, A. rhigiophylla and A. riceana (all sect. Juliflorae), but excluding A. verticillata (section Juliflorae) and A. genistifolia (section Phyllodineae). The A. longifolia group is recognised as including south-eastern Australian species with cylindrically spiked inflorescences and phyllodes with prominent anastomosing venation.


Botany ◽  
2013 ◽  
Vol 91 (2) ◽  
pp. 107-116 ◽  
Author(s):  
E.Y.Y. Lo ◽  
S. Stefanović ◽  
T.A. Dickinson

We have demonstrated geographical parthenogenesis in Crataegus series Douglasianae, an agamic complex comprising exclusively tetraploid Crataegus douglasii sensu lato and the morphologically distinct Crataegus suksdorfii complex that comprises diploids and polyploids. Here we characterize ploidy level and breeding system by detailed flow cytometric measurements of the 2C nuclear DNA content of leaf, embryo, and endosperm tissues from 282 black-fruited hawthorns (Crataegus series Douglasianae) representing 33 localities in the Pacific Northwest, one in the Cypress Hills, and three more in the upper Great Lakes basin. We use existing climate and molecular data to place our flow cytometry results in an environmental and evolutionary context. Crataegus douglasii occupies more widely distributed sites that experience more extreme temperature and moisture regimes than do the sites occupied by diploid C. suksdorfii.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Koji Takayama ◽  
Yoichi Tateishi ◽  
Tadashi Kajita

AbstractRhizophora is a key genus for revealing the formation process of the pantropical distribution of mangroves. In this study, in order to fully understand the historical scenario of Rhizophora that achieved pantropical distribution, we conducted phylogeographic analyses based on nucleotide sequences of chloroplast and nuclear DNA as well as microsatellites for samples collected worldwide. Phylogenetic trees suggested the monophyly of each AEP and IWP lineages respectively except for R. samoensis and R. × selala. The divergence time between the two lineages was 10.6 million years ago on a dated phylogeny, and biogeographic stochastic mapping analyses supported these lineages separated following a vicariant event. These data suggested that the closure of the Tethys Seaway and the reduction in mangrove distribution followed by Mid-Miocene cooling were key factors that caused the linage diversification. Phylogeographic analyses also suggested the formation of the distinctive genetic structure at the AEP region across the American continents around Pliocene. Furthermore, long-distance trans-pacific dispersal occurred from the Pacific coast of American continents to the South Pacific and formed F1 hybrid, resulting in gene exchange between the IWP and AEP lineages after 11 million years of isolation. Considering the phylogeny and phylogeography with divergence time, a comprehensive picture of the historical scenario behind the pantropical distribution of Rhizophora is updated.


Phytotaxa ◽  
2014 ◽  
Vol 176 (1) ◽  
pp. 219 ◽  
Author(s):  
ASHA J. DISSANAYAKE ◽  
RUVISHIKA S. JAYAWARDENA ◽  
SARANYAPHAT BOONMEE ◽  
KASUN M. THAMBUGALA ◽  
QING TIAN ◽  
...  

The family Myriangiaceae is relatively poorly known amongst the Dothideomycetes and includes genera which are saprobic, epiphytic and parasitic on the bark, leaves and branches of various plants. The family has not undergone any recent revision, however, molecular data has shown it to be a well-resolved family closely linked to Elsinoaceae in Myriangiales. Both morphological and molecular characters indicate that Elsinoaceae differs from Myriangiaceae. In Elsinoaceae, small numbers of asci form in locules in light coloured pseudostromata, which form typical scab-like blemishes on leaf or fruit surfaces. The coelomycetous, “Sphaceloma”-like asexual state of Elsinoaceae, form more frequently than the sexual state; conidiogenesis is phialidic and conidia are 1-celled and hyaline. In Myriangiaceae, locules with single asci are scattered in a superficial, coriaceous to sub-carbonaceous, black ascostromata and do not form scab-like blemishes. No asexual state is known. In this study, we revisit the family Myriangiaceae, and accept ten genera, providing descriptions and discussion on the generic types of Anhellia, Ascostratum, Butleria, Dictyocyclus, Diplotheca, Eurytheca, Hemimyriangium, Micularia, Myriangium and Zukaliopsis. The genera of Myriangiaceae are compared and contrasted. Myriangium duriaei is the type species of the family, while Diplotheca is similar and may possibly be congeneric. The placement of Anhellia in Myriangiaceae is supported by morphological and molecular data. Because of similarities with Myriangium, Ascostratum (A. insigne), Butleria (B. inaghatahani), Dictyocyclus (D. hydrangea), Eurytheca (E. trinitensis), Hemimyriangium (H. betulae), Micularia (M. merremiae) and Zukaliopsis (Z. amazonica) are placed in Myriangiaceae. Molecular sequence data from fresh collections is required to confirm the relationships and placement of the genera in this family.


Terra Nova ◽  
2008 ◽  
Vol 20 (3) ◽  
pp. 246-251 ◽  
Author(s):  
Martin Meschede ◽  
Udo Barckhausen ◽  
Martin Engels ◽  
Wilhelm Weinrebe

2010 ◽  
Vol 67 (10) ◽  
pp. 3097-3112 ◽  
Author(s):  
Katrina S. Virts ◽  
John M. Wallace

Abstract Cloud fields based on the first three years of data from the Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) mission are used to investigate the relationship between cirrus within the tropical tropopause transition layer (TTL) and the Madden–Julian oscillation (MJO), the annual cycle, and El Niño–Southern Oscillation (ENSO). The TTL cirrus signature observed in association with the MJO resembles convectively induced, mixed Kelvin–Rossby wave solutions above the Pacific warm pool region. This signature is centered to the east of the peak convection and propagates eastward more rapidly than the convection; it exhibits a pronounced eastward tilt with height, suggestive of downward phase propagation and upward energy dispersion. A cirrus maximum is observed over equatorial Africa and South America when the enhanced MJO-related convection enters the western Pacific. Tropical-mean TTL cirrus is modulated by the MJO, with more than twice as much TTL cirrus fractional coverage equatorward of 10° latitude when the enhanced convection enters the Pacific than a few weeks earlier, when the convection is over the Indian Ocean. The annual cycle in cirrus clouds around the base of the TTL is equatorially asymmetric, with more cirrus observed in the summer hemisphere. Higher in the TTL, the annual cycle in cirrus clouds is more equatorially symmetric, with a maximum in the boreal winter throughout most of the tropics. The ENSO signature in TTL cirrus is marked by a zonal shift of the peak cloudiness toward the central Pacific during El Niño and toward the Maritime Continent during La Niña.


2011 ◽  
Vol 43 (5) ◽  
pp. 427-444 ◽  
Author(s):  
Lauri SAAG ◽  
Tiiu TÕRRA ◽  
Andres SAAG ◽  
Ruth DEL-PRADO ◽  
Tiina RANDLANE

AbstractThis study focuses on EuropeanUsneaspecies with sorediate shrubby thalli, with the aim to evaluate the morphological and chemical separation of species in the light of molecular data. Twenty-twoUsneaspecies, including widely distributed taxa such asU. diplotypus, U. fulvoreagens, U. glabrescens, U. lapponica, U. subfloridana, U. substerilisandU. wasmuthii, were included in the study using Bayesian and maximum parsimony analyses of nuclear ITS and beta-tubulin sequences. The analyses showed that: 1) most taxa that are morphologically well delimited are also distinct by means of molecular characters, 2) shrubby taxa in the sectionUsneathat are difficult to determine by traditional characters form a group of closely related but still genetically distinct entities, exceptU. diplotypusandU. substeriliswhich appear to be polyphyletic. The branch lengths differed largely between two parts of the ITS tree (sectionsUsneaandCeratinae).Usnea intermediais proposed as the sexually reproducing counterpart for the sorediateU. lapponica. Additionally, some new chemotypes ofUsneaspecies were determined.


2017 ◽  
Vol 17 (14) ◽  
pp. 9081-9102 ◽  
Author(s):  
Michael J. Prather ◽  
Xin Zhu ◽  
Clare M. Flynn ◽  
Sarah A. Strode ◽  
Jose M. Rodriguez ◽  
...  

Abstract. An approach for analysis and modeling of global atmospheric chemistry is developed for application to measurements that provide a tropospheric climatology of those heterogeneously distributed, reactive species that control the loss of methane and the production and loss of ozone. We identify key species (e.g., O3, NOx, HNO3, HNO4, C2H3NO5, H2O, HOOH, CH3OOH, HCHO, CO, CH4, C2H6, acetaldehyde, acetone) and presume that they can be measured simultaneously in air parcels on the scale of a few km horizontally and a few tenths of a km vertically. As a first step, six global models have prepared such climatologies sampled at the modeled resolution for August with emphasis on the vast central Pacific Ocean basin. Objectives of this paper are to identify and characterize differences in model-generated reactivities as well as species covariances that could readily be discriminated with an unbiased climatology. A primary tool is comparison of multidimensional probability densities of key species weighted by the mass of such parcels or frequency of occurrence as well as by the reactivity of the parcels with respect to methane and ozone. The reactivity-weighted probabilities tell us which parcels matter in this case, and this method shows skill in differentiating among the models' chemistry. Testing 100 km scale models with 2 km measurements using these tools also addresses a core question about model resolution and whether fine-scale atmospheric structures matter to the overall ozone and methane budget. A new method enabling these six global chemistry–climate models to ingest an externally sourced climatology and then compute air parcel reactivity is demonstrated. Such an objective climatology containing these key species is anticipated from the NASA Atmospheric Tomography (ATom) aircraft mission (2015–2020), executing profiles over the Pacific and Atlantic Ocean basins. This modeling study addresses a core part of the design of ATom.


2021 ◽  
Vol 99 (2) ◽  
pp. 398-412
Author(s):  
Marcelo R. Pace ◽  
Brenda Hernández-Hernández ◽  
Esteban M. Martínez Salas ◽  
Lúcia G. Lohmann ◽  
N. Ivalu Cacho

Background: Astianthus is a monospecific arborescent genus of Bignoniaceae that occur in the Pacific Coast of central Mexico and northern Central America, where it grows in dense populations along riversides. Its phylogenetic placement has remained controversial since Astianthus has unusual morphological characters such as a four-loculed ovary, and simple, pulvinate, verticillate leaves. Methods: Here we used three plastid markers ndhF, rbcL, and trnL-F, wood, and bark anatomical data to investigate the phylogenetic placement of Astianthus and assign it to one of Bignoniaceae’s main clades. Results: Our molecular phylogenetic analyses indicated that Astianthus belongs in tribe Tecomeae s.s., where other charismatic Neotropical Bignoniaceae genera such as Campsis and Tecoma are currently placed. Wood and bark anatomy support this placement, as Astianthus reunites a unique combination of features only known from members of Tecomeae s.s., such as storied axial parenchyma, the co-occurrence of homo- and heterocellular rays, septate fibers, and scattered phloem fibers in the bark. Conclusions: The placement of Astianthus within Tecomeae s.s. provides further support to previous proposals for the Neotropical origin of this Pantropical tribe.


2006 ◽  
Vol 134 (12) ◽  
pp. 3567-3587 ◽  
Author(s):  
Linda M. Keller ◽  
Michael C. Morgan ◽  
David D. Houghton ◽  
Ross A. Lazear

Abstract A climatology of large-scale, persistent cyclonic flow anomalies over the North Pacific was constructed using the National Centers for Environmental Prediction–National Center for Atmospheric Research (NCEP–NCAR) global reanalysis data for the cold season (November–March) for 1977–2003. These large-scale cyclone (LSC) events were identified as those periods for which the filtered geopotential height anomaly at a given analysis point was at least 100 m below its average for the date for at least 10 days. This study identifies a region of maximum frequency of LSC events at 45°N, 160°W [key point 1 (KP1)] for the entire period. This point is somewhat to the east of regions of maximum height variability noted in previous studies. A second key point (37.5°N, 162.5°W) was defined as the maximum in LSC frequency for the period after November 1988. The authors show that the difference in location of maximum LSC frequency is linked to a climate regime shift at about that time. LSC events occur with a maximum frequency in the period from November through January. A composite 500-hPa synoptic evolution, constructed relative to the event onset, suggests that the upper-tropospheric precursor for LSC events emerges from a quasi-stationary long-wave trough positioned off the east coast of Asia. In the middle and lower troposphere, the events are accompanied by cold thickness advection from a thermal trough over northeastern Asia. The composite mean sea level evolution reveals a cyclone that deepens while moving from the coast of Asia into the central Pacific. As the cyclone amplifies, it slows down in the central Pacific and becomes nearly stationary within a day of onset. Following onset, at 500 hPa, a stationary wave pattern, resembling the Pacific–North American teleconnection pattern, emerges with a ridge immediately downstream (over western North America) and a trough farther downstream (from the southeast coast of the United States into the western North Atlantic). The implications for the resulting sensible weather and predictability of the flow are discussed. An adjoint-derived sensitivity study was conducted for one of the KP1 cases identified in the climatology. The results provide dynamical confirmation of the LSC precursor identification for the events. The upper-tropospheric precursor is seen to play a key role not only in the onset of the lower-tropospheric height falls and concomitant circulation increases, but also in the eastward extension of the polar jet across the Pacific. The evolution of the forecast sensitivities suggest that LSC events are not a manifestation of a modal instability of the time mean flow, but rather the growth of a favorably configured perturbation on the flow.


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