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1.
Trends Plant Sci ; 25(12): 1173-1176, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046371

RESUMO

Biologists unable to recognize common plants, and a decline in botany students, faculty, courses, university departments, and herbaria, highlight the current erosion of botany. How did we reach this crisis, knowing that plants form the basis for life? What are the causes? What can we do to reverse it?


Assuntos
Botânica , Plantas
2.
PhytoKeys ; 145: 57-62, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32327926

RESUMO

A new subspecies and two new combinations are proposed in Onagraceae. Ludwigia glandulosa Walter subsp. brachycarpa C.-I Peng, subsp. nov. is morphologically distinct from the typical subspecies, with smaller capsules and leaves, different seed coat, and a restricted distribution. Epilobium sect. Pachydium (Fischer & C. A. Meyer) Hoch & K. Gandhi, comb. nov. refers to a distinctive group of species formerly known as Boisduvalia Spach and as Epilobium sect. Boisduvalia (Spach) Hoch & P. H. Raven. And Chamaenerion speciosum (Decaisne) Hoch & K. Gandhi, comb. nov. is proposed for a distinctive Himalayan species originally described in Epilobium.

3.
Am J Bot ; 105(5): 875-887, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29791715

RESUMO

PREMISE OF THE STUDY: Interpreting relationships within groups containing polyploids, which are frequent in angiosperms, can be greatly assisted by genomic techniques. In this study, we used a genome-skimming approach to investigate the evolutionary relationships and origins of polyploids in the monophyletic group, Ludwigia section Macrocarpon (Onagraceae), which includes diploid, tetraploid, and hexaploid taxa. METHODS: We sampled all known taxa and ploidy levels in the section and conducted shotgun sequencing. We assembled plastomes, mitochondrial sequences, and completed nuclear ribosomal regions, reconstructed phylogenies, and conducted comparative genomic analyses for plastomes to gain insights into the relationships among studied taxa. KEY RESULTS: Within the section, results showed that the South American diploid taxa L. bonariensis and L. lagunae were closely related. We reported the first chromosome count (2n = 4× = 32) for L. neograndiflora, which is closely related to the two South American diploid taxa, although its exact origin remains unclear. The samples of the widespread, polyploid taxon L. octovalvis do not form a monophyletic group. Both tetraploid and hexaploid L. octovalvis lineages have originated more than once. At least one tetraploid in the L. octovalvis lineage may have been involved in the origins of hexaploids. One or more extinct/unsampled intermediate tetraploids in the L. octovalvis lineages had also likely been involved in the origins of hexaploids. CONCLUSIONS: Genome skimming provided important insights into the complex evolutionary relationships within sect. Macrocarpon, but additional sampling and data from single-copy nuclear regions are necessary to further elucidate the origins of the polyploids in this section.


Assuntos
Evolução Molecular , Genoma de Planta , Onagraceae/genética , Filogenia , Poliploidia , Análise de Sequência de DNA
5.
Genome Announc ; 4(6)2016 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-27856583

RESUMO

Here, we present the first plastome of Ludwigia octovalvis (Onagraceae, Myrtales) as well as the first plastome in the subfamily Ludwigioideae. This genome is notable for its contracted inverted repeat regions and an expanded small single-copy region compared to other species in the orders Myrtales and Geraniales.

6.
PhytoKeys ; (50): 25-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26140017

RESUMO

In 2007, Wagner and Hoch proposed the new name Oenotheraxenogaura W.L.Wagner & Hoch for the species then known as Gauradrummondii (Spach) Torrey & A. Gray (non Oenotheradrummondii Hooker, 1834). However, the authors overlooked the availability of Gaurahispida Bentham (1840) for this species. Accordingly, we herewith make the appropriate new combination for this species, Oenotherahispida (Bentham) W.L.Wagner, Hoch & Zarucchi, and place Oenotheraxenogaura in synonymy.

7.
PhytoKeys ; (50): 31-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26140018

RESUMO

In 1953, Hara provided new combinations for many sectional and species names when he combined Jussiaea L. with Ludwigia L., and at the time, Ludwigiasect.Oligospermum (Micheli) H.Hara was the correct name for one well-defined section. However, subsequent changes to/clarifications of the botanical code have necessitated a change for that name in that now an autonym is treated as having priority over the name or names of the same date and rank that established it. Since Hara's combination was based on Jussiaeasect.Oligospermum Micheli, the correct name for this section is Ludwigiasect.Jussiaea (L.) Hoch, W.L.Wagner, & P.H.Raven.

8.
PhytoKeys ; (28): 61-72, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24399892

RESUMO

The long-recognized genus Gaura was shown recently to be deeply nested within one of two major clades of Oenothera. New molecular data indicate further taxonomic changes are necessary in Oenothera sect. Gaura. We make these changes here, including three new combinations, in advance of the Onagraceae treatment for the Flora of North America. The new phylogenetic studies show that several pairs of taxa treated as subspecies in the most recent revision by Raven and Gregory (1972) had independent origins within sect. Gaura, and are here elevated to species level (Oenothera nealleyi for Gaura suffulta subsp. nealleyi; Oenothera dodgeniana for Gaura neomexicana subsp. neomexicana; and Oenothera podocarpa for Gaura hexandra subsp. gracilis). Also, a nomenclatural problem in Oenothera sect. Calylophus is corrected by adopting the name Oenothera capillifolia Scheele for the species known previously, and nomenclaturally correct, as Calylophus berlandieri Spach. This problem necessitates a new combination Oenothera capillifolia subsp. berlandieri.

9.
PhytoKeys ; (5): 1-3, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22171188

RESUMO

The Nomenclature Section held just before the 18th International Botanical Congress in Melbourne, Australia in July 2011 saw sweeping changes to the way scientists name new plants, algae, and fungi. The changes begin on the cover: the title was broadened to make explicit that the Code applies not only to plants, but also to algae and fungi. The new title will now be the International Code of Nomenclature of algae, fungi, and plants. For the first time in history the Code will allow for the electronic publication of names of new taxa. In an effort to make the publication of new names more accurate and efficient, the requirement for a Latin validating diagnosis or description was changed to allow either English or Latin for these essential components of the publication of a new name. Both of these latter changes will take effect on 1 January 2012. The nomenclatural rules for fungi will see several important changes, the most important of which is probably the adoption of the principle of "one fungus, one name." Paleobotanists will also see changes with the elimination of the concept of "morphotaxa" from the Code.

10.
Am J Bot ; 90(1): 107-15, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21659085

RESUMO

Despite intensive morphological and molecular studies of Onagraceae, relationships within the family are not fully understood. One drawback of previous analyses is limited sampling within the large tribe Onagreae. In addition, the monophyly of two species-rich genera in Onagreae, Camissonia and Oenothera, has never been adequately tested. To understand relationships within Onagraceae, test the monophyly of these two genera, and ascertain the affinities of the newly discovered genus Megacorax, we conducted parsimony and maximum likelihood analyses with rbcL and ndhF sequence data for 24 taxa representing all 17 Onagraceae genera and two outgroup Lythraceae. Results strongly support a monophyletic Onagraceae, with Ludwigia as the basal lineage and a sister-taxon relationship between Megacorax and Lopezia. Gongylocarpus is supported as sister to Epilobieae plus the rest of Onagreae, although relationships within the latter clade have limited resolution. Thus, we advocate placement of Gongylocarpus in a monogeneric tribe, Gongylocarpeae. Most relationships within Onagreae are weakly resolved, suggesting a rapid diversification of this group in western North America. Neither Camissonia nor Oenothera appears to be monophyletic; however, increased taxon sampling is needed to clarify those relationships. Morphological characters generally agree with the molecular data, providing further support for relationships.

11.
Cladistics ; 6(2): 171-182, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34933511

RESUMO

Abstract- Circaea (Onagraceae), a genus of seven species from the northern hemisphere, forms a monophylctic group defined by the following synapomorphies: two stamens (opposite the sepals), fruits indehiscent capsules, hooked hairs on the fruits, and perianth parts reduced to two. A cladistic analysis of the genus was performed using 22 characters from morphology, anatomy and palynology. The seven species and seven additional subspecies were considered the terminal taxa. Polarity of the characters is based on the outgroup comparison method. Eighteen equally parsimonious cladograms were produced, each with 32 steps and a consistency index of 0.75. A successive weighting procedure was applied, resulting in six cladograms with a consistency index of 0.95. All 24 cladograms share the following seven monophylctic groups: (1) all species except C. cordala and C. glabrescens (stipules deciduous); (2) the group of C. mollis, the three subspecies of C. lutetiana and C. erubescens (exsertcd nectary); (3) C. repens and all six subspecies of C. alpina (single-seeded fruits, stolons terminated by tubers, and viscin threads reduced or absent); (4) the six subspecies of C. alpina (unilocular ovaries with no trace of a second loculc and tardily opening perianth); (5) C. alpina subspecies alpina, micrantha, pacifica, and imaicola (flowers opening on ascending to erect pedicels); (6) C. alpina subspecies alpina, micrantha, and pacifica (translucent leaves); (7) C. alpina subspecies alpina and murantha (glabrous stems). Results of the cladistic analysis support most of the current systematic classification of the genus, except for the relationships among the three subspecies of C. lutetiana.

12.
Oecologia ; 14(4): 353-374, 1974 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28308659

RESUMO

Nectar foraging preferences of Colias butterflies in two different mountain ecosystems are examined with respect to plant distribution, nectar quantity, carbohydrate (and amino acid) content of nectar, and visual pattern of the plants utilized and avoided. Colias, and apparently numerous other small, ectothermic, low-energy-demand pollinators, "patronize" plants producing relatively dilute nectars containing a high proportion of monosaccharide sugars and significant amounts of polar, nitrogen-rich amino acids. These plants also converge on a common "target" flower pattern in ultraviolet and human-visible light. High-energy demand, endothermic pollinators, by contrast, appear to require higher concentration nectars and/or higher proportions of di- and oligosaccharide sugars. These results are discussed in the light of water balance and energy budget demands of different pollinator classes. Questions are also raised concerning behavioral aspects of pollinator search for resources and the pertinence of these data to the concept of floral mimicry.

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