Multiple developmental processes underlie sex differentiation in angiosperms

Gynoecium diversity and systematics in basal monocots

Morphology, species delimitation, and interspecific relationships were evaluated in a phylogenetic context in the aquatic monocotyledon genus Vallisneria using a combination of morphological and molecular (nrITS, rbcL, trnK 5′ intron) data. Contrary to previous studies that recognized few species worldwide, we distinguished 12 species by molecular data, and an additional 2–3 species by morphological differences within groups that were invariant at the molecular level. Two new Vallisneria species ( V. australis , V. erecta ) are formally described. Other potentially novel species were detected from the cultivated material examined but require further study to elucidate their taxonomic status. Phylogenetic analyses indicated that vittate (caulescent) species (including Maidenia rubra) are not basal, but nested between two groups of rosulate (rosette) species. To preserve Vallisneria as monophyletic, a new combination is made ( V. rubra ) that accommodates the transfer of M. rubra to Vallisneria. Se...

https://www.jstor.org/stable/info/25064317

Systematics of Vallisneria (Hydrocharitaceae)

The family Hydrocharitaceae, with 15 genera and ca. 80 species, shows a remarkable morphological diversity which presumably developed as an adaptation to their aquatic habitat. This is particularly true in the case of the many different kinds of pollination mechanisms. To gather more basic information regarding the adaptive evolution of Hydrocharitaceae, we have carried out a phylogenetic analysis based on the sequences of therbcL andmatK. Our resulting neighbor-joining distance tree provides the following insights: (1) none of the previous classification systems were supported by molecular phylogenetic tree; (2) Najas (Najadaceae), which has never been included in Hydrocharitaceae except in Shaffer-Fehre's (1991) system based on seed coat structures, is an ingroup of Hydrocharitaceae; (3) Limnocharitaceae and Alismataceae are sister groups of Hydrocharitaceae; (4) the three marine genera,Halophila, Enhalus andThalassia, are monophyletic; and (5) a peculiar pollination mechanism specific to Hydrocharitaceae (Hydrocharitaceae-epihydrophily), underwent a parallel evolution.

Phylogeny of the family Hydrocharitaceae inferred from rbcL and matK gene sequence data

The pollination ecology of Zannichellia palustris L. (Zannichelliaceae).

Floral development of Maidenia rubra was followed from initiation to maturity. Plants are dioecious. Both male and female inflorescences develop from complexes initiated subapically. Complexes have three meristematic components that include two inflorescence initials flanking a central primordium; these form sequentially in the axil of the preceding initial. The third component also produces an inflorescence and branches sympodially to form further floral initials that have a spiral arrangement. The female inflorescences produce a single flower only with an inferior, unilocular ovary and three sepals, staminodes and bifid stigma. In the locule, numerous bitegmic ovules, borne panetally, are produced. A male inflorescence produces hundreds of small flowers that are released and float to the surface individually. Each male flower has three sepals, a staminode and two stamens, each anther consisting of three locules with eight pollen grains. Prior to maturation, the anther wall breaks down leaving a membraneous layer that assists in binding the octad of pollen grains together. Both male and female inflorescences are enclosed in a pair of fused bracts. The floral morphology is compared with other closely related genera in the Hydrocharitaceae and the unique features are assessed.

Floral development of Maidenia rubra Rendle, (Hydrocharitaceae)

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

CA McConchie

Author Tools

Chat about Author

Papers

Floral development of Maidenia rubra Rendle, (Hydrocharitaceae)