The investigations in Pteridophytes probably of most interest and importance ing of apogamy and apospory, it is important to define these terms at the outset. Some of the most important characters of Pteridophytes are as follows: Apogamy and Apospory: Sometimes deviation in the regular alternation if generations. Apogamy, apospory and parthenogenesis in the Pteridophytes II Steil, W.N.. Bot Rev: This is a supplement to the review which appeared in Bot.
|Published (Last):||2 April 2010|
|PDF File Size:||4.65 Mb|
|ePub File Size:||5.16 Mb|
|Price:||Free* [*Free Regsitration Required]|
All Pteridophytes are annual and herbaceous, e. Most users should sign in with their email address.
13 Important Characters of Pteridophytes – Explained!
Apogamy was induced in the fern Ampelopteris prolifera by culturing the gametophytes on mineral nutrients supplemented with various concentrations of sucrose. Embryologie und Fortpflanzungsbiologie der Angiospermen: Natural apogamy is common in ferns like Dryopteris, Adiantum, Osmunda, Pteris etc. Retrieved from ” https: Anybody can ask a question Anybody can answer The best answers are voted up and rise to the top.
It furthers the University’s objective of excellence in research, scholarship, and education by publishing worldwide. The culture of bryophytes including apogamy apospory parthenogenesis and protoplasts. As Jens Clausen put it : Botanical Journal of the Linnean Society 62 4: The central cell of the megagametophyte may require fertilization to form the endospermpseudogamous gametophytic apomixisor in autonomous gametophytic apomixis fertilization is not required.
Apomictically produced offspring are genetically identical to the parent plant. Examples of apomixis can be found in the genera Crataegus hawthornsAmelanchier shadbushSorbus rowans and whitebeamsRubus brambles or blackberriesPoa meadow grassesNardus stricta MatgrassHieracium hawkweeds and Taraxacum dandelions.
For English speakers, Maheshwari  is very influential. Leaves with petiole, excised from aseptically raised plants from excised cultured buds, also exhibited apospory, while no success was achieved with the excised leaves of the parent plantS. Cytology of apogamy and apospory in Osmunda javanica Bl.
Apospory | botany |
Email alerts New issue alert. See also androgenesis and androclinesis described below, a type of male apomixis pteridophytess occurs in a conifer, Cupressus dupreziana. Dryopteris or heterosporous e.
You could not be signed in. The University of Chicago press. Close mobile search navigation Article navigation. Not to be confused with automixis or autogamy. Illuminating the systematics of the Spiranthes sinensis species complex Orchidaceae: Apospory and apogamy in a species of Tectaria.
Pteris, Nephrolepis, Drynaria etc. The leaves bearing sporangia are called sporophylls. For androgenetic alopecia, see Pattern hair loss. Azolla, Selaginella but a few are perennial woody tree fern e. The differentiation of this gametophytic callus was conditioned by sucrose and auxin concentrations of the medium.
Apogamy, apospory and parthenogenesis in the Pteridophytes II. Parthenogenesis apogamy and apospory in alaria crassifolia laminariales.
Buy PDF – Apogamy, apospory and parthenogenesis in the Pteridophytes II
In some cases sporophylls for compact structures called cones or strobili e. Citing articles via Google Scholar. Developmental evidence helps resolve the evolutionary origins of anther appendages in Globba Zingiberaceae. The sporophyte produces meiosopres inside sporangia. Surrogate mother for endangered Cupressus “. Thus “normal asexual reproduction ” of plants, such as propagation from cuttings or leaves, has never been considered pteridophyhes be apomixis, but replacement of the seed by a plantlet or replacement of the flower by bulbils were categorized as types of apomixis.
The evolutionary biology of plants. In gametophytic apomixisthe embryo arises from an unfertilized egg cell i.
Apogamy, apospory and parthenogenesis in the Pteridophytes II
Structure and Reproduction Replication Cycle. Wikipedia articles with GND identifiers. Apospory was induced on the sexual cotyledonary and juvenile sporeling leaveS. You do not currently have access to this article. Phloem consists of sieve cells only. Selaginella, Equisetum, Ophioglossiim etc.
Agamospermy occurs mainly in two forms: