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Related to apospory: apogamy


 (ăp′ə-spôr′ē, ə-pŏs′pə-rē)
The development of a gametophyte directly from a sporophyte without the occurrence of meiosis or spore formation.

a·pos′por·ous (ə-pŏs′pər-əs), ap′o·spor′ic (-spôr′ĭk) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


1. (Botany) botany development of the gametophyte from the sporophyte without the formation of spores
2. (Botany) the development of an embryo of a flowering plant outside the embryo sac, from a cell of the nucellus or chalaza
[C19: from apo- + spore + -y1]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈæp əˌspɔr i, -ˌspoʊr i, əˈpɒs pə ri)

the development of a gametophyte from a sporophyte without meiosis.
ap`o•spor′ic (-ˈspɔr ɪk, -ˈspɒr-) a•pos′por•ous, adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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References in periodicals archive ?
von Aderkas, "Enhancement of apospory in liquid culture of Matteuccia struthioptens," Annals of Botany, vol.
Since the latter were clearly homologous to each other, this meant that the moss seta (asexual generation) was homologous to the moss stem (sexual generation), as confirmed by observations of the vegetative sprouting of the seta (apospory).
Forty-nine plants (64.4%) formed some aposporous embryo sacs in addition to the normal meiotic sac, and the remaining 27 plants were free of apospory. Plant Q4205 was selected from among these 27 sexual plants.
Apogamy ("without gametes") and apospory ("without spores") are, to an extent, misnomers, because in some instances gametes and spores are still produced in the life cycle when these phenomena occur; the chromosome complement of the apogamously tbrmed sporophyte and aposporously produced gametophyte is, however, sometimes other than the usual for these generations (for example, both gametophyte and sporophyte in the life cycle may be found to be diploid).
The grass reproduces primarily by apomixis with the mechanism being apospory followed by pseudogamy (Fisher et al., 1954; Snyder et al., 1955).
Apomixis (i.e., asexual reproduction by seeds) is a common trait in the genus, being apospory (in which a non reduced megagametophyte originates from a somatic cell, usually a nucellar cell) the most frequent type, and diplospory (in which a non reduced megaspore originates from the reproductive cell itself, with the later failing to successfully complete meiosis) only of occasional occurrence (Quarin, 1992).
The grass reproduces primarily by apomixis, with the mechanism being apospory followed by pseudogamy (Fisher et al., 1954; Snyder et al., 1955).
Gametophytic apomixis (asexual reproduction through seed) involves the formation of unreduced embryo sacs from the MMC (diplospory) or from nucellar cells (apospory).
Crosses of sexual with aposporous genotypes of buffelgrass yielded segregation ratios compatible with an inheritance model that postulates expression of apospory requires the dominant allele (A) of a single autotetrasomically inherited locus, assuming random assortment of chromatids (Sherwood et al., 1994).