Anatomía reproductiva en flores estaminadas y pistiladas de Allophylus edulis (Sapindaceae)

Abstract

Se estudió la esporogénesis y gametogénesis de flores estaminadas y pistiladas de Allophylus edulis (Sapindaceae). La anteras jóvenes son similares en ambos tipos de flores, comparten el tipo básico de desarrollo anteral; presentan epidermis, endotecio con células binucleadas, dos capas medias, y tapete de tipo secretor, con células binucleadas. La microsporogénesis es normal, la división de las células madres de las micrósporas es simultánea y las tétrades son tetraédricas y decusadas. La antera madura en flores estaminadas presenta células epidérmicas adelgazadas a nivel del estomio y el endotecio con engrosamientos fibrosos. Se aprecia un único lóculo por teca por disolución del septo y los granos de polen son liberados al estado 2-celular, éstos son triporados o tetraporados. El gineceo está reducido a un pistilodio tricarpelar, trilocular, con un óvulo por lóculo. El óvulo degenera antes de que ocurra la meiosis. La antera madura de las flores pistiladas difiere anatómicamente de la de las flores estaminadas. El endotecio no desarrolla engrosamientos fibrosos, las capas medias y el tapete persisten, y el estomio no es funcional; las anteras son indehiscentes. El gineceo de las flores pistiladas, presentan ovario tricarpelar y trilocular. Cada lóculo contiene un óvulo hemianátropo, bitegumentado y crasinucelado, con obturador desarrollado; el megagametófito es de tipo Polygonum. Se discuten los resultados obtenidos en relación a lo conocido para la familia.

Anther and gynoecium structure and development of male and female gametophytes of Koelreuteria elegans subsp. formosana (Sapindaceae): Phylogenetic implications

“…formosana, the tapetum is secretory. This tapetum type is unique in the family and possibly in Sapindales, whereas the number of nuclei in tapetal cells is a very variable character (Gulati and Mathur, 1977;Mathur and Gulati, 1980, 1981, 1989Ha et al, 1988;Cao et al, 2008;Solís et al, 2010;Zhou and Liu, 2012;Zini et al, 2012;González et al, 2014González et al, , 2017. The tapetal cells in K. elegans subsp.…”

“…The micropyle can be endostomic (Dodonaea Mill., Delavaya Franch., Cardiospermum, Paullinia, Serjania, Urvillea, Allophylus L., and Magonia A. St. Hil., Karkare-Khushalani and Mulay, 1964;Weckerle and Rutishauser, 2005;Cao et al, 2014;González et al, 2014González et al, , 2017 or amphistomic (Filicium Thwaites, Gulati and Mathur, 1977). However, an amphistomic micropyle of zigzag shape, as was observed here, has also been reported in Averrhoidium and within many other lineages of the Sapindales (Weckerle and Rutishauser, 2003;reviewed in Endress and Matthews, 2006;Bachelier and Endress, 2009;Bachelier et al, 2011).…”

“…Finally, the female gametophyte of Polygonum type with presence of ephemeral antipodals can be considered a predominant feature of the Sapindales (Nair and Joseph, 1960;Gulati and Mathur, 1977;Mathur and Gulati, 1980, 1981, 1989Ha et al, 1988;Johri et al, 1992;Ye et al, 1992;Cao et al, 2008;Zhou and Liu, 2012;González et al, 2014González et al, , 2017. However, the Penaea-type female gametophyte is restricted to Biebersteiniaceae, which is sister to all other Sapindales (Yamamoto et al, 2014).…”

“…Similar developmental pattern has been reported for other imperfect flower of Sapindaceae. (Nair and Joseph, 1960;Mathur and Gulati, 1980, 1981, 1989Ha et al, 1988;Van der Ham, 1990;Ferrucci, 1991;Cao et al, 2008;Solís et al, 2010;Acevedo-Rodríguez et al, 2011;Vary et al, 2011;Zhou and Liu, 2012;Zini et al, 2012;González et al, 2014González et al, , 2017 as well as in Aceraceae (Jacobs and Lersten, 1994;Hu et al, 2009;Yadav et al, 2016), Meliaceae (Styles, 1972;Gouvêa et al, 2008a), several representatives of Anacardiaceae and Burseraceae (Wannan and Quin, 1991;Bachelier and Endress, 2009), and Kirkiaceae (Bachelier and Endress, 2008).…”

“…Thus, the presence of staminate flowers with rudimentary gynoecium and perfect flowers that are functionally pistillate (because they have nonfunctional stamens) is common. Despite the fact that Sapindaceae is diverse in terms of species number, the studies on the floral morpho-anatomy and/or embryology were limited to only a few species (Nair and Joseph, 1960;Khuslani, 1963;Karkare-Khushalani and Mulay, 1964;Gulati and Mathur, 1977;Mathur and Gulati, 1980, 1981, 1989Ha et al, 1988;Ronse Decraene et al, 2000;Weckerle and Rutishauser, 2005;Cao et al, 2008;Solís et al, 2010;Zhou and Liu, 2012;Zini et al, 2012;González et al, 2014González et al, , 2017Avalos et al, 2017;Cao et al, 2018), and most of the information derived from these studies have not been included in morphological characterizations of groupings supported by the molecular phylogeny.…”