Seed formation in two species ofAdesmia(Fabaceae): co-occurrence of micropylar and lateral endosperm haustoria in legumes and its taxonomic value

Abstract

Seed ontogeny of Adesmia bicolor and Adesmia latifolia was analysed using light microscopy and standard histological techniques. Fertilization was porogamic. Linear proembryonal tetrads were observed in A. bicolor. The robust elongated suspensors possessed specialized basal cells. The nucellar epidermis became endothelial. The free-nuclear endosperm produced a micropylar, filamentous and ephemeral haustorium and a lateral sac-like haustorium at the funicular side. The cellular endosperm was initiated from the micropylar zone after the cordiform embryo stage. It mostly disintegrated in mature seeds. The sclerified bilayered testa was derived from the outer ovular integument. Different astrosclereid arrangements beyond the lens in both Adesmia species may be related to the different habitats of the two species. The occurrence of both micropylar and lateral nuclear endosperm haustoria has so far not been reported in Fabaceae and is the most distinctive embryological character of Adesmieae. The taxonomic value of the mostly uniform morphology of the suspensor in the Adesmia species studied could also be relevant. The nature of seed endothelia in many Fabaceae requires accurate redetermination prior to taxonomic use.

Estudos morfo-anatômicos relacionados à dormência em sementes de Adesmia tristis Vogel (Fabaceae)

“…Em corte transversal, notou-se que todos os traqueóides apresentaram um arranjo vertical (Figura 1E). Esse padrão foi registrado nas outras espécies de Adesmia (A. securigerifolia, A. bicolor e A. latifolia) estudadas quanto a esse aspecto (Izaguirre et al, 1994;Rodriguez-Pontes, 2008) e é considerado o mais comum registrado entre as Faboideae (Lersten, 1982). Segundo Rodriguez-Pontes (2008), estes traqueóides, em A. latifolia, apresentam ornamentação de parede do tipo escalariforme, porém com contornos mais achatados e, em A. bicolor, são do tipo reticulado.…”

Embryology ofOnobrychis persicaSirj. and Rech.f. (Fabaceae) and its systematic implications

“…Embryological studies in Papilionoideae (Ashrafunnisa and Pullalah 1999;Riahi et al 2003;Faigo´n-Soverna et al 2003;Moço and Mariath 2003;Zulkarnain 2005;Galati et al 2006;Rezanejad 2007;Rodriguez-Pontes 2008;Riahi and Zarre 2009;Salinas-Gamboa et al 2016) and a few embryological studies in Onobrychis (Chehregani et al 2011;Ghassempour and Majd 2012) have provided useful characters in embryogenesis and classification. Therefore, in this study we investigate detailed embryological processes in O. persica using bright field, polarizing and fluorescence microscopy and compare them with some spices in this genus.…”

Allometric relationships between diaspore morphology and diaspore covering anatomy of herbaceous species from central-eastern Europe

“…Baskin et al, 2000;Fenner, 2000;Baskin and Baskin, 2001;Rodriguez-Pontes, 2008;Graeber et al, 2011;Morris et al, 2011). Therefore, there is a wide range of literature examining their evolution, ecology, physiology and anatomy (e.g.…”

“…It seems obvious that closely related taxa have a more similar histo-anatomical diaspore structure than very distant relatives. In the Fabaceae, the diaspores are seeds with thick seed coats consisting of palisade sclerenchyma, brachysclereids and some live nutritious tissues (Tămaș, 2004;Rodriguez-Pontes, 2008). In the Fabaceae, the diaspores are seeds with thick seed coats consisting of palisade sclerenchyma, brachysclereids and some live nutritious tissues (Tămaș, 2004;Rodriguez-Pontes, 2008).…”