Aline Redondo Martins
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Sandra Maria Carmello-Guerreiro
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Marcos Silveira Buckeridge
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Clovis Oliveira Silva
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Beatriz Appezzato-da-Glória
Smilax polyantha Grisebach is a species native to the Brazilian Cerrado biome and is known as sarsaparilla in folk medicine. Despite its popular use, little is known about the propagation of this species, which is still actively illegally exploited. The present study aims to analyse the seed ontogeny and perform endosperm chemical analyses in S. polyantha to elucidate the structural and chemical factors that could be associated with the low germination rates and structural organisation of the seed. The ovules are orthotropic and bitegmic, have short funicles, single collateral vascular bundles that end in the chalaza, and a hypostasis that is composed of chalazal and nucellar cells. The seed covering is non-multiplicative. In mature seeds, the cellularised endosperm has thick-walled cells, the embryo is small and the tegmen comprises two layers of periclinal elongated cells with a red–orange content, which are covered by a cuticle. Histochemical tests detected the presence of lipids, proteins and polysaccharides in the cellular content of mature seeds. Chemical analyses indicated 46.7% hemicellulose per total weight, 67.3% glucose, 30.7% mannose, 1.9% galactose and an absence of fucose, arabinose and rhamnose. In conclusion, the delayed seed germination in S. polyantha is associated with the seed endosperm cell walls.
Arabinoxylan, β‐glucan and pectin in barley and malt endosperm cell walls: a microstructure study using CLSM and cryo‐SEM