Lignin and Dormancy in Seeds of Three Legumes Species of Atlantic Forest

The relationship between the presence of lignin and seed dormancy was evaluated in three legume tree species occurring in the Atlantic forest. The species studied were: Cassia grandis L.f., Anadenanthera macrocarpa (Benth.) Brenan and Enterolobium contortisiliquum (Vell.) Morong. The anatomical procedures indicated the presence of lignin in the palisade cells of the exotesta, in the osteosclereids and in the parenchymatic cells of the mesotesta. The high values of lignin content corresponded to the low rate of dormancy. Although lignin is a hydrophobic substance its presence in the integument of the seeds allows a higher flux of liquids directly related to the occurrence of lignin.

Keywords:
seed; lignin; dormancy.