On the inner cuticle of angiospermous seeds

摘要

The inner cuticle of seeds has been studied for 50 plant species belonging to different angiospermous genera and families by means of transmission electron microscopy (TEM). In 48 species, the cuticle is found between the testa and the endosperm. Published sources do not elucidate the origin of this cuticle. In the studied species, the cuticle is mostly present only on the surface of the endosperm or the nucellus cells. In some genera, the cuticle is present on the inner testa cells (species of Festuca and Artemisia), or only on these cells (Arabidopsis). Our study has shown the cuticle to have different thickness (from 0.11 to 6.61 #mu#) and structure (7 structure types). It is found that, in the species with crassinucellate ovule and no perisperm,the cuticle is located on remains of the nucellus (e.g. Alcea, Urtica and Festuca), and, in the species with tenuinucellate ovule, it is located on the endosperm cell walls (29 species). In plants of the same species grown under different conditions, thecuticle thickness may either remain constant (Artemisia commutata), or vary significantly (Festuca pratensis).