Structure of the seed coat of the species of Asteraceae. II (tribe Heliantheae)

We present the study of structure seed coat 52 species from 31 genera (Acmella, Ambrosia, Aspilia, Balsamorhiza, Blainvillea, Borrichia, Chrysogonum, Clibadium, Delilia, Echinacea, Eclipta, Engelmannia, Helianthella, Helianthus, Heliomeris, Heliopsis, Iva, Lindheimera, Parthenium, Ratibida, Rudbeckia, Sanvitalia, Silphium, Sphagneticola, Synedrella, Synedrellopsis, Tithonia, Verbesina, Xanthium, Zaluzania, Zinnia) ten subtribes tribe Heliantheae Asteraceae family. The was carried out by scanning electron microscopy. It has been established that have a distinctly sculptured or smooth, well-developed testa, which remains until full maturity achenes. sculpture surface in most is determined exotesta cells. several types and subtypes cells due to degree type thickening cell walls were revealed. seeds make up diverse. shape specifications within genus subtribe are diverse, as result, it not possible identify characters inherent entire tribe, well its genera. division into supported results our study. conservative nature testa allows use them solving problems taxonomy genera, phylogenetics, establish homogeneity taxa united tribe.