01661nab a2200253 a 4500 AR-ReUNN 20260702003309.0 260630s2006 ag |||||||||||||||||eng eng Yuhl, D. e. 154524 Majumdar, S. K. 154505 Light and electron microscope studies of Haworthia (Liliaceae) pollen / D. E. Yuhl; S. K. Majumdar 2006 7 páginas fot. byn. Pollen from 14 species of Haworthia (Family Liliaceae, Tribe Aloineae) were examined with the electron (scaning and transmission) and light microscopes. Optical microscope studies revealed a pollen size that depends upon the chromosome number; pollen grains of the diploid species are smaller than those from polyploid plants. Pollen grains are monoaperturate and, under the SEM, all 14 species display a perforated tectum. However, the proximal exine surface is smooth in some species and rough in others. The SEM study showed an identical tripartite ektexine composed of the foot layer, columellae and tectum in all species. The intine beneath the foot layer, however, exhibits certain variations in thickness. No differences in pollen fine structure of diploid and euploid plants could be detected. The need for further studies on the pollen ultrastructure was emphasized. Polen 6254 Haworthia 154525 Liliaceae 115697 Phyton : Revista Internacional de Botánica Experimental = International Journal of Experimental Botany 0031-9457 v. 41 n. 1-2 (1981) 238927 ART (IBONE)34618 239018 239018 239018 AR-ReUNN spa AR-ReUNN aacr2