TY  - SER
AU  - Majumdar,S.K.
AU  - Lowry,R.J.
TI  - An electron microscope study of the barrier between vegetative and generative nuclei in the pollen of Gasteria armstrongii / S. K. Majumdar; R. J. Lowry
PY  - 2006///
KW  - Gasteria
KW  - Liliaceae
KW  - Polen
N1  - fot. byn
N2  - Ultrastructure studies of the pollen grains of Gasteria armstrongii revealed the existence of a barrier between the vegetative and generative nuclei. The layer is continuous with the intine of the pollen wall. It is suggested that the cisternae of the endoplasmic reticulum appear between the two nuclei and deposition of pectic substances occurs in them. Later the pectine containing cisternae line up in the equatorial region and fuse to from the layer. Finally the layer separates from the intine and becomes the envelope around the generative nucleus. The chemical nature of the barrier is discussed
ER  -