GENERATIVE CELL ENVELOPE IN POLLEN GRAINS AS A SECRETION SYSTEM, A POSTULATE

This paper describes the changes undergone by the layer dividing the vegetative from the generative cell. The abundant contents of the space inside the membrane, consisting of opaque bodies, vary considerably as the pollen grain matures, and decrease in volume pari passu with the formation of the dense bodies in the plasm of the vegetative cells. The dense bodies constitute a layer of droplets surrounding the enveloping membrane of the generative cell within the cytoplasm of the vegetative cell. Connexions have been observed between the dense bodies and the partition layer which seem to indicate that the latter is apparently responsible for their organization, and is the area in which the synthesis of their contents takes place as well. The deposition of the dense bodies on the plasmalemma of the pollen grain points to their participation in the formation of one or other of the layers in which the grain is enveloped. © 1969 Springer-Verlag.