THE ROLE OF THE INTINE AND CYTOPLASM IN THE ACTIVATION AND GERMINATION PROCESSES OF POACEAE POLLEN GRAINS

Ultrastructural modifications of the intine and cytoplasm, during the maturation, activation and germination processes are described for sev eral Poaceae pollen grains. Allergenic and antigenic proteins were fou nd in the non apertural inline during the limes of activation and germ ination, using TEM immunolabelling. This fact may be related to the fu nction of the non apertural inline during the processes of pollen acti vation and pollen tube formation prior to fecundation. Changes in the granular particles of the cytoplasm are described and their role in po llen wall development is suggested. The pectic-cellulosic and callosic lavers of the pollen tube were formed on the degraded intine, and a r elationship between pollen tube wall development and the substances ex pelled from the fibrillar particles was observed. The immunolabelling of the starch granules may be in agreement with their role in the alle rgenic process.