AN ELECTRON MICROSCOPE STUDY OF GERMINATING LYCHNIS ALBA POLLEN

Abstract

The fine structure of germinating Lychnis alba pollen is described and correlated with some basic tests for chemical composition. The primary storage product in both pollen grain and pollen tube appears to be lipid. Pregermination synthesis of pollen tube wall material appears characteristic in this species, along with the presence of crystalloid structures having approximately 80 A periods. The crystalloid bodies are not found in the tip cytoplasm of the pollen tubes. Limited acid phosphatase activity is found associated with the crystalloid structures as well as within vesiculate structures of the pollen grain. The cytoplasmic structure of both the pollen grains and pollen tubes is characterized by few dictyosomes and plastids and no microtubules, although mitochondria and polyribosomes are abundant. Pectins have not been verified in the pollen tube walls, their primary composition being cellulose.