Patterns on freeze-fractured plasma membranes of Lily pollen tubes

The cell wall of Lilium pollen tubes contains less skeletal cellulose (Herth et al. 1974) than the pollen tube wall of Petunia (Sassen 1964, Engels 1974) and Nicotiana (Kroh & Knuiman 1982). A crystalline modification of polymeric /?-1,3-glucan predominates in the lily pollen tube wall (Herth et al. 1974). Since microfibril synthesis presumably is a membrane-bound process (Brown 1985), we studied plasma membranes of lily pollen tubes with the freeze-fracture procedure for comparison with plasma membranes of tobacco pollen tubes (Kroh& Knuiman 1985).