Annals of Botany 71: 97-105, 1993
© 1993 Annals of Botany Company
Pollen Wall Ontogeny of Felicia muricata (Asteraceae: Astereae)
Department of Plant and Soil Sciences, Potchefstroom University for Christian Higher Education, Potchefstroom, 2520 Republic of South Africa
Pollen wall development in Felicia muricata Thunb. Nees (Asteraceae) was investigated by electron microscopy after addition of the lypophilic dye malachite green to the primary fixative. Pollen wall formation commences with the deposition of fibrillar electron dense units which represent future interbacular spaces. Radially arranged trilammelate structures develop between the fibrillar units. Sporopollenin is deposited in the trilammelate structures. After release of the microspores from the tetrad, formation of interbacular spaces is accompanied by disintegration of fibrillar units. Endexine formation occurs on white lines of unit membrane dimensions. Intine formation follows the pattern described for most angiosperms. Observation of bead-like globules and pollenkitt with a membraneous structure is presumed to be related to the addition of malachite green to the fixative.Copyright 1993, 1999 Academic Press
Felicia muricata (Thunb.) Nees, pollen, pollenkitt, ultrastructure, fixation