THE COMPOSITION OF SPOROPOLLENIN AND ITS USE IN LIVING AND FOSSIL PLANT SYSTEMATICS

Previous investigations of sporopollenin using C-13 Solid State Nuclea r Magnetic Resonance have demonstrated differences between the major g roups of plants in the composition of this acetolysis-resistant biomac romolecule. The work presented here corroborates these results and sug gests that sporopollenin obtained from seed megaspore-membranes differ s slightly from that of pollen from the same plant group. Spectra obta ined using NMR have been subjected to multivariate analysis. This appr oach has provided information which may be interpreted in phylogenetic terms. A number of fossil sporopollenins have also been investigated. These all show considerable degradation through diagenesis but retain certain characteristics of the original sporopollenin composition. Mi crospores and megaspores from the same species of Carboniferous arbore scent lycopsid have also been investigated with a view to discerning a ny differences in composition that may exist between these sources of sporopollenin in the fossil record. Investigation of the effects of ac etolysis on spore walls has also been undertaken. Together with the ab ove work, this contributes to our understanding of the chemical compos ition of sporopollenins and the way in which this substance is affecte d by a treatment commonly used in the preparation of exines.