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Studies on Sporopollenin Structure during Pollen Development

To clarify whether the structure of sporopollenin varies during pollen development FTIR and 13C NMR spectroscopic analyses of Tulipa and Cucurbita sporopollenin from three different developmental stages were carried out. The spectra of sporopollenin obtained from an early, a middle postmeiotic and the mature stage have been compared. The assumption that sporopollenin mainly consists of long chain aliphatics with varying amounts of aromatics is corroberated by our results. Only slight changes in sporopollenin structure could be recognized during pollen wall development of Cucurbita maxima. In contrast to this the spectra of Tulipa sporopollenin of the three developmental stages exhibited significant differences concerning the aliphatic and aromatic components.