Abstract: Fourier transform infrared (FTIR) spectroscopy was used to study the composition of pollen exine in five species of gymnosperm, including Ginkgo biloba L., Abies firma Sieb et Zucc., Cedrus deodara(Roxb.) G.Don, Cunninghamia lanceolata(Lamb.) Hook, and Cryptomeria japonica(L.f.) D.DON. The results showed that the infrared spectra of these pollen exines are mainly composed of the absorption bands of protein, lipids and polysaccharides, however, there were different components of pollen exine in these 5 species of gymnosperm. For example, there was much protein in pollen exine of G.biloba; rich lipids in pollen exine of Sonko; and polysaccharides in pollen exine of Taxodiaceae. In addition, there are significant differences in the spectra of different genus. Using scanning electron microscope, we observed that the pollens of C.deodara and A.firma are big in size, with two sacs. In contrast, the pollens of the other three species are small in size, without sacs. The surface of pollen exine in C.japonica and C.lanceolata showes orbicules, but that of C.deodara(Roxb.) G.Don and A.firma Sieb et Zucc shows the ornamentation of microgranulates with rough surfaceand smooth surface showing apertures.

Key words: gymnosperms plants, pollen, pollen exine component, FTIR, scanning electron microscopy observation