A palynological study of the genus indigofera (Leguminosae) in Taiwan

Abstract

The pollen of 15 species of Indigofera from Taiwan was studied by means of light microscopy, scanning electron and transmission electron microscopy. The pollen of these species is classified into five types on the basis of exine structure, perforations, shape of tectum channels, granular or columellate interstitium, and prominent or reduced foot layer. Subdivisions of each type are based on the ornamentation of the tectate surface on the apocolpia and the mesocolpia. It is suggested that Type I is the most primitive and that Type II has evolved from it. Type II has undergone a multiplication of granules, an elaboration of the tectum and a reduction of foot layer to form the most complex Type III. Type II has also evolved towards a modification of the columellae to form the lamellate interstitium of Type IV. Through a reduction of the lamellate granular layer of Type IV the single granular layer of Type V has formed. It is also possible that Type 1.3 has undergone a reduction of the columellae to produce the single granular interstitium of Type V. Pollen data can be used, in the identification of some of the Indigofera species of Taiwan. © 1995 Scandinavian University Press.