Study of pollen brush in selected species of Astragalus L. subgenus Pogonophace Bunge (Leguminosae)

The styles of four species within Astragalus subgenus Pogonophace (Leguminosae) were investigated under the scanning electron microscope (SEM): A. hoantchy Franch., A. complanatus Bunge, A. flavovirens K. T. Fu and A. dolichochaete Diels. The first species has a penicillate stigma, while the others possess a pollen brush. The two types of styles are not homologous. The results support the exclusion of sect. Sesbanella from subg. Pogonophace and the treatment of the other three sections of the subgenus as a distinct genus (Phyllolobium) in subtribe Coluteinae (tribe Galegeae), which is consistent with previous morphological and molecular studies.