Pollen morphology of Taiwanese Asparagaceae species: insights from scanning electron microscopy

Abstract

This study employed scanning electron microscopy to investigate the pollen morphology of Taiwanese Asparagaceae species, revealing that their pollen morphology closely aligns with that of other monocotyledonous plant taxa such as Asparagales, Commelinales, and Bromeliales. Despite the overall similarity, variations in pollen morphology across different genera were noted, highlighting its potential utility in classification. Unlike the wide diversity observed in flower morphology, Asparagaceae pollen morphology appears conservative, rendering it less effective as a taxonomic marker at the species level. The study also delved into the effects of pollenkitt and harmomegathy on pollen morphology, discovering that pollenkitt partially or completely coats the pollen surface, potentially complicating the identification of exine sculpture. Furthermore, the harmomegathic effect was observed to influence aperture dynamics. Consequently, observing both hydrated and dried pollen is advisable, as it can more accurately depict the pollen's aperture morphology and offer additional insights for pollen grain analysis.