부산대학교 도서관

Premise of research. While carrying out a taxonomic revision of Kaunia , uncommon types of trichomes and arrangement of trichomes on the leaves of Kaunia gynoxymorpha and Kaunia pachanoi were observed. Moreover, the trichome arrangement is not usual for either Kaunia or most of Eupatorieae. In this study, we aim to describe the leaf blade trichomes and indumentum in these two species and discuss, along with other anatomical characteristics, their ecological role and potential adaptation to dry environments. Methodology. We used traditional light microscopy, scanning electron microscopy, and fluorescence microscopy to examine leaf blade anatomical characteristics. We applied histochemical techniques to the leaves of both studied species to determine the presence of cutinized cell walls, which may influence apoplastic water flow in trichomes. Pivotal results. Our results show two-armed trichomes in K. gynoxymorpha that are unusual in the tribe Eupatorieae. The arrangement of glandular and nonglandular leaf trichomes of the two studied species in tufts of 3–10 trichomes, sunken in surface crypts, is also uncommon. Conclusions. These tufts of trichomes and other anatomical and histochemical evidence suggest that nonglandular trichomes and their arrangement in tufts in K. gynoxymorpha and K. pachanoi provide adaptive advantages by combining physical, mechanical, and biochemical functions to grant protection against drought and high light intensity, among other adverse conditions. [ABSTRACT FROM AUTHOR]