咬人狗、蝎子草和咬人貓葉部焮毛與相關表皮構造的比較

Comparative Study on the Stinging Trichomes and Some Related Epidermal Structures in the Leaves of Dendrocnide meyeniana, Girardinia diversifolia, and Urtica thunbergiana

本研究比較咬人狗、蠍子草和咬人貓的焮毛與相關表皮構造形態與分佈上的異同。在葉部上下表皮中可以發現到焮毛、腺毛和非腺毛（硬狀毛茸與表面瘤狀毛茸）的存在。在研究中觀察到咬人狗的焮毛最短，但在上表皮的密度最高；蠍子草的焮毛最長，密度卻最低。焮毛細胞內含的主要元素為矽和鈣。咬人狗的平均矽/鈣比最高，而咬人貓下表皮葉脈上的焮毛細胞平均矽/鈣比最低。蓮座細胞的數量與覆蓋程度以蠍子草最多，咬人狗最少。咬人貓葉表並沒有發現泌水器，三者中只有咬人狗葉表上發現珍珠狀腺體存在。碳酸鈣與草酸鈣沈澱都可以在這三種植物葉子中找到。

In this study, the morphology and distribution of the stinging trichomes and the related epidermal structures in the mature leaves of Dendrocnide meyeniana, Girardinia diversifolia, and Urtica thunbergiana are compared. On the adaxial and abaxial leaf surfaces, stinging trichomes, glandular, and non-glandular (hispid and pustulate) were observed. Among these studied species, the stinging trichome of Dendrocnide meyeniana is the shortest, but the density on the adaxial surface is the highest. In Girardinia diversifolia, the stinging trichomes are the longest, but the density is the lowest. The major elements of stinging cells of all the studied plants are silicon and calcium. In Dendrocnide meyeniana, the average silicon/calcium ratio is the highest, while the lowest silicon/calcium ratio was found in the stinging cells located on the veins of abaxial surface in Urtica thunbergiana. In Girardinia diversifolia, the amount and surrounding area of pedestal cells are the highest while in Dendrocnide meyeniana, however, are the lowest. On the leaf surface of Urtica thunbergiana, not any hydathode was observed, while pearl glands were only found in the leaves of Dendrocnide meyeniana. Calcium carbonate and oxalate depositions were found in all the studied stinging species.