摘要或動機

蓮花效應是指蓮葉表面具有奈米纖毛結構，因此只要葉面稍微傾斜，水珠就會滾離葉面，在我們生活週遭，許多植物具有蓮花效應。本實驗選擇彩葉山漆莖作為研究材料，因為我們發現在同一植株上，嫩葉的蓮花效應最佳，而老葉幾乎無蓮花效應。當彩葉山漆莖的新葉轉為老葉，蓮花效應會減弱，甚至消失。我們以不同水量、土壤酸鹼值及光照作為變因，來探討蓮花效應改變的原因，結果發現水量並非主要影響蓮花效應改變的變因；土壤過酸或過鹼，會減弱新葉及嫩葉的蓮花效應；置於暗室則使整株彩葉山漆莖所有葉面皆無蓮花效應。許多植物的性狀，在老化或面臨環境改變時，會將控制性狀的基因開啟或關閉。因此，我們推論，當環境因子改變時，植物的蓮花效應可能是經由基因層次的調控，藉以增強或減弱此性狀的表現。如果不是基因的開啟或關閉，則有可能僅是葉表面的結構發生些微的改變，真正詳細的機制仍有待進一步的確認。;We choose Breynia nivosa (Bull ex W. G. Smith) Small as a model plant to study the lotus effect on the leaves for the reason that on the same chosen plant the new-born leaves have the best lotus effect while the elder ones have little lotus effect. When the new leaves turns into elder ones, the lotus effect also turns weaker or even vanishes. To explore the exact mechanisms, we take water quantity、soil pH、and light density as the experimental factors. The results show that water quantity cannot affect the lotus effect on all leaves, change in soil pH can decrease the lotus effect on the new and new-born leaves, and dark treatments can eliminate the lotus effect on all leaves. When the environments change, the phenotypes of plants could also be changed to adapt to the new conditions by turning on or off genes. Therefore, we suggest that the lotus effect on the leaves is also controlled by genes to increase or decrease its phentype so as to adapt to the changing environments. If not, it may simply be a little change of the surface structure of the leaves. The detailed mechanism remains to be confirmed further.