Department of Zoology, University of Cambridge, Cambridge, UK.
Plant Signal Behav. 2009 Nov;4(11):1019-23. doi: 10.4161/psb.4.11.9664. Epub 2009 Nov 25.
Carnivorous pitcher plants of the genus Nepenthes capture prey with a pitfall trap that relies on a micro-structured, slippery surface. The upper pitcher rim (peristome) is fully wettable and causes insects to slip by aquaplaning on a thin water film. The high wettability of the peristome is probably achieved by a combination of hydrophilic surface chemistry, surface roughness and the presence of hygroscopic nectar. Insect foot attachment could be prevented by the delayed drainage of the thin water film between the adhesive pad and the surface. Drainage should be faster for insects with a hairy adhesive system; however, they slip equally on the wet peristome. Therefore the stability of the water film against dewetting appears to be the key factor for aquaplaning. New experimental techniques may help to clarify the detailed function of the pitcher plant peristome and to explore its potential for biomimetic applications.
猪笼草属的肉食性植物利用一种依赖于微结构、光滑表面的陷阱来捕捉猎物。上唇（缘）完全可润湿，并使昆虫在薄水膜上滑过，产生水漂现象。缘的高润湿性可能是由亲水性表面化学、表面粗糙度和吸湿花蜜的存在共同作用而实现的。昆虫足部的附着可能会被粘性垫和表面之间薄水膜的延迟排水所阻止。对于具有毛状粘性系统的昆虫，排水速度应该更快；然而，它们在湿润的上唇上同样会滑到。因此，抵抗去湿的水膜稳定性似乎是水漂现象的关键因素。新的实验技术可能有助于阐明猪笼草缘的详细功能，并探索其在仿生学应用中的潜力。
