Department of Plant Physiology, Comenius University in Bratislava, Mlynská dolina B2, SK-842 15, Bratislava, Slovakia.
Plant Cell Environ. 2011 Nov;34(11):1865-73. doi: 10.1111/j.1365-3040.2011.02382.x. Epub 2011 Jul 21.
The pitcher plant Nepenthes ampullaria has an unusual growth pattern, which differs markedly from other species in the carnivorous genus Nepenthes. Its pitchers have a reflexed lid and sit above the soil surface in a tighly packed 'carpet'. They contain a significant amount of plant-derived materials, suggesting that this species is partially herbivorous. We tested the hypothesis that the plant benefits from leaf litter utilization by increased photosynthetic efficiency sensu stricto cost/benefit model. Stable nitrogen isotope abundance indicated that N. ampullaria derived around 41.7 ± 5.5% of lamina and 54.8 ± 7.0% of pitcher nitrogen from leaf litter. The concentrations of nitrogen and assimilation pigments, and the rate of net photosynthesis (A(N)), increased in the lamina as a result of feeding, but did not increase in the trap. However, maximal (F(v) /F(m)) and effective photochemical quantum yield of photosystem II (Φ(PSII)) were unaffected. Our data indicate that N. ampullaria benefits from leaf litter utilization and our study provides the first experimental evidence that the unique nitrogen sequestration strategy of N. ampullaria provides benefits in term of photosynthesis and growth.
猪笼草 Nepenthes ampullaria 的生长模式很不寻常，与肉食性猪笼草属的其他物种有明显的不同。它的瓶子有一个可弯曲的盖子，位于土壤表面之上，紧密地排列在“地毯”上。它们含有大量的植物衍生物质，表明该物种部分是食草性的。我们测试了一个假设，即植物通过增加严格意义上的光合作用效率成本/收益模型的叶片凋落物利用来获益。稳定的氮同位素丰度表明，N. ampullaria 从叶片凋落物中获得了约 41.7±5.5%的叶片和 54.8±7.0%的瓶身氮。由于摄食，叶片中的氮和同化色素的浓度以及净光合速率（A(N)）增加，但在陷阱中没有增加。然而，最大（F(v)/F(m)）和光系统 II 的有效光化学量子产量（Φ(PSII)）不受影响。我们的数据表明，N. ampullaria 从叶片凋落物的利用中获益，我们的研究首次提供了实验证据，表明 N. ampullaria 独特的氮固定策略在光合作用和生长方面提供了益处。
