This study investigates the molecular, carbon, and hydrogen isotope compositions of n-alkanes in eight pairs of a holoparasitic plant (Cuscuta chinensis) and its hosts. It is unexpected that C. chinensis has a higher concentration of n-alkanes than its hosts in seven of the eight pairs, and it is preferentially dominated by n-C₂₉ alkane (representing > 75% of the total n-alkanes). In addition, the δ¹³C values of C₂₉ alkane in C. chinensis are less negative (avg. 1.8 ‰) than those in the hosts, while the δ²H values of C₂₉ alkane are more negative in C. chinensis (the difference averages 48 ‰). We propose that the ²H-depletion of n-alkanes in the stem parasite C. chinensis may result from the utilization of stem water with less influence from evapotranspiration or the use of newly synthesized carbohydrates which is ²H-depleted relative to stored sugars. These results highlight the importance of plant nutrient status on the molecular and isotopic compositions of leaf waxes, which shed light on the (paleo)ecological potential of leaf wax δ²H values.

本研究探讨的分子，碳和氢同位素组成Ñ在8对一个holoparasitic植物（的烷烃菟丝子）及其主机。出乎意料的是黄连具有更高浓度的ñ -烷烃比其在八对七个主机，并且它优选地由主导Ñ -C ₂₉烷烃（占>总量的75％ñ -链烷烃）。此外，δ ¹³的C C值₂₉烷烃黄连不太负（平均1.8‰）比在主机，而δ ²的Cħ值₂₉C. chinensis中烷烃的阴性性更高（平均差异为48‰）。我们建议，²的H-耗尽Ñ在干寄生虫-烷烃黄连可以从干水的利用导致与来自蒸散影响较少或使用新合成的碳水化合物，其是² H-贫相对于存储糖。这些结果强调在叶蜡的分子和同位素组成，其上的（古）生态叶蜡的δ潜在揭示的植物营养状态的重要性^2个ħ值。