Seel W E, Press M C
School of Biological Sciences, Williamson Building University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
New Phytol. 1994 May;127(1):37-44. doi: 10.1111/j.1469-8137.1994.tb04257.x.
Light saturated rates of photosynthesis (A ), water use-efficiency (WUE) and photosynthetic nitrogen use-efficiency (PNUE) were measured for three sub-Arctic annual root hemiparasites (Rhinanthus minor L., Euphrasia frigida L. and Melampyrum sylvaticum L.) growing in the Torneträsk region of Swedish Lapland. Photosynthesis and resource use-efficiency of the hemiparasites were dependent on (i) attachment to a host and (ii) the nature of the host to which attachment was made. The highest rates of A were recorded in those hemiparasites attached to legumes and the lowest rates were recorded in those which were not attached to a host. Intermediate rates of A were recorded in hemiparasites attached to grasses. A and leaf conductance were more closely related in attached than in unattached hemiparasites, WUE was greatest in those hemiparasites attached to legumes, but was not a simple function of nitrogen supply. PNUE was greater in attached than in unattached plants, but was inversely related to the total-nitrogen concentration of the leaves. In an earlier paper we demonstrated that the growth of these hemiparasites is highly host dependent. Here we demonstrate that the carbon, nitrogen and water relations of these plants are also highly host dependent.
在瑞典拉普兰的托内特拉斯克地区，对三种亚北极一年生根部半寄生植物（小鼻花、寒小米草和林地山萝花）的光合作用光饱和速率（A）、水分利用效率（WUE）和光合氮利用效率（PNUE）进行了测定。半寄生植物的光合作用和资源利用效率取决于：（i）与寄主的附着，以及（ii）所附着寄主的性质。附着在豆科植物上的半寄生植物的A值最高，未附着寄主的半寄生植物的A值最低。附着在禾本科植物上的半寄生植物的A值处于中间水平。与未附着的半寄生植物相比，附着的半寄生植物的A值与叶片导度的关系更为密切，附着在豆科植物上的半寄生植物的WUE最高，但它并非氮供应的简单函数。附着植物的PNUE高于未附着植物，但与叶片总氮浓度呈负相关。在较早的一篇论文中，我们证明了这些半寄生植物的生长高度依赖寄主。在此，我们证明了这些植物的碳、氮和水分关系也高度依赖寄主。
