Department of Biology, University of Oulu, PO Box 3000, FIN-90014 Oulu, Finland.
Physiol Plant. 2012 Aug;145(4):516-26. doi: 10.1111/j.1399-3054.2011.01559.x. Epub 2012 Jan 31.
The aim of this study was to investigate plant frost hardiness responses to ultraviolet (UV) radiation, since the few results reported are largely contradictory. It was hypothesized that functional adaptation of life forms could explain these contradictions. Dwarf shrubs and tree seedlings, representing both evergreen and deciduous forms, were tested (Vaccinium vitis-idaea, Vaccinium myrtillus, Pinus sylvestris, Betula pubescens and its red form f. rubra). The research was performed in Sodankylä, Northern Finland (67°N), with enhanced UV-B- and UV-A-radiation treatments between 2002 and 2009. Plant frost hardiness was determined using the freeze-induced electrolyte leakage method in early autumn, during the onset of the frost hardening process. Additional physiological variables (malondialdehyde, glutathione, total phenols, C and N contents) were analyzed in V. vitis-idaea to explain the possible responses. These variables did not respond significantly to UV-radiation treatments, but explained the frost hardiness well (r² = 0.678). The main finding was that frost hardiness decreased in the evergreen shrub V. vitis-idaea, particularly with enhanced UV-A radiation. No significant responses were observed with the other plants. Therefore, this study does not support the idea that enhanced UV radiation could increase plant frost hardiness.
本研究旨在探讨植物对紫外线（UV）辐射的抗寒响应，因为已有的少量研究结果存在很大的矛盾。我们假设，生活形态的功能适应可以解释这些矛盾。我们测试了小灌木和幼苗树种，它们分别代表常绿和落叶形式（Vaccinium vitis-idaea、Vaccinium myrtillus、Pinus sylvestris、Betula pubescens 及其红色形式 f. rubra）。该研究在芬兰北部的 Sodankylä（67°N）进行，在 2002 年至 2009 年期间进行了增强的 UV-B 和 UV-A 辐射处理。在秋季初霜开始时，采用冷冻诱导电解质渗漏法测定植物的抗寒性。在 V. vitis-idaea 中分析了其他生理变量（丙二醛、谷胱甘肽、总酚、C 和 N 含量），以解释可能的响应。这些变量对 UV 辐射处理没有显著响应，但很好地解释了抗寒性（r²=0.678）。主要发现是常绿灌木 V. vitis-idaea 的抗寒性降低，尤其是在增强的 UV-A 辐射下。其他植物没有观察到明显的响应。因此，本研究不支持增强的 UV 辐射会增加植物抗寒性的观点。
