Ruhland Christopher T, Fogal Mitchell J, Buyarski Christopher R, Krna Matthew A
Department of Biological Sciences, TS-242 Trafton Sciences Center, Minnesota State University, Mankato, MN 56001, USA.
Molecules. 2007 Jun 29;12(6):1220-32. doi: 10.3390/12061220.
We examined the influence of solar ultraviolet-B radiation (UV-B; 280-320 nm) on the maximum photochemical efficiency of photosystem II (F(v)/F(m)), bulk-soluble phenolic concentrations, ferric-reducing antioxidant power (FRAP) and growth of Avena sativa. Treatments involved placing filters on frames over potted plants that reduced levels of biologically effective UV-B by either 71% (reduced UV-B) or by 19% (near-ambient UV-B) over the 52 day experiment (04 July-25 August 2002). Plants growing under near-ambient UV-B had 38% less total biomass than those under reduced UV-B. The reduction in biomass was mainly the result of a 24% lower leaf elongation rate, resulting in shorter leaves and less total leaf area than plants under reduced UV-B. In addition, plants growing under near-ambient UV-B had up to 17% lower F(v)/F(m) values early in the experiment, and this effect declined with plant age. Concentrations of bulk-soluble phenolics and FRAP values were 17 and 24% higher under near-ambient UV-B than under reduced UV-B, respectively. There was a positive relationship between bulk-soluble phenolic concentrations and FRAP values. There were no UV-B effects on concentrations of carotenoids (carotenes + xanthophylls).
我们研究了太阳紫外线B辐射（UV-B；280 - 320纳米）对燕麦光系统II最大光化学效率（F(v)/F(m)）、总可溶性酚类物质浓度、铁还原抗氧化能力（FRAP）以及生长的影响。实验处理包括在盆栽植物上方的框架上放置滤光片，在为期52天的实验（2002年7月4日至8月25日）中，这些滤光片将生物有效UV-B水平分别降低了71%（降低UV-B）或19%（接近环境UV-B）。生长在接近环境UV-B条件下的植物总生物量比生长在降低UV-B条件下的植物少38%。生物量的减少主要是由于叶片伸长率降低了24%，导致叶片比生长在降低UV-B条件下的植物更短，总叶面积更小。此外，在实验初期，生长在接近环境UV-B条件下的植物F(v)/F(m)值低达17%，且这种影响随植物年龄增长而减弱。总可溶性酚类物质浓度和FRAP值在接近环境UV-B条件下分别比在降低UV-B条件下高17%和24%。总可溶性酚类物质浓度与FRAP值之间存在正相关关系。UV-B对类胡萝卜素（胡萝卜素 + 叶黄素）浓度没有影响。
