Rousseaux M Cecilia, Julkunen-Tiitto Riitta, Searles Peter S, Scopel Ana L, Aphalo Pedro J, Ballaré Carlos L
IFEVA, Consejo Nacional de Investigaciones Científicas y Técnicas and Universidad de Buenos Aires, Av. San Martín 4453, C1417 DSE, Buenos Aires, Argentina.
Oecologia. 2004 Mar;138(4):505-12. doi: 10.1007/s00442-003-1471-5. Epub 2004 Jan 22.
We examined the effects of solar ultraviolet-B (UV-B) radiation on plant-insect interactions in Tierra del Fuego (55 degrees S), Argentina, an area strongly affected by ozone depletion because of its proximity to Antarctica. Solar UV-B under Nothofagus antarctica branches was manipulated using a polyester plastic film to attenuate UV-B (uvb-) and an Aclar film to provide near-ambient UV-B (uvb+). The plastic films were placed on both north-facing (i.e., high solar radiation in the Southern Hemisphere) and south-facing branches. Insects consumed 40% less leaf area from north- than from south-facing branches, and at least 30% less area from uvb+ branches than from uvb- branches. The reduced herbivory on leaves from uvb+ branches occurred for both branch orientations. Leaf mass per area increased and relative water content decreased on north- versus south-facing branches, while no differences were apparent between the UV-B treatments. Solar UV-B did lead to lower gallic acid concentration and higher flavonoid aglycone concentration in uvb+ leaves relative to uvb- leaves. Both the flavonoid aglycone and quercetin-3-arabinopyranoside were higher on north-facing branches. In laboratory preference experiments, larvae of the dominant insect in the natural community, Geometridae "Brown" (Lepidoptera), consumed less area from field-grown uvb+ leaves than from uvb- leaves in 1996-97, but not in 1997-98. Correlation analyses suggested that the reduction in insect herbivory in the field under solar UV-B may be mediated in part by the UV-B effects on gallic acid and flavonoid aglycone.
我们研究了太阳紫外线B（UV-B）辐射对阿根廷火地岛（南纬55度）植物与昆虫相互作用的影响，该地区因靠近南极洲而受到臭氧消耗的严重影响。使用聚酯塑料薄膜来减弱UV-B（uvb-），并使用阿克莱尔薄膜来提供接近环境水平的UV-B（uvb+），以此来控制南极洲假山毛榉树枝下的太阳UV-B。塑料薄膜被放置在朝北（即南半球太阳辐射强）和朝南的树枝上。昆虫从朝北树枝上消耗的叶面积比朝南树枝上少40%，从uvb+树枝上消耗的面积比uvb-树枝上至少少30%。两种树枝方向上，uvb+树枝上叶片的食草作用都有所降低。与朝南树枝相比，朝北树枝上单位面积的叶质量增加，相对含水量降低，而UV-B处理之间没有明显差异。相对于uvb-叶片，太阳UV-B确实导致uvb+叶片中的没食子酸浓度降低，黄酮苷元浓度升高。黄酮苷元和槲皮素-3-阿拉伯吡喃糖苷在朝北树枝上的含量都更高。在实验室偏好实验中，自然群落中占主导地位的昆虫尺蛾科“棕色”（鳞翅目）的幼虫，在1996 - 1997年从田间种植的uvb+叶片上消耗的面积比uvb-叶片上少，但在1997 - 1998年并非如此。相关分析表明，太阳UV-B照射下田间昆虫食草作用的降低可能部分是由UV-B对没食子酸和黄酮苷元的影响介导的。
