Feldheim Kevin, Conner Jeffrey K
Department of Ecology, Ethology, and Evolution, University of Illinois, Shelford Vivarium, 606 E. Healey St., 61820, Champaign, IL, USA.
Oecologia. 1996 May;106(3):284-297. doi: 10.1007/BF00334556.
The increasing levels of ultraviolet-B (UV-B) radiation reaching the earth's surface caused by ozone destruction have prompted many studies of UV-B effects on plants. Most of these studies have focused on physiological and growth responses of plants to increased UV-B, but these measures may not be closely related to future survival of plant populations. We examined the effects of two different levels of increased UV-B on total female fitness, including seed number and quality, in rapid-cycling strains of Brassica nigra and B. rapa (Brassicaceae). We also measured the effects of UV-B on fitness components, particularly those related to pollination success. Two separate experiments, examining two different levels of UV-B, were performed. Sixty plants of each species were grown under control and enhanced levels of UV-B for a total of 480 plants (60 plantsx2 speciesx2 UV-B levelsx2 experiments). Increased UV-B was generally detrimental to growth and flowering in both species; however, total seed production was actually greater at higher UV-B doses in three of four dose/plant species combinations examined. UV-B had little effect on pollination success or offspring quality in either species. Therefore, in spite of the detrimental effects of UV-B on growth and flowering that we found, there is little evidence that fitness of these plant species would suffer with increasing UV-B, and we caution against using solely physiological or growth measurements to infer effects of UV-B on plant population fitness.
臭氧层破坏导致到达地球表面的紫外线 - B（UV - B）辐射水平不断增加，这促使人们对UV - B对植物的影响展开了许多研究。这些研究大多聚焦于植物对增加的UV - B的生理和生长反应，但这些指标可能与植物种群未来的生存没有密切关联。我们研究了两种不同水平增加的UV - B对黑芥和白菜型油菜（十字花科）快速循环品系中总的雌性适合度（包括种子数量和质量）的影响。我们还测量了UV - B对适合度组成部分的影响，特别是那些与授粉成功相关的部分。进行了两项独立实验，研究两种不同水平的UV - B。每个物种的60株植物分别在对照和增强的UV - B水平下生长，总共480株植物（60株植物×2个物种×2个UV - B水平×2项实验）。增加的UV - B通常对两个物种的生长和开花都有不利影响；然而，在所研究的四个剂量/植物物种组合中的三个组合中，在较高的UV - B剂量下，总的种子产量实际上更高。UV - B对两个物种的授粉成功率或后代质量几乎没有影响。因此，尽管我们发现UV - B对生长和开花有不利影响，但几乎没有证据表明这些植物物种的适合度会随着UV - B的增加而受到影响，我们提醒不要仅使用生理或生长测量来推断UV - B对植物种群适合度的影响。
