Department of Biology, University of Winnipeg, Winnipeg, MB, Canada.
Photochem Photobiol. 2013 Jan-Feb;89(1):103-10. doi: 10.1111/j.1751-1097.2012.01197.x. Epub 2012 Aug 2.
We examined the effects of daily exposure to UVB on growth, reproduction and histological characteristics of Daphnia magna over two generations at 20, 22, 25 and 30°C. Animals were exposed to 16 h of UVA and photosynthetically active radiation daily. Treated animals received 6 h of UVB during the light phase. Parental (P) generation growth and reproduction was impaired by exposure to UVB at all temperatures, with the poorest production at 30°C. First brood size decreased with UVB exposure; it was lowest at 30°C. Although F1 length at birth increased with P generation age, F1 produced by UVB-exposed mothers were smaller at all temperatures. The F1 generation was followed at 20 and 25°C; at both temperatures UVB exposure reduced F1 growth and reproduction. F1 growth and F2 production were lowest when both P and F1 generations were exposed to UVB. UVB exposure damaged ovarian and gut tissue at both 25 and 30°C; the consequences of this exposure were more severe at 30°C. The observed tissue damage may relate directly to the UVB-induced impairment of growth and reproduction. This study provides new insights into the effects of UVB on an important component of the pelagic zooplankton.
我们研究了在 20、22、25 和 30°C 下，经过两代 16 小时的长波紫外线（UVA）和光合有效辐射处理后，每日暴露于中波紫外线（UVB）对大型溞生长、繁殖和组织学特征的影响。处理组动物在光照阶段接受 6 小时的 UVB。在所有温度下，UVB 暴露都损害了亲代（P）代的生长和繁殖，在 30°C 时繁殖能力最差。第一代的繁殖数量随 UVB 暴露而减少，在 30°C 时最低。虽然 F1 出生时的体长随 P 代年龄的增加而增加，但在所有温度下，经 UVB 暴露的亲代所产的 F1 体型较小。在 20 和 25°C 下继续进行了 F1 代的研究；在这两个温度下，UVB 暴露都降低了 F1 的生长和繁殖。当 P 和 F1 两代都暴露于 UVB 时，F1 的生长和 F2 的繁殖率最低。在 25 和 30°C 时，UVB 暴露都损伤了卵巢和肠道组织；在 30°C 时，这种暴露的后果更为严重。观察到的组织损伤可能与 UVB 诱导的生长和繁殖受损直接相关。本研究为了解 UVB 对浮游性浮游动物这一重要组成部分的影响提供了新的见解。
