Heraud Philip, Beardall John
School of Biological Sciences, Monash University, Wellington Road, Clayton, Melbourne 3800, Australia.
J Photochem Photobiol B. 2002 Nov;68(2-3):109-16. doi: 10.1016/s1011-1344(02)00380-9.
A 30-min exposure to UV-B radiation (1.1 Wm(-2), unweighted) from a xenon arc lamp caused pronounced inhibition (33-78%) of net photosynthetic oxygen production in three species of microalgae, Phaeodactylum tricornutum Bohlin, Dunaliella tertiolecta Butcher and Wolozynskia sp., however, no statistical differences (t-test, alpha=0.05) in dark-respiration rates were found between the control group and the UV-treated group, for any of the species tested. These results indicate: (i) that the respiratory processes responsible for oxygen consumption do not sustain any appreciable impairment registered in the first half-hour after ultraviolet radiation (UVR) exposure; and (ii) any change in respiration that may occur in response to increased repair demands is not detected in this period. Dark-respiration rates were observed to be significantly higher in all species tested (17-29%; t-test, alpha=0.05) following illumination with photosynthetically active radiation, compared to dark-respiration before illumination. This increase, interpreted as enhanced post-illumination respiration (EPIR), was observed in all three species. The magnitude of this increase was not affected by prior exposure to UVR.
用氙弧灯进行30分钟的UV - B辐射（1.1 Wm(-2)，未加权），导致三种微藻——三角褐指藻（Phaeodactylum tricornutum Bohlin）、杜氏盐藻（Dunaliella tertiolecta Butcher）和沃洛津斯基藻（Wolozynskia sp.）的净光合产氧量受到显著抑制（33 - 78%）。然而，对于所测试的任何物种，对照组和UV处理组之间在暗呼吸速率上均未发现统计学差异（t检验，α = 0.05）。这些结果表明：（i）负责氧气消耗的呼吸过程在紫外线辐射（UVR）暴露后的前半小时内未受到任何明显损害；（ii）在此期间未检测到因修复需求增加而可能发生的呼吸变化。与光照前的暗呼吸相比，在用光合有效辐射照射后，所有测试物种的暗呼吸速率均显著更高（17 - 29%；t检验，α = 0.05）。这种增加被解释为光照后呼吸增强（EPIR），在所有三个物种中均观察到。这种增加的幅度不受先前UVR暴露的影响。
