【摘要】 在自然条件下,增加不同强度的UV B辐射,对攀援植物丝瓜叶片光合速率日变化和水分利用效率进行了研究,发现经增加R1强度UV B辐射处理的丝瓜的净光合速率和蒸腾速率比对照上升了28%和33%,水分利用效率则下降了3 4%,而经增加R2强度UV B辐射处理的丝瓜的净光合速率和蒸腾速率比对照上升了47%和13%,水分利用效率也上升了28%,且其光合作用不受午间强光的抑制,光合午休现象消失了.这表明,在该实验的UV B强度下,丝瓜的光合作用不但未受抑制,反而还增强了,说明适当增加UV B辐射对丝瓜的生长有利.更多还原

【Abstract】 Under natural conditions,diurnal changes of photosynthetic rate and water use efficiency of loofah exposed to different intensities of UVB radiation were studied. Compared to the controled treatment group, the photosynthetic rate and transpiration rate of plants subjected to R1 dose UVB radiation were increased by 28% and 33%, respectively,but the water use efficiency was decreased by 34%. The photosynthetic rate and transpiration rate of plants subjected to R2 dose UVB radiation were increased by 47% and 13%, respectively,and the water use efficiency was increased by 28%. Moreover, for plants subjected to R2 treatment, the photosynthesis wasnt inhibited by the strong light at noon. This indicated that the photosynthetic rate of loofah wasnt inhibited under the UVB radiation which loofah exposed to in this experiment. However, appropriate UVB radiation was beneficial to the growth of loofah.更多还原