Shi Qinghua, Zhu Zhujun, Ying Quansheng, Qian Qiongqiu
Key Laboratory of Horticultural Plant Development and Biotechnology of Agriculture Ministry, Department of Horticulture, Zhejiang University, Hangzhou 310029, China.
Ying Yong Sheng Tai Xue Bao. 2005 Jun;16(6):1047-50.
By a solution culture experiment, this paper studied the effects of excess Mn on the growth, chlorophyll content, chlorophyll fluorescence parameters and photosynthesis of cucumber under different light intensity. The results indicated that excess Mn inhibited plant growth, which was more obvious under high light intensity than under low light intensity. The primary maximum photochemical efficiency of PSII (v/Fm), quantum efficiency of non-cyclic electron transport of PSII (phiPSII), and photochemical quenching (qP) were significantly decreased in excess Mn treatment under high light intensity, while no significant effects on Fv/Fm and qP were observed under low light intensity. Excess Mn, particularly under high light intensity, decreased net photosynthetic rate (Pn) and stomatal conductance (Gs). Excess Mn increased intracellular CO2 (Ci) under high light intensity and decreased Ci under low light intensity, while stomatal limitation value (Ls) was just reverse to Ci. It could be concluded that the decrease of Pn in excess Mn treatment was not resulted from stomatal limitation under high light intensity, but was true under low light intensity.
通过溶液培养试验，研究了不同光照强度下过量锰对黄瓜生长、叶绿素含量、叶绿素荧光参数及光合作用的影响。结果表明，过量锰抑制植株生长，在高光强下比在低光强下更明显。高光强下过量锰处理使PSII的初始最大光化学效率（Fv/Fm）、PSII非循环电子传递量子效率（ΦPSII）和光化学猝灭（qP）显著降低，而低光强下对Fv/Fm和qP无显著影响。过量锰，尤其是在高光强下，降低了净光合速率（Pn）和气孔导度（Gs）。高光强下过量锰使胞间CO2（Ci）增加，低光强下Ci降低，而气孔限制值（Ls）与Ci相反。可以得出结论，过量锰处理下Pn的降低在高光强下不是由气孔限制引起的，而在低光强下是由气孔限制引起的。
