中度锰胁迫对降香黄檀幼苗光合特性的影响

Effects of Moderate Manganese Stress on Photosynthetic Characteristics of Dalbergia odorifera Seedlings

以降香黄檀幼苗为实验测试对象,通过便携式光合测定仪测定幼苗的净光合速率、蒸腾速率、气孔导度、胞间CO_(2)浓度等光合参数,探讨中度锰(10 mg/kg)胁迫对降香黄檀幼苗光合特性的影响。结果表明:在中度锰胁迫下,各胁迫时期降香黄檀幼苗的净光合速率、蒸腾速率、水分利用率和光能利用率均值同对照组比均降低;气孔导度均值在胁迫早期和中期比对照组低,后期则高于对照组;胞间CO_(2)浓度均值在3个胁迫时期同对照组比均有所升高。因此,可推测引起净光合速率下降的因素为非气孔限制因素。

Taking Dalbergia odorifera seedlings as the experimental test object,the net photosynthetic rate,transpiration rate,stomatal conductance,intercellular CO_(2) concentration and other photosynthetic parameters of the seedlings were measured with a portable photosynthetic tester to explore the effects of moderate manganese(10 mg/kg)stress on the photosynthetic characteristics of Dalbergia odorifera seedlings.The results showed that under moderate manganese stress,the net photosynthetic rate,transpiration rate,water use efficiency and light energy use efficiency of Dalbergia odorifera seedlings in each stress period were lower than those in the control group;The mean value of stomatal conductance in the early and middle stages of stress was lower than that of the control group,and higher than that in the control group in the late stages;The mean value of intercellular CO_(2) concentration in the three stress periods was higher than that in the control group.Therefore,it can be inferred that the non stomatal limiting factor is the factor causing the decline of net photosynthetic rate.