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作 者 ：倪穗1;2;俞慧娜2;刘鹏2;徐根娣2

期 刊 ：植物营养与肥料学报 2007年 13卷 6期 页码：1135-1142

关键词：锰浓度；大豆；光合特性；基因型差异；

Keywords:Mn concentration, soybean, photosynthesis, genotype difference,

摘 要 ：采用溶液培养方法,设Mn²⁺浓度为0、0.05、0.50、5、30、50.mg/L,探讨了2种大豆品种(浙春2号、东北大豆854-11)的幼苗光合特性对不同锰浓度的响应。结果表明,低锰浓度提高了大豆叶片的初始荧光(F_o)、最大荧光(F_m)、PSⅡ原初光能转化效率(F_v/F_m)、潜在光化学活性(F_v/F_o)和光化学猝灭系数(qP),高锰降低了F_o、F_m、F_v/F_m、F_v/F_o、qP。随着锰营养的增加,非光化学猝灭系数(qN)增大。适量的锰浓度显著提高了大豆的净光合速率(P_n)、蒸腾速率(T_r)、气孔导度(G_s),降低了气孔阻力(R_s)和细胞间CO₂浓度(C_i),随着锰浓度的逐渐增大,降低了P_n、T_r、G_s,提高了R_s、C_i。0.50.mg/L下的锰浓度有最大的F_o,5.mg/L下的锰浓度有最大的F_m、qP、F_v/F_m、F_v/F_o,表明0.505～mg/L的锰浓度有利于大豆的光合作用。在50.mg/L的锰浓度下,两个大豆品种有最大的qN、R_s、C_i和最小的T_r、P_n,此时两个品种大豆耗散了过剩的激发能,降低了大豆叶片的光合速率,对大豆已产生了一定的伤害。两个品种大豆光合特性对锰的响应存在着基因型差异,浙春2号较东北大豆耐锰胁迫。

Abstract:With two soybean(Glycine max) varieties,Dongbei 85411(DB854-11) and Zhechun No.2(ZC2) as experimental materials,the responses of photosynthetic characteristics in soybean leaves to different manganese(Mn) concentration(0,0.05,0.5,5,30,50 mg/L) were studied.The results showed that minimal fluorescence(F_o),maximum fluorescence(F_v),maximal photochemical efficiency of PSⅡ(F_v/F_m),the potential activities of PSⅡ(F_v/F_o),photochemical quenching(qP) were enhanced with low concentration of Mn,but the F_o,F_m, F_v/F_m,F_v/F_o,qP were reduced with high concentration of Mn.With the increasing of Mn concentration,non-photochemical quenching coefficient(qN) was increased.Appropriate concentration of Mn significantly increased photosynthetic rate(P_n),transpiration rate(T_r),stomatal conductance(G_s) and decreased stomata resistance(R_s) and intercellular CO2 concentration(C_i).With the increasing of Mn concentration,P_n,T_r and G_s in soybean leaves were reduced,while R_s,C_i increased.F_o reached the maximum value at the concentration of 0.5 mg/L Mn²⁺,but F_m,qP,F_v/F_m,F_v/F_o was maximum at 5 mg/L Mn²⁺,which indicated that for the photosynthesis was promoted when the concentration of Mn²⁺ between 0.5 mg/L and 5 mg/L.Under 50 mg/L Mn²⁺treatment,qN,R_s,C_i reached the maximum and T_r,Pn reduced to the minimum. The negative effect on soybean growth was resulted from the dissipation of excess light energy and reduction of photosynthetic rate.There was a genotypic difference between the two varieties of soybean.Zhechun No.2 was more Mn-tolerant than Dongbei 854-11 soybean.

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