铁胁迫对蕨麻叶绿素荧光及生理特性的影响

Effects of Iron Stress on Chlorophyll Fluorescence and Physiological Characteristics of Potentilla Anserina L.

为研究铁胁迫对蕨麻(Potentilla anserina L.)光合生理的影响,寻找适合蕨麻进行光合作用的铁浓度。以‘青海蕨麻3号’为试验材料,设置0(F_(0)),12.5(F_(1)),25.0(F_(2)),75.0(F_(6)),125.0μmol·L^(-1)(F_(10))共5个铁浓度,进行盆栽试验。测定5种铁浓度处理下蕨麻的相对叶绿素含量、叶绿素荧光参数及部分生理指标,并采用主成分分析探究铁对蕨麻的综合影响。研究结果表明:与对照相比,F_(1)、F_(2)、F_(6)显著提高了蕨麻的相对叶绿素含量。铁浓度对蕨麻叶绿素荧光参数有较大影响,随着铁浓度的不断增加,原初光化学效率(Fv/Fm)、实际量子产量[Y(Ⅱ)]和光化学淬灭系数(qP)先升高后降低,其中,Fv/Fm在F_(2)处理下有最大值,Y(Ⅱ)和qP在F_(6)处理下有最大值;随着铁浓度的升高,非调节性能量耗散的量子产量[Y(NO)]逐渐增大,但供铁组Y(NO)均显著低于对照组。光响应拟合参数中,最大电子传递速率(ETRm)在F_(6)处理时有最大值,F_(2)处理下半饱和光强(Ik)显著高于其他处理。对所有光合数据进行主成分分析后,排序由大到小依次为:F_(6)>F_(2)>F_(1)>F_(10)>F_(0)。F_(6)(75.0μmol·L^(-1))处理时蕨麻的总体光合性能最优。合适的铁浓度可提高蕨麻叶片叶绿素含量,增强光系统活性,并改善蕨麻的光合特性。

To investigate the effect of iron stress on the photosynthetic physiological characteristics and find the iron concentration suitable for photosynthesis of Potentilla anserine L.Using'Qinghai Juema No.3'as the test material,a pot experiment was carried out with 5 iron concentrations of 0(F_(0)),12.5(F_(1)),25.0(F_(2)),75.0(F_(6)),and 125.0μmol·L^(-1)(F_(10)).The relative chlorophyll content,chlorophyll fluorescence parameters and partial physiological indicators of Potentilla anserine L.leaves were determined and then evaluated by principal component analysis.The finding showod that compared with the CK treatment,the F_(1),F_(2) and F6 treatments increased the relative chlorophyll content of Potentilla anserine L.leaves significantly.Iron concentration had a significant influence on the chlorophyll fluorescence parameters of Potentilla anserina L.With the continuous increase of iron concentration,primary photochemical efficiency(Fv/Fm),actual quantum yield[Y(Ⅱ)]and photochemical quenching coefficient(qP)shoed a trend of increasing first and then decreasing.Among them,Fv/Fm had the largest value at the F2 treatment.The Y(II)and qP had the largest values in F6 treatment;quantum yield of non-regulatory energy dissipation[Y(NO)]gradually increasing with the increase of iron concentration,but these treatments which supply iron were significantly lower than the control group.Among the light response fitting parameters,maximum electron transport rate(ETRm)had the largest value under F6 treatment,and half-saturation light intensity(Ik)was significantly higher under F2 treatment.The result of principal component comprehensive ranking was F_(6)>F_(2)>F_(1)>F_(10)>F0.The whole photosynthetic performance of Potentilla anserine L.was the best in F6(75.0μmol·L^(-1))treatment.Proper concentration of iron could increase chlorophyll content,enhance photosystem activity,and improve photosynthetic characteristics of Potentilla anserine L.