以芍药为试验材料,探讨了叶面喷施不同浓度铜肥对芍药叶片的光合色素含量、光合特性及荧光动力学参数的影响。结果表明:叶面喷施不同浓度铜肥的芍药叶绿素含量、光合特性及叶绿素荧光参数差异显著。不同处理的芍药光补偿点为6-12μmol/(m^2.s),光饱和点为500-1 000μmol/(m^2.s),CO2补偿点为60-90μmol/L,CO2饱和点为1 000-1 600μmol/mol,喷施400 mg/L铜肥处理的光饱和点、CO2饱和点、表观量子效率、羧化效率较高;不同处理的芍药光合速率日变化均呈单峰曲线,喷施200 mg/L、400 mg/L铜肥的处理净光合速率最高;喷施800 mg/L铜肥的处理表观量子效率、Fv/Fm值低于其他处理。叶面喷施铜肥对芍药光合作用具有显著影响,综合比较,在本试验条件下,铜浓度以400 mg/L为宜,浓度过高则对光合作用产生抑制。
To provide some evidence for the application of Cu fertilizer in Paeonia lactiflora cultivation,foliage-spraying experiment with different Cu concentrations of 0 mg/L,100 mg/L,200 mg/L,400 mg/L,600 mg/L and 800 mg/L were carried out.The photosynthetic pigment contents,photosynthetic characteristics as well as chlorophyll fluorescence parameters of Paeonia lactiflora were determined and analyzed.The results showed that there were significant differences among different Cu concentration treatments.The light compensation point(LCP) of different treatments were 6-12 μmol/(m^2.s,the light saturation point(LSP) were 500-1 000 μmol/(m^2.s,the CO2 compensation point were 60-90 μmol/mol,and the CO2 saturation point were 1 000-1 600 μmol/mol.The 400 mg/L Cu treatment had higher light saturation point(LSP),CO2 saturation point,apparent quantum yield(AQY) and carboxylation efficiency(CE).The diurnal variations of photosynthesis of Paeonia lactiflora treated by different Cu concentrations showed a single peak curve.All treatments had the highest Pn at 9∶00 am and the lowest Pn at 15∶00 pm.The 200 mg/L and 400 mg/L Cu treatments had the highest Pn.When Cu concentration was 800 mg/L,Fv/Fm and AQY were lower,and the photosynthesis of Paeonia lactiflora was inhibited.Foliar application of Cu fertilizer has a significant influence on photosynthetic efficiency of Paeonia lactiflora.In the range from 100 to 400 mg/L,photosynthetic efficiency increased with increasing Cu concentration,however,the over high concentrations would induce inhibition of the photosynthetic efficiency.From the experiment,it came to a conclusion that foliar application of 400 mg/L Cu could improve the photosynthetic efficiency of Paeonia lactiflora.