钙、硅对铝胁迫下荞麦光合生理的影响

采用营养液培养法,研究了钙、硅对荞麦根长、光合作用和叶绿素荧光的影响。结果表明,15 d时0.5 mmol/L和5 mmol/L Al3 处理降低了荞麦根长、叶绿素含量、净光合速率(Pn)、气孔导度(Ci),对叶绿素荧光Fv/Fm、Fv/Fo的影响不大,30 d后以上伤害均加重。配施钙或硅的处理,能促进根的伸长和提高叶绿素含量,并使叶片的Pn、Ci保持在较高的水平,施硅能明显提高荞麦叶片的叶绿素荧光Fv/Fm、Fv/F,而钙的影响不大。硅对铝胁迫的缓解效果好于钙。

Effect of Calcium and Silicon on Photosynthetic Physiology of Buckwheat under Aluminum Stress

A solution culture was conducted to study the effect of calcium and silicon on root length,photosynthesis and chlorophyll fluorescence in leaves of buckwheat under aluminum stress.Exposure to 0.5 mmol/L and 5 mmol/L Al3 for 15 d inhibited root growth and decreased chlorophyll contents,Pn and Ci,but had no significant difference to Fv/Fm and Fv/Fo.All the parameters aggravated after 30 d.Application of calcium or silicon ameliorated the toxic effects of Al3 on root growth and chlorophyll contents,and caused an increase in Pn and Ci.The addition of silicon to the 0.5 mmol/L and 5 mmol/L Al3 culture increased chlorophyll fluorescence,but changes were not observed in calcium.This suggested that the ameliorating effect of silicon on aluminum toxicity was better than that of calcium.