Cu~(2+)胁迫对糯和非糯玉米生长发育的影响

选择糯、非糯玉米种子,在相同的Cu2+浓度梯度下胁迫培养。结果表明:低浓度的铜具有促进玉米种子萌发的作用,50mg/LCu2+处理浓度下二者的发芽势和发芽率均达到高峰,随着Cu2+处理浓度的加大,2种玉米的发芽率和发芽势呈下降趋势;20mg/LCu2+处理浓度对2种玉米的根长、株高、地上部分和根的干重具有显著的抑制作用,随着处理浓度的增加,这种抑制效应更为明显;随着处理浓度的增加叶绿素a、b和总叶绿素含量呈下降趋势,而叶绿素a/b的比值却升高。研究发现:在发育早期,糯玉米对Cu2+的敏感性强于非糯玉米,非糯玉米对Cu2+胁迫具有较强的耐受力和适应性。

Effects of Cu2+ Stress on Growth and Development of Glutinous and Non-glutinous Maize

The seeds of both glutinous and non-glutinous maizes were cultured under Cu2+stresses with an identical gradient of Cu2+ concentration.The results showed that the lower Cu2+ concentration could promote the seed germination of maize,and the treatment with 50mg/L Cu2+ had the highest germination potential and germination rates for both maizes,but with the increase of Cu2+ concentration,the two characters presented a decreased trend.20mg/L Cu2+ concentration could significantly inhibit the root length,plant height,dry matter weight(DW)of leaves and roots,and chlorophyll content.With the increase of Cu2+ concentration,the chlorophyll a,b and content dropped,but the a/b rate increased.Compared with glutinous maize,non-glutinous maize had narrow changing amplitudes for all indexes measured,demonstrating that it had stronger adaptation to Cu2+ stress than the former.