铁胁迫对三种柑橘砧木的生长、生理特性及铁分布的影响

Effects of iron stress on growth, physiological character and iron distribution of the three citrus rootstocks

关键词:  铁胁迫  柑橘砧木  生长  生理特性  铁分布

Key words:  iron stress  citrus rootstock  growth  physiological character  iron distribution

摘要:

以枳壳、酸橙和红橘三种柑橘砧木实生苗为材料,采用溶液培养法研究了铁胁迫对其生长、生理特性及铁分布的影响。结果表明:缺铁胁迫(0 μmol·L^-1)时,三种柑橘砧木的生长指标及叶片叶绿素含量均显著低于低铁(5 μmol·L^-1)和适量铁(50 μmol·L^-1)处理; 三者叶片和根系的POD、CAT活性显著降低,SOD活性变化复杂,根系脯氨酸含量显著上升。缺铁和低铁处理时,三者根系铁含量值相当,均显著低于对应适量铁处理; 随着铁处理浓度的升高,三者铁的叶/根、茎/根转运系数均逐渐降低,而叶/茎转运系数无明显差异。

Abstract:

The three citrus rootstock seedlings such as trifoliate orange,sour orange and red tangerine were taken as experimental material,the effects of iron stress on the growth,physiological character and iron distribution of the three rootstocks were investigated with hydroponics. The results showed that the growth index and chlorophyll concentrations in leaves of the three rootstocks were significantly lower in the iron deficiency(0 μmol·L^-1)than in the treatments of low iron(5 μmol·L^-1)and optimal iron(50 μmol·L^-1),the activities of POD,CAT in leaves and roots decreased and the proline content in roots increased significantly under the iron deficiency treatment,and the activities of SOD in leaves and roots of the three rootstocks changed irregularly. Under the treatments of iron deficiency and low iron,iron contents in roots showed no difference among the three rootstocks,but were significantly lower than those of optimal iron treatment,respectively. The leaf/root and the stem/root of Fe translocation coefficient in the three rootstocks decreased with increasing supply of Fe,whereas no significant difference was found in the leaf/stem of Fe translocation coefficient.