外源蔗糖、Vc对铬诱导的拟南芥主根生长抑制和过氧化物积累的缓解作用

Exogenous Sucrose,Vitamin C Protects Arabidopsis from Chromic-induced Root Growth Inhibition which is Likely Mediated by Hydrogen Peroxide Production

通过水培实验研究重金属铬胁迫下拟南芥主根生长和过氧化物积累情况,以及外源施加蔗糖和维生素C对毒害的缓解作用。结果发现随着铬浓度的升高,植物主根生长受到了明显的抑制,胎盘兰染色表明高剂量的铬造成了主根的根尖细胞的死亡。进一步DAB染色发现铬胁迫诱导植物根尖大量积累过氧化氢,而在胁迫培养基中加入蔗糖和维生素C都可显著改善植物根的生长、减低过氧化氢的积累,并减少铬诱导的根尖细胞的死亡。上述结果表明铬胁迫诱导的拟南芥主根生长的抑制很可能是由于根尖细胞过氧化物积累所致。

The effect of sucrose and Vc on H2O2 accumulation and root growth inhibition of Arabidopsis were investigated in hydroponics. We found that Cr inhibits root elongation with increasing concentrations of Cr. Meristematic regions and the elongation zones were greatly shortened, suggesting cell division and cell elongation are all affected. Plant roots died of Cr overdose. DAB staining analysis showed that hydrogen peroxide （H2O2） accumulated in root tips when the seedlings were treated with Cr. Furthermore, we found that inclusion of sucrose （Su） and vitamin C （Vc） can dramatically increase the tolerance of the seedlings to Cr treatment. Taken together, the results suggest that inhibition of root growth induced by Cr is likely mediated by ROS production.