铜胁迫对海州香薷和紫花香薷根系形态及铜富集的影响

Influence of Cu Toxcity on Root Morphology and Cu Accumulation of Elsholtzia splendens and Elsholtzia argyi

通过水培试验,研究了在不同Cu浓度处理条件下海州香薷和紫花香薷根系形态和植物各器官铜含量、累积量间的差异。结果表明:低浓度Cu处理(<50μmol/L)对海州香薷的生长有一定的促进作用,植株干重、根系长度、根系表面积、根体积和侧根均略有升高。但随着Cu浓度(100～500μmol/L)增加,表现出一定的负效应,海州香薷在500μmol/LCu处理时植株干重、根系长度、根系表面积、根体积和侧根明显受到抑制,与对照相比差异达显著或者极显著水平。紫花香薷在50μmol/LCu处理时根系生长就受到严重抑制,而当浓度再增加时,根系形态的各项指标则无明显变化。海州香薷地上部铜含量明显高于紫花香薷。

Elsholtzia splendens and Elsholtzia argyi are both dominant plants growing in Cu mining area. Solution culture experiments were conducted to study the effect of difference copper levels on root morphology and copper accumulation in Elsholtzia splendens and Elsholtzia argyi. The results showed that under low Cu level(<50μmol/L), the growth of Elsholtzia splendens was improved, with slight increase in dry weight, root length, root surface-area and root volume. However, with increasing of Cu supply levels (100～500μmol/L), an obvious decrease was found in dry weight, root length, root surface-area and root volume for Elsholtzia splendens, with the differences being at significant and very significant levels (P<0.05 or 0.01), as compared with the control. In contrast, the growth of Elsholtzia argyi was inhibited severely even at low Cu level(<50μmol/L), and all the parameters of root morphology varied slightly with increasing external Cu level. Copper content in shoot of Elsholtzia splendens was much higher than Elsholtzia argyi, which suggested that Elsholtzia splendens has better ability to transfer Cu from root to shoot.