铬胁迫对辣椒幼苗生长和生理生化特性的影响

Effect of Chromic Stress on Growth and Physiology of Pepper Seedlings

[目的]探讨铬胁迫对茄果类蔬菜的毒害机理。[方法]通过水培试验,研究0(对照)、5、10、20、50和100 mg/L的K2Cr2O7Cr溶液对辣椒幼苗生长和生理的影响。[结果]随着Cr6+浓度的升高,辣椒幼苗的生长受到了明显的抑制,株高、根部和地上部的鲜重、干重显著降低,根冠比(干重)呈升高趋势,叶绿素含量、叶绿素a/b值呈下降趋势,细胞膜透性大幅度增大,丙二醛(MDA)含量显著升高,超氧化物歧化酶(SOD)活性下降,过氧化物酶(POD)活性先上升后下降。Cr6+浓度与根部和地上部的干重、叶绿素a含量均呈极显著的负相关,与叶绿素b含量呈显著的负相关。[结论]辣椒幼苗对低浓度的Cr6+具有一定的抵抗作用。

[Objective] The purpose was to discuss the toxicity mechanism of chromic stress （Cr Stress） on solanaceous vegetable. [Method] Through water cultivation test, the effect on growth and physiology of pepper seedling by using 0 （CK）, 5, 10, 20, 50 and 100 mg/L of K2Cr2O7Cr solution was studied. [Result] The growth of pepper seedling was inhibited obviously with the increasing of concentration of Cr^6＋ , the fresh and dry weight of plant height, root and aerial part were decreased significantly, the root-shoot ratio （dry weight ） showed raising tendency and chlorophyll content and chlorophyll a/b value had dropping trend, the cell membrane permeability increased greatly, malondialdehyde （MDA） content increased remarkably, the activity of superoxile dismutase （SOD） reduced, peroxidase （POD） activity risen up first and then dropped down. Cr^6＋ concentration had a significant negative correlation with all the dry weight of root and aerial part and content of chlorophyll a, and also presented a obvious negative correlation with the content of chlorophyll b. [ Conclusion] Pepper seedling had a certain resistant function to Cr^6＋ with low concentration.