酸性环境对镉胁迫下水稻幼苗生长的影响  

Effects of Acid Environment on Rice Seedling Growth under Cadmium Stress

作　　者：任新宇 罗晟 魏宏宇 程新[1,2] REN Xinyu;SLUO Sheng;WEI Hongyu;CHENG Xin(Institute of Applied Microbiology,Jiangxi Agricultural University,Nanchang 330045,China;College of Bioscience and Bioengineering,Jiangxi Agricultural University,Nanchang 330045,China)

机构地区：[1]江西农业大学应用微生物研究所,江西南昌330045 [2]江西农业大学生物科学与工程学院,江西南昌330045

出　　处：《河南农业科学》2022年第4期39-47,共9页Journal of Henan Agricultural Sciences

基　　金：江西省自然科学基金项目(20202BABL205019);江西省教育厅科技计划项目(GJJ180211)。

摘　　要：采用水培试验研究酸性环境(pH值分别为5.0、6.0、6.8)对镉(Cd,0、0.3、0.6 mg/L)胁迫条件下水稻幼苗生长的影响,以期明确酸性环境与Cd胁迫的互作效应,并为农作物的安全生产提供理论依据。结果表明,Cd胁迫抑制水稻幼苗地上部的生长,而一定程度的弱酸性环境有利于Cd胁迫条件下水稻幼苗地上部的生长,在pH值6.0时水稻幼苗地上部的生长状况最好,叶片叶绿素和类胡萝卜素含量最高;但当pH值下降至5.0时,水稻幼苗地上部的生长受到抑制,叶片叶绿素和类胡萝卜素含量最低,说明酸性环境加剧了Cd胁迫对水稻幼苗地上部生长的抑制作用。当Cd质量浓度≤0.3 mg/L时,水稻幼苗根系发育(总长、表面积、直径、总体积、根尖数)在pH值6.0时最好,在pH值5.0时发育最差,根系POD活性及MDA含量总体均随着pH值的降低而升高。同时伊文斯蓝染色试验及活性氧检测试验结果也表明,在Cd质量浓度为0.6 mg/L时,水稻幼苗根系的损伤程度随着pH值的降低而增强。综上可知,当pH值<6.0时,酸性环境会加剧Cd对水稻幼苗的毒害效应。In order to clarify the interaction between acid environment and cadmium(Cd)stress and provide theoretical basis for the safe production of crops,the effects of acid environment(pH values were5.0,6.0,6.8,respectively)on the growth of rice seedling under Cd(0,0.3,0.6 mg/L)stress were studied by hydroponic experiment.The results showed that Cd stress had inhibitory effect on the growth of rice seedling shoot,but weak acid environment favored the growth of rice seedling shoot under Cd stress,when the pH value was 6.0,the growth of rice seedling shoot,and the contents of chlorophyll and carotenoid in leaves were the highest.However,when the pH value decreased to 5.0,the growth of rice seedling shoot was strongly inhibited,and the contents of chlorophyll and carotenoid in leaves were the lowest,indicating that the acid environment intensified the inhibition of Cd stress on growth of rice seedling shoot.When the Cd concentration was below 0.3 mg/L,the root growth of rice seedling(total length,surface area,diameter,total volume and root tip number)was the best at pH value of 6.0,the worst at pH value of 5.0,and malondialdehyde(MDA)content and peroxidase(POD)activity generally increased with the decrease of pH value.Also,the results of evans blue staining test and reactive oxygen species(ROS)detection test showed that the damage of rice seedling root was strengthened with the decrease of pH value under 0.6 mg/L Cd stress.In conclusion,the acidic environment can aggravate the toxic effect of Cd on rice seedling when the pH value is less than 6.0.

关 键 词：酸性环境 镉胁迫 水稻 生长 根系损伤 

分 类 号：S511[农业科学—作物学]