摘要
为探究不同浓度锌(Zn)对镉(Cd)胁迫条件下玉米幼苗生长及根系构型分级的影响,通过水培试验,以玉米品种郑单958为试验材料,研究Cd胁迫条件下(50μmol·L^(-1)),外源施加不同浓度Zn(0、10、25、50、100、200和400μmol·L^(-1))对玉米幼苗生长、根系构型及其分级特征、Cd含量及根系Cd吸收能力、光合系统的影响,并通过主成分分析和隶属函数法进行综合评价.结果表明,50μmol·L^(-1)Cd胁迫对玉米幼苗具有明显的毒害作用,使叶绿素含量和光合参数显著降低,主根长、株高、生物量、根分枝数和根尖数,包括Ⅰ~Ⅲ级径级区间的根长、根表面积及Ⅰ~Ⅱ级径级区间的根体积显著下降,阻碍了玉米幼苗的正常生长发育.施用100μmol·L^(-1)和200μmol·L^(-1)Zn与不施Zn相比,降低了玉米幼苗对Cd的吸收,显著降低了Cd含量和Cd吸收效率,缓解了对玉米幼苗的毒害作用,使地上地下部鲜重、地上部干重、地上地下部耐受指数和根分枝数均显著升高;显著增强了玉米幼苗的光合作用,促使幼苗光合速率和总叶绿素含量显著升高;Ⅰ级径级区间的RL、Ⅰ~Ⅱ级径级区间的SA和RV在100μmol·L^(-1)Zn时达到最大,Ⅲ级径级区间的RL、SA和RV在200μmol·L^(-1)Zn时达到最大,均显著高于不施Zn处理;玉米幼苗生长耐受性综合评价表明,100μmol·L^(-1)和200μmol·L^(-1)Zn缓解Cd毒害作用效果较好.综合分析可知,施加适宜浓度的Zn可以降低玉米幼苗植株内Cd含量、根系Cd吸收能力及Cd吸收效率,提高玉米幼苗生物量的积累,减轻Cd毒害对根系构型的影响,减少对光合系统的影响,提高玉米幼苗对Cd的耐受性.
To explore the effects of different concentrations of zinc(Zn)on the growth and root architecture classification of maize seedlings under cadmium(Cd)stress,a hydroponic experiment was conducted to study the effects of different concentrations of Zn(0,10,25,50,100,200,and 400μmol·L^(-1))on the growth,root architecture and classification characteristics,Cd content,root Cd uptake capacity,and photosynthetic system of maize seedlings under Cd stress(50μmol·L^(-1))by using Zhengdan 958 as the experimental material.Principal component analysis and the membership function method were used for comprehensive evaluation.The results showed that the 50μmol·L^(-1) Cd stress had a significant toxic effect on maize seedlings,which significantly reduced chlorophyll content and photosynthetic parameters.The main root length,plant height,biomass,root forks,and root tips,including the root length and root surface area of the grade Ⅰ-Ⅲ diameter range and the root volume of the grade Ⅰ-Ⅱ diameter range,decreased significantly,which hindered the normal growth and development of maize seedlings.Compared with that under no Zn application,100μmol·L^(-1) and 200μmol·L^(-1) Zn application reduced the uptake of Cd by maize seedlings,significantly reduced the Cd content in shoots and roots and the Cd uptake efficiency.The toxic effect on maize seedlings was alleviated,and the fresh weight,dry weight,tolerance index,and root forks of shoots and roots were significantly increased.The photosynthesis of maize seedlings was significantly enhanced,and the photosynthetic rate and the total chlorophyll content was significantly increased.The RL,SA,and RV in the Ⅰ-Ⅱ diameter range reached the maximum at 100μmol·L^(-1) Zn,and the RL,SA,and RV in the Ⅲ diameter range reached the maximum at 200μmol·L^(-1) Zn,which were significantly higher than those without Zn treatment.The comprehensive evaluation of the growth tolerance of maize seedlings showed that 100μmol·L^(-1) and 200μmol·L^(-1) Zn had better effects on alleviatin
作者
张辉红
魏畅
柳海涛
张静静
刘芳
赵颖
张雪海
李鸽子
姜瑛
ZHANG Hui-hong;WEI Chang;LIU Hai-tao;ZHANG Jing-jing;LIU Fang;ZHAO Ying;ZHANG Xue-hai;LI Ge-zi;JIANG Ying(College of Resources and Environment,Henan Agricultural University,Zhengzhou 450046,China;State Key Laboratory of Wheat and Maize Crop Science,College of Agronomy,Henan Agricultural University,Zhengzhou 450046,China;National Engineering Research Center for Wheat,Henan Agricultural University,Zhengzhou 450046,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2024年第2期1128-1140,共13页
Environmental Science
基金
国家重点研发计划重点专项(2021YFD1700904)
河南省农业农村厅重点项目(30801910)
河南省留学人员科研择优资助项目(30602340)
河南农业大学大学生创新训练计划项目(2022DC158)。
关键词
玉米
镉(CD)
锌(Zn)
生理参数
根系构型分级
maize
cadmium(Cd)
zinc(Zn)
physiological parameters
root architecture classification
