Growth Response and Tolerance Evaluation of 32 Spinach Varieties to Cadmium Stress
Cadmium(Cd)is a highly toxic heavy metal element.To identify Cd-tolerant spinach varieties and screen related identification indexes,and provide a theoretical basis for the selection and breeding of Cd-tolerant varieties,in the present study,we conducted a hydroponic experiment using 32 spinach varieties in China.The spinach was exposed to Cd stress(Cd concentration of 50 μmol/L)for 20 days,while the other group of plants was treated as a control(Cd concentration of 0 μmol/L).After the plants reached maturity,we measured the agronomic traits and Cd content.The integrated Cd tolerance of each spinach variety was evaluated by principal component analysis,affiliation function analysis,and correlation analysis.The results showed that plant height,root length,underground fresh weight,aboveground fresh weight,aboveground Cd content,underground Cd content and translocation coefficient of the participating varieties under Cd stress conditions were significantly different from the control.Under Cd stress,the growth and biomass accumulation of spinach were inhibited,and the indicators of each trait decreased significantly.The order of average reduction of each agronomic index was aboveground fresh weight>plant height>underground fresh weight>root length.The principal component analysis of Cd stress tolerance index of the seven indexes was performed,and three principal components were selected,with a cumulative variance contribution of 81.552%;The composite evaluation value(D value)showed highly significant positive correlations(P<0.01)with plant height,underground fresh weight,aboveground fresh weight,aboveground Cd content,and translocation coefficient,which can be used as the preferred indexes for the evaluation of Cd tolerance in spinach.Based on the principal component analysis,we classified the 32 spinach varieties into three categories:Cd-tolerant,moderate,and Cd-sensitive varieties.Among the varieties tested,Jin'ge and Micro orchid exhibited strong Cd tolerance,while Desai 176 was found to be Cd-sensitive.
SpinachCd toleranceCd uptakeAffiliation function methodPrincipal component analysisComprehensive evaluation
万方数据
维普
