Comprehensive evaluation of salt tolerance in ginger at seedling stage and expression pattern of aquaporin protein
[Objective]To investigate the effects of salt stress on morphological changes and physiological indexes of ginger at seedling stage,establish a salt-tolerant evaluation system for ginger,explore salt-tolerant germplasm resources,which could provide theoretical reference for the selection and breeding of salt-tolerant varieties of ginger.[Method]The main plant varieties from 5 major ginger producing areas in China were used as experimental materials,and 2 treatments,control(CK)and salt stress(NaCl),were set up.Principal component analysis was used to integrate the physiological and biochemical indexes and other individual indexes into 3 comprehensive indexes,and combined with the method of the membership function to carry out a comprehensive evaluation of salt tolerance,and to analyze the expression of the aqua-porin protein(AQP)gene in the salt-tolerant varieties and the sensitive varieties.[Result]The increase in plant height,stem thickness,number of leaf,root vigour,leaf water potential and leaf osmotic potential decreased in all ginger varie-ties under salt stress.Hydrogen peroxide(H2O2)content,malondialdehyde(MDA)content and peroxidase(POD)activity of leaves were increased.Superoxide dismutase(SOD)activity was significantly increased in Guizhou ginger(P＜0.05,the same below)but decreased in the other 4 varieties.Catalase(CAT)activity was decreased in Shandong big ginger but elevated in the other 4 varieties.Phenylalanine deaminase(PAL)activity decreased in Shandong big ginger and Zhugen ginger,but increased in the other 3 varieties.Plant height,stem diameter and number of leaf were significantly and posi-tively correlated with the comprehensive evaluation value(D value).Leaf MDA content,H2O2 content,water potential and osmotic potential were negatively correlated with D values,root vigour was extremely significantly and positively correlated with D value(P＜0.01).The salt tolerance of ginger was ranked from the strongest to the weakest as Shandong big ginger,Guizhou yellow ginger,Fengtou ginger,Luoping small yellow ginger and Zhugen ginger.Expression pattern analysis of 8 AQP genes showed that 7 AQP genes were down-regulated in Shandong big ginger leaves and 4 AQP genes were down-regulated in roots after salt stress treatment;3 AQP genes were down-regulated in leaves and 6 AQP genes were down-regulated in roots of Zhugen ginger.[Conclusion]Salt tolerance evaluation of 5 ginger varieties at seed-ling stage indicates that Shandong big ginger has the strongest salt tolerance and Zhugen ginger has the weakest salt tole-rance.Plant height,stem diameter,number of leaf and root vigour can be the main reference indexes for screening ginger salt-tolerant varieties.
gingersalt toleranceaquaporin proteinevaluation of salt tolerance at seedling stagephysiological response
万方数据
维普
