Comprehensive evaluation on major agronomic traits of pepper under cadmium stress based on membership function method
[Objective]The change law in major agronomic traits of pepper is explored under cadmium stress to provide the scientific basis for rapidly screening pepper germplasm resources with excellent cadmium tolerance.[Method]The effects of two cadmium concentrations(0.5 and 4.0 mg/kg)on plant height(PH),plant width(PW),stem diameter(SD),leaf color(LC),number of fruits per plant(NF)and yield per plant(YPP)of 48 pepper varieties(lines)were investigated by a pot experiment and the cadmium tolerance of 48 pepper varieties(lines)was evaluated by using membership function method and clustering analysis.[Result]The average values of PH,PW,SD,LC,NF and YPP of 48 pepper varieties(lines)under low and high cadmium concentrations were obviously lower than that of CK(44.87 cm,38.87 cm,5.47 mm,3.15,29.25 and 209.43 g)and decreased by 5.06 cm/9.08 cm,6.45 cm/9.88 cm,0.97 mm/1.26 mm,0.98/1.48,6.23/1142,and 44.60 g/81.37 g compared with CK respectively.Leaf color was the most sensitive to cadmium stress among six agronomic traits.The variable coefficients of PH,PW,SD,LC,NF and YPP of 48 pepper varieties(lines)under low and high cadmium concentrations were 15.92％ /17.38％ ,16.59％ /17.87％ ,9.78％ /13.54％ ,35.94％ /39.52％ ,28.93％ /29.61％ and 48.21％ /52.55％ respectively and higher than that of CK.The variable coefficients increased with increase of cadmium concentration.48 pepper varieties(lines)were di-vided into five groups of high tolerance,tolerance,moderate tolerance,sensitivity,and high sensitivity according to weighted membership func-tion D values under different cadmium concentrations based on clustering analysis.There were significant or highly significant positive correla-tions between membership function values of PH,PW,SD,LC,NF and YPP,which indicated that there were great differences in cadmium tol-erance among 48 pepper varieties(lines).There were 6 varieties with high cadmium tolerance[H13(Chengdu Erjingtiao),Z15(new gener-ation),Z9(Fengming pepper),SX(Shaanxi line pepper),H31(purple pepper)and YZ12(inbred line)],7 varieties with cadmium toler-ance,16 varieties with moderate cadmium tolerance,13 varieties with sensitive to cadmium and 6 varieties with high sensitive to cadmium a-mong 48 tested pepper varieties(lines)respectively.[Conclusion]The cadmium tolerance of pepper varieties can be rapidly evaluated by surveying apparent agronomic traits to provide a reference for practical production of pepper and speed up the selection process of pepper vari-eties with cadmium tolerance.
万方数据
维普
