Comprehensive evaluation of photosynthetic performance of oriental melon varieties(lines)and screening of high photosynthetic efficiency

KANG Liyun; WANG Huiying; LI Xiaohui; GAO Ningning; LI Hailun; CHANG Gaozheng; ZHAO Weixing

doi:10.16861/j.cnki.zggc.2025.0130

Abstract：Through comprehensively evaluating the photosynthetic performance of oriental melon varieties(lines),screen-ing for high-efficiency germplasm resources,and laying the foundation for high-efficiency breeding of oriental melon.This study used seedling stage plug substrate cultivation to measure the photosynthetic indicators and agronomic traits of 45 oriental melon varieties(lines).Principal component analysis,membership function analysis,and cluster analysis were used to comprehensively evaluate the photosynthetic performance of oriental melon varieties(lines),and suitable high-efficiency evaluation indicators and varieties were screened.The results showed that there were significant differ-ence in the variation amplitude of 15 traits among 45 oriental melon varieties(lines),ranging from 10.32％to 54.75％.Among them,five traits,such as net photosynthetic rate(Pn),stomatal conductance(G,),water use efficiency(WUE),fresh plant mass,and dry plant mass,had large variations,and the coefficient of variation of all these traits was greater than 30％.Through principal component analysis,five principal components were extracted,and their cumulative contri-bution rate reached 84.915％.Pn,plant fresh MAmass,plant dry mass,root volume,root fresh mass,root dry mass,Gs,transpiration rate(T),vapor pressure difference(VPD),WUE,relative chlorophyll content(SPAD value),and leaf area were screened out as evaluation indexes for the high photosynthetic efficiency ability of oriental melon.Through cluster analysis of the comprehensive photosynthetic efficiency evaluation(D)values,45 oriental melon varieties(lines)were di-vided into four categories:High photosynthetic efficiency type,sub-high photosynthetic efficiency type,medium-high photosynthetic efficiency type,and low photosynthetic efficiency type.Twelve varieties(lines)with high photosynthetic efficiency,such as Boniu,Huangzi 168,TS-16,15-171,TS-13,15-146,TS-14,A69,TS-9,TS-6,TS-12,and 15-142,were preliminarily screened out,which can be used as germplasm of oriental melon and high photosynthetic efficiency suitable for breeding.