In order to clarify the genetic characteristics of main ornamental traits and cold resistance of Forsythia， the F1 hybrid obtained from Forsythia intermedia ‘Lynwood’×F. mandschurica was taken as material. The 12 phenotypic traits such as corolla diameter， corolla lobe length and cold resistance were measured， and correlation analysis and mixed genetic model analysis of these traits were carried out. The results showed that F1 population varies significantly and the new phenotypic traits precede parents. Except for corolla lobe length， corolla lobe width and leaf length， the coefficient of variation of other phenotypic traits was more than 15% respectively， reaching a medium level or above. There was a certain correlation between the phenotypic traits， and the cold resistance was significantly positively correlated with flower density， but was significantly negatively correlated with corolla diameter and crown width of the plant. Mixed genetic model analysis revealed that corolla lobe length， corolla lobe width， length-width ratio of corolla lobe， leaf length， leaf width， length-width ratio of leaf， shoot length， cold resistance were controlled by minor-polygene respectively； corolla diameter and crown width were controlled by a pair of additive-dominant major genes respectively； flower density was controlled by two pairs of additive-dominant major genes； plant height was controlled by two pairs of equally additive-dominant major genes. The heritability of major-gene for corolla diameter， crown width， flower density and plant height were 76.05%， 60.3%， 72.22% and 64.75%， respectively. This research results would provide a basis for target breeding of new varieties of Forsythia with excellent comprehensive traits.
%U https://bbr.nefu.edu.cn/EN/10.7525/j.issn.1673-5102.2021.03.004