Molecular marker analysis and their correlation with phenotypic trait of Hibiscus varieties in southern Zhejiang

To resolve the issues of unclear parental origins and unstable offspring traits during Hibiscus syriacus L. breeding by farmers, the genetic variability analysis and correlation analysis on phenotypic traits and molecular makers were performed.

50 Hibiscus syriacus L. germplasms were used as experimental materials, with the data code method, the genetic variability analysis of ISSR and AFLP molecular makers were performed to trace the parentage of ‘local new variety’@@@. The correlations among 7 phenotypic indicators and their correlations with molecular markers were obtained by correlation analysis, and the phenotypic traits with strong genetic stability were selected to provide target phenotypes for the breeding of improved Hibiscus syriacus L.

The results showed that a total 62 polymorphism fragments and 59 polymorphic fragments of 50 germplasms are generated from of 7 pairs of ISSR primers. The polymorphism rate reaches 95.16%, the genetic similarity coefficients are 0.051 4-1.000 0. Simultaneously, a total 49 polymorphism fragments and 47 polymorphic fragments of 50 germplasms are generated from of 23 pairs of ISSR primers. The polymorphism rate reaches 95.92%, the genetic similarity coefficients are 0.000 0-1.000 0. By comparing the genetic similarity coefficients between ‘local new variety’@@@ and foreign varieties, parental origin tracing is successfully accomplished for four cultivars (No. 21、No. 22、No. 23、No. 24). It shows that there are the significantly different in 7 phenotypic traits. The mean coefficient of variation (CV) is 46.00, and the phenotypic diversity index (H) of 50 cultivars are 0.405-2.049. The results of correlation analysis show that the correlations of 4 phenotypic traits about petals type (PT), floral halo (FH), FR and seed shape (SS) are significant, and the correlations of 3 phenotypic traits about FC, leaf shape (LS) and leaf margin serration (LMS) are not significant. There are significance correlations between phenotypic traits and the polymorphism sites of molecular markers, among which PT, FH and FR possess more correlated polymorphism sites, all exceeding 15%. In contrast, FC, LS and LMS possess fewer correlated polymorphism sites, all below 5%. The correlation analyses indicate that this three traits, FC, LS and LMS, are not suitable as target phenotypes to avoid producing offspring with unstable trait expression during new cultivar breeding.

This study provides new research ideas and directions for the variety certification and improving the trait stability of ‘local new variety’@@@, obtained from the resource survey.