Abstract:

To investigate the effects of different parents in interspecific hybridization of the genus Fraxinus on hybrid F₁ seeds, a total of 36 interspecific hybridization combinations of the genus Fraxinus were designed, and F₁ seeds from various hybrid combinations were collected. Statistical analysis of characteristic data such as thousand seed weight, wing length, wing width, and wing length/width of seeds was conducted. SPSS 24.0 software was used to perform variance analysis on the data, comparing the differences between inter species hybrids and intra species hybrids, as well as the effects of different genotypes of maternal and paternal parents on hybrid species. The results showed that there were significant differences in the four indicators of F₁ seeds between interspecific hybridization and intraspecific hybridization when F. pennsylvanica was used as the maternal parent and different species of Fraxinus male parent. The variation range between different combinations of interspecific hybridization was large. However, when using F. velutina as the maternal parent and different species of Fraxinus male parent, there was no significant overall difference in seed traits between interspecific hybridization and intraspecific hybridization. Four genotypes of F. velutina were hybridized with the female parent of F. mandshurica, resulting in significant variations in seed traits in the F₁ generation. Five genotypes of F. velutina were hybridized with the male parent of F. pennsylvanica, resulting in significant differences in thousand seed weight traits in the F₁ generation; The F₁ seed trait variation obtained by crossing the male parent of F. mandshurica with and the female parent of F. velutina was superior to that of the hybrid combination with F. pennsylvanica as the female parent. The results showed that the F₁ hybrid seeds in the interspecific hybrid of the genus Fraxinus had abundant genetic variation. Overall, it is believed that the variation of hybrid seeds with F. velutina as the maternal parent is higher than that as the paternal parent. Different genotypes of F. mandshurica as the paternal parent have no significant effect on the seed traits of F₁ generation. The study provides a reference for the selection of parents for interspecific hybridization in the genus Fraxinus, further improving the efficiency of Fraxinus.

Key words: Fraxinus, interspecific hybridization, F₁ generation, parent selection, phenotypic traits, seed traits, genetic variation