Interspecific Crossing between Lilium hansonii Leichtlin and L. brownii var. colchesteri for the Breeding of New Lily Cultivars

Abstract

This study aimed to generate interspecific hybrids between two remote lily species, L. hansonii Leichtlin and L. brownii var. colchesteri. Reciprocal crosses were performed by conventional and cut-style pollination methods, but viable seeds were only obtained when L. hansonii was used as the female parent, indicating that unilateral incompatibility exists between the two species. In the case of immature seeds, embryos with 2~3 mm were carefully removed from testa for further in vitro culture, and they grew as normal plants. A total of 343 progenies was obtained from the crosses, and hybridity of the progenies were examined using the L9 marker, simple sequence repeat (SSR) marker, at the seedling stage and 92 were confirmed as F1 hybrids. Ploidy level of 76 F1 hybrid was examined and confirmed as diploid. F1 hybrids exhibited intermediate morphologies of the parent in outer tepal and leaf length, but flower shape and color were similar to those of L. hansonii. On the other hand, F1 hybrid plants showed increased flower spots, flower size, and bud numbers, which could be important signatures of the F1 hybrid. This study reports the first attempt to generate an interspecific hybrid between the two species, and therefore, our results from this study would be very informative for future lily breeding.