Identification and Fusarium wilt resistance evaluation of distant hybrid offspring of Lilium brownii var. viridulum

During the cultivation process of Lilium brownii var. viridulum, it is easy to be infected with wilt disease, while some varieties of ornamental lilies have strong resistance to wilt disease. The study aimed to create hybrids with improved resistance to wilt disease by crossbreeding Lilium brownii var. viridulum with various ornamental lily varieties. Disease-resistant ornamental lily cultivars were specifically chosen for reciprocal crosses with Lilium brownii var. viridulum. The authenticity of the hybrids was confirmed through SSR molecular markers, and the resistance of the hybrid offspring to wilt disease was subsequently assessed. The results were as follows:(1)Lilium Asiatic hybrids such as ‘Black stone' had strong resistance to Fusarium wilt, while Lilium brownii var. viridulum and ‘Pink planet' had the weakest resistance to Fusarium wilt.(2)A total of 28 capsules were obtained from the orthogonal combination using Lilium brownii var. viridulum as the maternal parent, and 3 Lilium brownii var. viridulum × ‘Black stone' hybrid seedlings were finally obtained. The cross combination of Lilium brownii var. viridulum as the male parent obtained a total of 74 capsules, and ultimately obtained a hybrid seedling of ‘Strawberry event' × Lilium brownii var. viridulum.(3)SSR molecular marker identification results showed that 3 hybrid seedlings of Lilium brownii var. viridulum × ‘Black stone' were real hybrids, while 1 hybrid seedlings of ‘Strawberry event' × Lilium brownii var. viridulum was a false hybrid.(4)The 3 Lilium brownii var. viridulum × ‘Black stone' hybrid seedlings obtained had moderate resistance to Fusarium wilt. This study provides a reference for the distant hybridization of Lilium brownii var. viridulum and ornamental lilies, and proves that Lilium brownii var. viridulum hybrids with Fusarium wilt resistance can be obtained through hybridization. This study provides technical guidance for the distant hybridization of Lilium brownii var. viridulum with ornamental lily varieties, laying the groundwork for the breeding of new lily varieties with enhanced resistance to wilt disease in the future.