Biotechnology Assists Lily Variety Improvement
China is the natural distribution center of the genus Lilium. On this land, there are 47 species and 18 varieties of native lilies, which hold a very important position in the improvement of lily varieties worldwide. However, currently less than half of the original lily species are used in breeding, and there are still many original lily species with special superior traits that urgently need further development and utilization. Researchers at China's scientific research and teaching institutions have conducted a detailed analysis and study of the progress in lily variety improvement and biotechnology research in China.
China's lilies have obvious advantages: Lilium dauricum, Lilium distichum, and others have upright, upward-facing flowers and tall plants, making them suitable for breeding cut flower varieties; Lilium souliei, Lilium nanum, Lilium amoenum, Lilium lophophorum, Lilium matangense, Lilium rosthornii, and Lilium sempervivoideum have small plants, making them suitable for breeding miniature potted varieties; Lilium henryi, Lilium dauricum, Lilium pumilum, and Lilium regale are important parents for disease-resistant breeding. Some lilies can be used for cold-resistant breeding, and some can be used for heat-resistant breeding. These rich and colorful original species are important parents for improving lily plant architecture, resistance, and other traits through cross-breeding. Biotechnology in lily variety improvement is mainly applied in in vitro preservation of germplasm resources, in vitro embryo culture to overcome cross-incompatibility in distant hybridization, anther culture and haploid breeding, targeted trait modification using transgenic technology, and rapid propagation of superior varieties. The combination of biotechnology and conventional breeding gives lily breeding work broad prospects.
Among the newly bred lily varieties, the vast majority adopt the method of cross-breeding, and a considerable portion of these are distant hybridization, with gratifying achievements made in the field of breeding. Flower color, fragrance, and flower shape are the main goals of flower breeding. Although lilies have diverse flower colors, they lack bright red and blue-purple. The upright trumpet shape of lily flowers is the main goal of flower shape improvement. Increasing the fragrance of Asiatic lilies and reducing the fragrance of Oriental lilies are the goals of fragrance breeding. In terms of flowering period, the main focus is on breeding early-flowering and late-flowering varieties to extend the flowering period and ornamental period. In terms of plant architecture, cut flower varieties require tall plants, while miniature potted varieties require short plants. Stress resistance is also an important breeding goal.
In addition, factors such as vase life, absence of pollen, and reproductive capacity must also be considered. Experts introduce that by transferring disease-resistance-related genes into cultivated varieties, plants with both excellent ornamental value and strong resistance can be screened out. For ethylene-sensitive species and varieties, ethylene metabolism can be controlled through genetic engineering to extend vase life. The absence of pollen is related to male sterility, and introducing male sterility genes is expected to solve the problem of lily pollen contamination. To achieve rapid propagation of lily hybrid seedlings, tissue culture technology will have great potential.