Research Of Cross-breeding Of Lilium

Lily belongs to Lilum of Liliaccae, which is widely used in garden, potted flower and cut flower especially. China is the main country in producing cut flowers of Lily. However, all the varieties and 90% bulbs depend on importation and Lily is easy to catch virus and disease, which block the development of cut flower of Lily in China. Breeding for resistance against disease and novel varieties of Lily.,the research chose wild species of Lily which have the ability of resistance against disease as male parent for the combination of Asiatic hybrids×wild Lily and chose the complemantary pairs Oriental hybrids and Asiatic hybrids as parents to cross in vitro. The research contained the following aspects: (1)The effects of different pollination methods like'mentor'and'pioneer'pollination, cut-style pollination , pollination with Ca2+ in pollen germination liquor on fruitset and seedset for cross-breeding. (2) The effects of the method which integrated in vitro pollination, ovary slice culture and ovule culture for overcoming the barriers of Oriental hybrids×Asiatic hybrids.(3)Obtaining the best media for bullet propagation of the plantlets from the cross combinations.(4)Identification by ISSR proved that'Navona'×Lilium dauricum was true hybrids.Results of the research are as following:(1)9 combinations were tested,1051 flowers were crossed, 6004 seeds were obtained, 542 young seedlings were planted in Asiatic hybrids×wild Lily. 7 combinations were tested, 358 pairs of flowers were grafted, 1416 ovules were obtained, 3 young seedlings were planted in Oriental hybrids×Asiatic hybrids(2)The methods of'mixture','mentor'and'pioneer'pollination using for overcoming lilium cross barriers of the'Pollyanna'×lilium leichtlinii var. maximowiczii were studied.The result showed that the irradiation pollen of 10Gy and 100Gy lost pollination abilities completely and a small amount of seeds were produced by the application of 10Gy and 100Gy mentor pollen. By using the normal stigma pollination, a number of fruits and plump seeds were produced, which indicated the cross'Cordelia'×lilium dauricum was a compatible cross. By applying the irradiation pollen's assisting pollination methods (1000Gy or 2500Gy mentor pollen), fruitset and seedset were raised obviously,. The use of the cross chemical's assisting pollination exhibited raised the fruitset and seedset to some extent. The application of the cut-style pollination deduced the fruitset and seedset .(3)Ca2+ is able to promote the pollen energy and pollen tube length, and also can raised the seedset, the most suitable concentration of Ca2+ is 4mol/L.Meanwhile, normal stigma pollination with pollen germination liquor is better than cut-style pollination with pollen germination liquor.(4)The method which integrated in vitro pollination, ovary slice culture and ovule culture was proved that can overcome the barriers of Oriental hybrids×Asiatic hybrids to some extent. Ovary slice development appeared to be positively affected by the presence of young anthers in 7 days after pollination.The number of hybrid plantlets was very limited, the reasons may as following: the genetic distance of the parents is not close, contamination hazards and ovule culture condition was not suitable, which need refinement.(5) The research demonstrated that the best media for bullet propagation of the plantlets from the cross combinations of'Cordelia'×Lilium dauricum and'Navona'×Lilium dauricum is: MS+NAA0.1mg/L + BA1.0mg/L.(6)15 kinds of ISSR primes were used, which showed the hybrid bands included both parental bands. The hybrid was true progeny of their parents.