Studies On Rapid Propagation And Polyploid Breeding Of Cut Flower Lilies

Lily is one of perennial bulbous flowers, which belong to the liliaceae of lilium. Lilium is one of the famous flowers of the world. It is used as a cut flower, a potted flowering crop and a garden ornament, So people specially love it. It has very high values in commerce and ornament. Polyploid breeding is an important approach for improving the view quality and resistance of lily. In the study, there were ten trial materials, the systemic tissue culture for Sorbonne and Tiber was studied. Based on the culture medium screening on best of all, we try to mouse out broad-spectrum culture medium adapt to rest of eight breeds. Additionally, tetraploid germplasm has been obtained by the treatment of colchicines and oryzaline in order to obtain the valuable breeds. The research established the base for polyploid breeding of lily.The result showed: The explants were dipped in the scour 10 minutes and washen 30min by tap water, then sterilized 90 seconds by 75% alcohol and 13min by 0.1% HgCl₂, rinsed 4-6 times by sterilized water. The appropriate medium for inducing buds from explants was MS+1.0mg/L 6-BA +0.2mg/L NAA, induction rate was 100% and mean of buds was 5.0. The best of multiplication medium for Sorbonne was MS+1.0mg/L 6-BA+0.1mg/L NAA, multiplication coefficient reached 6.25, MS+0.5mg/L 6-BA+0.2mg/L NAA was used as multiplication medium for Tiber, multiplication coefficient reached 5.0. The best rooting medium for Sorbonne was 1/2MS+0.5mg/L IBA, l/2MS+0.2mg/L IBA for Tiber, the states of plantlets and roots were good, the induction rate was 100%, The surviving rate of plantlets was above 90% after transplanted to the ground.Inoculate Yelloween,Fangin,Aotali,Rousejizuo,Cordelia, Monte Negro, Pollyanna,L.rosthornill on appropriate medium of inducing buds,proliferation and rooting of Sorbonne and Tiber, The result showed: these eight breeds have induced buds on MS+1.0mg/L 6-BA+0.2mg/L NAA, Cordelia,Pollyanna,Rousejizuo have the highest sprout rate, then Aotali,Monte Negro,Fangin, the worst was L.rosthornill and Yelloween, but those sprout rates have 40%.so MS+1.0mg/L 6-BA+0.2mg/L NAA become broad-spectrum culture medium for inducing buds. MS+1.0mg/L 6-BA+0.1mg/L NAA was suitable to multiplication for Yelloween, Fangin, Aotali, Cordelia, multiplication coefficient reached 3.2, MS+0.5mg/L 6-BA+0.2mg/L NAA was suitable to multiplication for Rousejizuo,Monte Negro,Pollyanna,L.rosthornill, multiplication coefficient reached 2.3, MS+1.0mg/L 6-BA+0.1mg/L NAA, MS+0.5mg/L 6-BA+0.2mg/L NAA were the broad-spectrum culture medium of eight breeds for multiplication. The broad-spectrum culture medium of rooting for Yelloween,Fangin,Aotali,Rousejizuo,Cordelia, Pollyanna was l/2MS+0.2mg/L IBA, the roots grow well and easy survive after transplanted to the ground.The inducing polyploid of lily was carried out by colchicines and oryzaline. Two methods were used and compared. The tetraploid plantlets were obtained by immersing buds in various concentrations of colchicine and oryzaline solution, and inoculating buds in the mediums containing colchicine. The result indicated that the way of immersing buds on colchicine was better. It was the most effectively induced by immersing buds of Sorbonne in 0.05% colchicine solution for 20h, Tiber in 0.02% colchicine solution for 15h, which had the most tetraploid plantlets, inductive frequency was 13.3%. Buds of Sorbonne were incoculated in the medium contained 0.1% colchicine for 15 days, Tiber's incoculated in the medium contained 0.05% colchicine for 15 days, had the most tetraploid plantlets, the inductive frequency was 10.0% and 6.7%, It was the effectively induced by immersing buds of Sorbonne in 0.003% oryzaline solution for 9h, Tiber in 0.003% oryzaline solution for 6h, which had the most tetraploid plantlets, inductive frequency were 13.3% and 10.0%.The leaf, stoma, guard cell characteristics of tetraploids and diploids lily were compared. The result indicated that tetraploids leaves were thicker, but shorter and with lower leaf index. The thickness leaves of tetraploids Sorbonne and Tiber were 200% and 162.1% of those of the diploids respectively; the length of leaves of tetraploids were 82.8% and 75.8% of those of the diploids respectively. The tetraploids of Sorbonne and Tiber with fewer stoma densities which were 58.7% and 71.4% of those of the diploids respectively, with bigger guard cells. The guard cells' length of tetraploids Sorbonne and Tiber were 142.5% and 156.0% of those of the diploids respectively. The guard cells' diameter of tetraploids Sorbonne and Tiber were 112.6% and 160.8% of those of the diploids respectively. The characteristic of tetraploids stoma with that of diploid was compared. Stomata of polyploids are larger and spaced father apart on the undersurface of the diploids. The length of tetraploids stoma were 127.6% and 128.1% of those of the diploids respectively, the width of tetraploids stoma were 124.3% and 170.1% of those of the diploids respectively.The tetraploid plantlets and diploid plantlets of lily were carried out the low-temperature treatment, then their exosmosis rates of electrolyte and rates of damage of cytomembrane were compared. Under the same temperature, the electrolyte exosmosis rate and damage of cytomembrane of tetraploid plants were lower than diploid plants. It shows that the tetraploid lily's cold resistance and fight a drought are stronger than diploid lily.