Breeding And Cultivation Of New Ornamental Plant Varieties On Lycoris Herb.

Lycoris Herb. is one of the most important flowering bulbs, widely distributed in the southern subtropical regions of China,and has great potential for the development and utilization because of its unusual flower and numerous variation. Conventional breeding and molecular marker-assisted breeding methods were carried on the breeding of new varieties in this article. SSR molecular marker analysis protocol was established and was used on the correspondence analysis of fancypoints in L. chinensis.Tissue culture of L.sprengeri and the bulb cultivation techniques of L.radiata were studied respectively. Results are as follows:1. A number of clones with special ornamental value were selected as follows: 61 L. chinensis, 37 L. radiata, 24 L.sprengeri and a small amount of L.longituba, L. straminea, L. houdyshelii, L. aurea, L. albiflora, and a total of 138. First-hand information of these clones was obatianed through observations which provide support for cultivar assessment.2. Inter-species hybridization among 5 species was carried out. Results showed that: hybridization among fertile diploid hybrid parent groups was easy. And its seed between 0.86².92 on average, which was below compare with fertile diploid hybrid parent groups except L. chinensis. Analysis of reciprocal cross experiments showed that the number of hybrid seed depends on its female parent.3. An SSR molecular marker analysis protocol was established in L. chinensis, which had a total volume of 20μL containing 0.5 U of Taq DNA polymerase, 1.5 mmol·L^-1 Mg²⁺, 0.125 mmol·L^-1 dNTP, 0.5mmol·L^-1 primer and 50 ng of template DNA. This protocol had been applied to an analysis of 8 species of Lycoris and 35 clones of L. chinensis with 7 and 9.5 polymorphic loci per primer on average obtained, respectively, which reflects a good performance in universality and stability of this protocol. Analysis of the corresponding relation between SSR loci and such traits as scape height and flowering time had preliminarily shown that loci Ly 97 and Ly 98 were correlated with late flowering time'Oct'as well as that loci Ly 84, Ly 87 and Ly 97 with scape heights'Mid'and'Low'.4. The leaf blades and embryo of L.sprengeri were cultured in vitro.The results showed that high induction frequency, 75.8% on average, was obtained on embryo culture. The most ideal callus induction medium of embryo culture was MS+6-BA 2mg·L^-1+2,4-D 2 mg·L^-1+ Sucrose 60g·L^-1,while the most ideal clustered shoots induction medium was MS+6-BA 2mg·L^-1+2,4-D 1 mg·L^-1+ Sucrose 30g·L^-1. The results of leaf tissue culture showed that the induction frequency of young leaves was 65.8% on average which was higher than that of mature leaves(13.5% on average). The most ideal induction medium of young leaves tissue culture was MS+6-BA 20mg·L^-1+NAA 1mg·L^-1+Sucrose 30g·L^-1。5. The effects of fertilizing amount on L. radiata were studied, including the soil nutrient, blade nutrient, bulb weigh and circumference. The result indicated that the bulb weight and circumference increment trends of change in different fertilizing amount treatments present unimodal curve. The maximum bulb growth was higher than control group with 15.7%, while, excessive fertilizing amount stunted the growth. A fertilizing model was evaluated on the basis of soil fertility. Leaf analysis was studied on nutrition diagnosis method. The result showed that the critical concentration of leaf nutrient element was 3.05%,19.40%,31.29% respectively on N,P₂O₅,K₂O,above which was necessary on ensuring a high output.