Analysis Of Tissue Culture And Genetic Variation On Medicinal And Edible Lily Hybrid Progeny

This study used Lilium pumilum,Lilium davidii var.unicolor,Pollyanna,Prato and White heaven as materials,and used direct pollination to self-cross,inter-species hybrids and inter-species hybrids to observe the seed setting rate,ovary and seeds of each hybrid combination.The development status provided a theoretical support for the selection and breeding of new varieties and germplasm innovation.In order to expand the number of offspring and perform early selection of genetic heterogeneity of hybrid offspring,tissue culture and propagation system was established using the leaves of the offspring of L.davidii var.unicolor × L.pumilum as well as bulbs of L.davidii var.unicolor.Genetic diversity of Progenies and parents of Rn×LZ and SZ×LZ was analyzed by SSR markers,which provided reference for early selection of hybrid progeny.Results of this study were as follows:1.characteristic of setting,development of ovary and seed.Comparison of the seed setting rate,seed swelling rate,ovary expansion rate and germination rate of 10 hybrid combinations and 3 parental inbred combinations.It was found that the comprehensive index of the 3 parental inbred was White heaven> Prato> L.pumilum.Comparison of seed setting between the 8 groups,the seed setting rate,seed filling rate,ovary enlargement rate and seed germination rate of L.pumilum×L.davidii var.unicolor Lily hybrids were higher than those of other hybrid combinations.The rate of seed setting,seed swelling,ovary enlargement and seed germination of Pollyanna×L.pumilum were lower than other crossings.In the cross between Asiatic hybrids,the seed setting of Pollyanna×Prato was higher than that of Prato×Pollyanna.However,seeds of Prato×Pollyanna failed to germinate.2.Establishment of tissue culture propagation system for lily hybrids.Using scales of Lilium davidiias explant and MS+1.0 mg/L 6-BA+ 0.2 mg/L NAA as adventitious bud induction medium,the induction rate reached 93.3%.MS + 1.5 mg/L 6-BA + 0.5mg/L NAA was the best medium that can induce adventitious bud when using leaves of hybrid progeny as explants.In the subculture of the support of Lilium pumilum populations and hybrid combinations,with the increase of generations,the differentiation rate and value-added coefficient gradually decreased,and the differentiation is basically no longer in the fifth generation.In the subculture of all parents and offspring,when the third and fourth generations are subcultured,vitrification was observed.the rate of vitrification for the fifth generation was more than 10%,showed that it is not suitable to subculture after four generations.The best rooting medium is 1/2 MS + 0.2 mg/L NAA.3.Analysis of genetic diversity of hybrid offspring population based on SSR markers.The average polymorphism percentage of 11 pairs of primers was 70%.Shannon’s information index(I)was 0.661.The average value of Nei’s gene diversity(H)was 0.367.the mean effective allele number(Ne)was 1.889 and PIC value was0.358.it was indicated that the 11 pairs of SSR primers showed certain polymorphism and can be used for further genetic diversity analysis.Based on the amplification results,a total of 83 offsprings of Rn×LZ and parents were analyzed.At a distance value of0.53,they can be divided into four categories.The first category included male parent LZ and progeny R35.The second category included all female parents and offspring R2,R14,R3,R4,R9,R20,R22,R56,R8,R13,R16,R21 and R23.The third category contained 29 offsprings and the fourth category included 11 offsprings.A total of 64 offsprings of SZ×LZ and parents can be divided into seven categories when the distance value is 0.614.The first category included all male parents and S3.The second category included all female parent and S17.The fourth and sixth category included S37 and S50,respectively.The third,fifth,and seventh categories contained 14,9,and36 hybrid offsprings,respectively.based on the genetic distance of offspring and their parents for crosses Rn×LZ and SZ×LZ,it can be seen that the genetic distance between female parent and offspring is smaller than the genetic distance between male parent and offsprings.