Propagation Of Lycoris Bublets And Exploratory Research For Functional Genes Based On Transcriptome

The plants of Lycoris genus mainly originated and distributed in the east of China. They grow in very tough conditions and can easily fit in wicked environment in landscaping. These years they became popular in the market of cutting flowers, potting flowers, and landscape. But they were also restricted by the long life cyle and low proliferation, and can not meet the needs of the industrial development. Since most of the wild resources had been seriously destroyed till now, the most emergent thing today is to shorten the breeding periods, increase the proliferation,and improve the ornamental treats of Lycoris plants.Basing on survey of the wild resources of Lycoris sprengeri, we compared different culture skills like scales cutting and tissue culture, in the hope of shortening the developing period and increasing the proliferation. On the other hand, we use both chemical and radiation mutation breeding methods to investigate the ploidy of L. sprengeri. At the same time, the next generation of high-through sequenceing technique was used to build up the transcriptome library of L. sprengeri on the RNA level. Massive gene information was obtained, and the gene functions were predicted. According to this, the differentially expressed genes and their functions were compared between the juvenile bulbs and mature bulbs. Next, we will search for the genes related to bulb developing and metabolism pathways, which will definitely support the following molecular breeding of Lycoris. The majoy results were as follows:1. Among the three islands named Zhoushan island, Nanji island, and Mazu island, well preserved Lycoris sprengri were found. The habitata and plant community of I. sprengri showed differently. It meant that the L. sprengri was able to adapt to a wide ecological amplitude, and some mutant traits on the plants caused by the environment were discovered.2. Scale cutting were applied to L. radiate, L. aurea, and L. sprengeri. April was considered to be the best season to cut, when the survival rate and proliferation were highest. And the bigger the mother bulbs were, the stronger the reproductive capacity would be. Also, we found that the air culture of the four-excision scales generated many buds, and was a stable and effective method.3. In order to overcome the problems of polluting and browning which widely existed in the tissue culture, we compared different time of mercurous chloride treatment, the type of explants and many ways of pretreatment. As a result, using the twin-scales as explants was better than the four-excision scales, and laying the basal part of explant out of medium could also prevent the diffusing of pollution.20 mg/L VC was effectively stopping the browning.4. We used the bulblets from scale cutting as explants in tissue culure for the first time, and combined with liquid culture. Few pollution took place and massive buds came out immediately. By the way, the best medium component for buds inducing was 10 mg/L BA+0.5 mg/L NAA; and the combination of 8 mg/L BA+1-2 mg/L NAA was best for reproductivity.5. Bulbs of L. sprengeri were treated with colchicine, and 48 h of cochicine treating were fixed as the half-death time. According to the chromosome calculation of root tip, number and size of guard cells, as well as DNA content detecting by flow cytometer, some mosaic were produced. While the radiation of L. sprengeri bulbs by 60Coy killed many bulbs, and also produced several potencial mutants.6. Illumina's new generation of high-throughput sequencing technology was used to establish a transcriptome data library from the bulbs of L. sprengeri. A total of 98150 unigenes with an average length of 90 nt were generated,41.6% of these unigenes were annotated using BLAST. According to GO, COG and KEGG classification, lipoxygenase showed the highest expression level, and metabolic pathways were the most active pathways in L. sprengeri..7. Bulbs of different developing stage were sampled and sequenced by DGE. The expression level and annotated results indicated that much of the protein function was unknown. Compared with the transcriptome data base,4389 differentially expressed gene were found, and most of them were up-regulated.