Isolation And Expression Analysis Of ALDH Superfamily Genes From Chrysanthemum Lavandulifolium And Genetic Modification Of Cut-Chrysanthemum Using DlBADH

Cut-chrysanthemum occupies a decisive position in the global flower economy. But most part of north China suffers serious water shaortage, soil salinization, and enormous energy is consumed during cut-chrysanthemum cultivation. Therefore, the breeding of new cut-chrysanthemum cultivars enduring drought and sanility has an important meaning. Cnomile (Chrysanthemum lavanduiflium) which is one of the wild species near the source of the cultivated-chrysanthemum, can resist strong abiotic stress as a kind of halophytes, and contained rare good genetic resources for chrysanthemum stress resistance modification. This study takes our group independently nurtured three new varieties of cut chrysanthemum,"Xue Shan","Xue Shen’ and "Fen Guiren" as the materials. By these materials, the research constructs their efficient regeneration and genetic transformation system for the first time, and isolates chamomile effective stress resistance genes to build the plant expression vector. This vector is transformed into "Xue Shan", in order to improve drought and salt tolerance. The conclusion obtained as follows:1. Seven full length genes ALDHs named CIALDH2-2、CIALDH3-2、CIALDH3-1、CIALDH5、 CIALDHIO、CIALDH12、CIALDH22and two sequences of fragments named CIALDH6, C1ALDH7were isolated from chamomile. The two genes who are involved in glycine betaine (GB) synthesis were also abtained in this study. Time and space specific expression patterns were analyzed. The result showed that all these genes were responsed to high salinity, but differs to drought, heat, low temperature, ABA and SA. The gene D1BADH can be induced by several stresses to up-regulated express. The twogenes involved in GB synthesis can be up regulated by high salinity, heat and ABA induction, dipping and heaving. Above these, the gene D1BADH was chosen to improve abiotic tolerance of cut chrysanthemum. 2. Stable regeneration system was established for’Xue Shan".’Xue Shen" and "Fen Guiren". It is found that various cultivars or different organs of one cultivar perform distinct reaction. Of all theses, with a high generation rate, easy differentiation, leaves of ’Xue Shan" is a good material for build a transformation system3. Plant espression vector pBI121-BADH was established by vector pBI121and the gene DIBADH. Then agrobacterium-mediated leaf disc transformation was used to construct genetic transformation system of "Xue Shan", and shift the gene DIBADH to cut-chrysanthemum. At last,36transgenic regenerate lines were obtained, and5of the36regenerate lines were positive. Positive transgenic ratio is4.77‰.These above results indicate that excellent gene resources, approperate chrysanthemum cultivar, and suitable methods play an importanct role in the resistance improvement of chrysanthemum.