Optimization Of The Transformation System And Transformation Of Gene Resistant To Dwarf Mosaic Virus Of Zea Mays L.

Maize （Zea mays L.） is the highest production cereal crops in the world, can be consumedas food, feedstock, industrial raw materials and other variety of uses, and therefore plays animportant role in agricultural production. Maize dwarf mosaic disease is a global agriculturaldisease. The resistance to dwarf mosaic virus in maize is controlled by minor quantitivegene/loci, so it is difficult to be used in maize breeding ststyems. However, these genes couldbe efficiently transferred to maize varieties through genetic transformation.To establish the excellent transgenic receptor system in maize, break the genotypes limit ofmaize embryogenic callus induction, and optimize maize genetic transformation system, theline Zheng58（good） and Chang7-2（poor） were as the material which difference ability on theimmature embryo culture, for analysis endogenous hormones difference in the explant（immature embryo） and the process of callus induction; According to the characteristics of GUStransient expression and the proportion of resistant callus, the agrobacterium-mediated and genegun transformation system were optimized and compared, and anti-dwarf mosaic virus genewas transformed to line E28, Zheng58and Qi319by gene gun transformation optimized system,the resistance of transgenic offspring were analyzed.1. The key hormones of affecting maize embryogenic callus induction were explored.Studies suggested that: For explant （immature embryo）, the lower the ABA and GA₃/Z weremore conducive to the initiation of callus induction; At the shooting callus stage, higher ABAand lower GA₃inhibited the growth of shoot and promoted the formation of callus; Callus growquickly after the removal of buds, higher IAA/ABA is more conducive to the formation ofembryogenic callus; When embryogenic callus formation, the higher levels of IAA, Z andIAA/Z has an important role for maintain good embryogenic callus.2. Disseminated intensity, culture temperature and surfactant in Agrobacterium-mediated,and bombardment pressure, the bombardment distance in gene gun were optimized; and twotransformation methods were compared. The results showed that: OD6000.6,30min,25°C for3days, and with0.01%Silwet L-77were the optimal parameters in Agrobacterium-mediated. When the vacuum is-0.095MPa, that4.5MPa,11cm bombardment distance were the mostappropriate for gene gun bombardment. Compared Agrobacterium-mediated and gene gunbombardment, we found that gene gun bombardment was more benefical to the transfer geneticoffspring obtained than Agrobacterium-mediated in.3. Anti-dwarf mosaic virus gene were transformated to inbred lines E28, Zheng58andQi319by gene gun method optimized system, and their transgenic offspring dwarf mosaic virusresistance were analyzed.28positive plants were obtained by detection of target gene and bargene. By the SCMV artificial inoculation of virus identification, different levels of virusresistant were existed in transgenic progeny. Plant resistance of2matirials （Vector ofpCAMBIA3301-CNSP transformated to line Zheng58and Qi319） and PCR detection of6matirials （Vector of pCAMBIA3301-CNSP transformated to line Zheng58, Vector ofpCAMBIA3301-CNFP transformated to line Qi319, vector of pCAMBIA3301-CNSPtransformated to4lines Qi319） PCR detection were corresponded Mendelian laws, thoseprovide new disease resistance germplasm resources for mazie breeding.