Construction And Majorization Of Maize Immature Embryo Culture System Serving As Transgene Acceptor

Ten elite lines, chang7-2, zheng58, xun9058, 87-1, 478, Qi319-red, 9801, Ji533, Dan598 and Ji853, which are widely used for maize breeding, were presented for Immature embryo culture research. We set up callus induction, subculture, differentiation and plant regeneration experiments to investigate the callus induction rate, embryogenic callus induction rate, callus cloning force and green plantlet differentiation rate, and to determine the wide adaptability maize immature embryo culture medium at all stage. We screened out maize inbred lines with strong immature embryo culture capability and their corresponding optimal medium. The evidence of the best length of immature embryos inoculation was shown and the maize transgenic receptor immature embryo culture system was created. The main results were as follows:1, Through the research of induction, subculture and differentiation with 10 different maize inbred lines by using N61, N62, N63, MS1, MS2, MS3, MB1, MB2, MB3 nine induction and subculture medium, and F1, F2, F3, F4 four kinds of differentiation medium, the results showed the N62, MB2 and F2 were wide adaptability mediums for callus induction, subculture and differentiation phase respectively.2, Using orthogonal design to analyze the influence of 2,4-D, L-pro and CH 3 on callus cloning force, The optimal ratio of their combination was 2,4-D (2.0 mg / L), L-pro (700 mg / L) and CH (500 mg / L), also suggesting the optimization ratio of subculture stage.3, Through the experiments of various stages of induction and culture of 10 maize inbred lines Chang7-2, Zheng58, Xun 9058, 87-1, 478, Qi319-red, 9801, Ji533, Dan598, Ji853 and using an average rate of callus induction, embryogenic callus induction rate, callus clone force and the rate of green plantlet differentiation as the evaluation criteria, we screened out the optimal Immature embryo culture system for Qi319 - Red, 87-1 and 9801.4, By the comprehensive comparison of embryogenic callus induction rate, induction rate of embryonic callus and callus growth quality, the appropriate length of immature embryos inoculated was 1.5 ~ 2.5mm, At this length, immature embryos had good callus induction ability, fast growth, crisp texture, bright color, high rate of embryonic callus and conducive to plant regeneration. 5, At the each stage (induction, subculture and differentiation) of maize immature embryo culture, there were significant differences universally between the genotypes, and more obvious at the differentiation stage. Comparatively speaking, the effects of the culture medium composition on tissue culture of the various stage was far less than genotype. Genotype of maize immature embryo culture was still the key to the success.6, By correlation analysis on maize immature embryos callus induction rate, induction rate of embryonic callus, cloning force and the rate of green plantlet differentiation, callus induction rate had a marked influence on the induction rate of embryonic callus, the induction rate of embryonic callus had a marked influence on the rate of green plantlet differentiation. Cloning force had a marked influence on the rate of green plantlet differentiation. Therefore, the materials being lower callus induction rate or weak cloning force should be weed out.