| It is because that the excellent acceptors for maize transgenic engineering are insufficient in our country, especially in the southwest mountain areas of china andhereditary variation regularity for the two characters such as efficiency of embryonic callus induction and number of regenerating plant (these two characters were abbreviated to the nduction efficiency and number of regenerating in the following of the paper, respectively), which hint the maize culturing capacity, is not very clear. Therefore, aiming at picking out superior acceptors, we had made systematic researches on the two characters with combing traditional quantitative-character genetic analyzing methods such as single-factor genetic mating design, diallel crossing genetic design, genetic effect analyzing method and the modern molecular locating method such as QTLs'. The main results are followed.(1) 50 superior inbred lines and about 30 crosses in our country, especially in the southwest of China were used for identifying and selecting the superior genotypes in the above two investigated characters under the same culturing condition in 2000 and 2001. There was very significant difference among the genotypes in the both characters. But the two characters were not certainly related. Some genotypes such as 18-599(hong) and 18-599(bai) were very good in them. For some ones such as zong 31, induction was higher than 18-599(hong) and 18-599(bai) in the efficiency, but it was only 1/3 to the later in regenerating number. In some genotypes such as S37, R08, R15, PI38, A318, induction efficiency was just about 3% and scarcely any regenerating plants were got. On the whole, hybrids acted better than inbreeds in the both characters.(2) Two kind of inbreeds were selected as parents of the Grifflng's method 1. 18-599(hong) and 18-599(bai) and the inbred line zong 31 are one kind because they are not only superior in the characters of maize cross breeding, such as CA, resistance to disease and the important agricultural characters, but also excellent in transformation characters as the induction and regeneration. A318, P138 and R15 were taken as the other kind as they are good in crossbreeding, but bad in the transformation. According to Griffmg's method 1, diallel crossing was built and CA was analyzed. Variance analysis showed that there were the greatly significant difference among the both of GCA in inbreeds and SCA in crosses, respectively. The high GCA of 18-599(hong) and 18-599(bai) and the low SCA variance of their crosses showed the strong and stable heredity on the both characters. Taking them as parents, the generations with high and stable induction and regeneration will be gotten. As for inbreed zong 31, although GCA of induction frequency was highest and GCA of regeneration number was the third, SCA variance of its cross was high. So the inbreed zong31 can be inherited strongly but not stable to its descendant. As for the other inbreeds such as A318, P138 and R15, the effect values of GCA were negative. In a word, the excellent inbred lines in maize cross breeding 18-599(hong) and 18-599(bai) are also the most prospective and valuable inbreeds for maize immature embryo culture in this research.(3) In the analysis of the diallel crossing genetic mating design, Hayman's genetic analyzing method was also taken into for exploring the genetic model of the above two culture characters (induction efficiency and number of regenerating). Additive-dominance genetic model was found to be functional to the nduction efficiency. Dominant effect is from partial to complete and most of them act minus. As for the number of regenerating, the results from two testing methods of the regression analysis based on the data of Wr and Vr ,and the variance analysis based on the data Wr+Vr and Wr-Vr were not certain.Linkage or other complicated things may be existed for this character. It is also possible due to the fewer parents in this diallel crossing, or that the datum for this character is not perfectly according with the basic need of the statistics...
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