| Tissue culture and its'regeneration is an important issue in plant gene engineering, it hassignificant effect on crop improvement.Tissue culture ability has been paid more attention ingene engineering and maize breeding, and it is controled by genetic factor, so it is urgent tounderstand its gendtics. In this research, diffrient explants of 30 genotype mainly from sweetcorn were cultured to value the regeneration ability and to establish compatible regenerationsystem. Based on the principle of genome collinearity in cereal, primer were designed fromOS22A sequence which related to rice regeneration ability. With the genome of 23 genotypemaize as template, PCRs were performed. The products of PCR were analyzed to explain maizeregeneration ability in DNA level. The main results of the study were summarized as follows:1.Callus were induced from mature embryos of 30 corn genotypes ,the results showed thatTD08,tianyuanhua,tianyuansui were the genotype with better regeneration ability. Theresults showed that the ability of callus formation from the mature embryo was popular easy in30 corn genotypes, but the induced frequency was greatly different between different genotypes,and callus quality were different between different genotypes.2.Induced frequency on MS and N6 medium were not notable difference in all genotypes.Different growth regulate material had great influence on the callus growing state, Proline canobviously improve the quality of callus, and cytokinin had some adverse effects to the qualityand growing state of callus.3. This research deals with studies on initiation, maintenance and differentiation of callusfrom mature embryo and immature embryo of thirteen genotypes in corn. The results showedthat the callus induced frequency were closely correlated between mature embryo andimmature embryo,correlation coefficient was 0.9653;the differentiate frequency were alsocorrelative between two kinds of explants, correlation coefficient was 0.9143;but thecorrelation coefficient between induced frequency and differentiate frequency was just0.4,this maybe related to the genetic controls of induced frequency and differentiationfrequency were not completeiy the same. The callus quality were obviously different, Calliobtained from immature embryo were generally batter than that of mature embryo. Thedifferentiation frequency were widely different between this two kinds of callus, only 2.5%differentiation frequency could be obtained on mature embryo callus, and the differentiationfrequency on immature embryo callus could be up to 83.3%.4.In the process of established regenerate system from shoot meristems,the mode of tussockybud occurring and multiplication of shoot meristems were all different.The ratio of hormoneto cytokinin was high that could urge shoot meristems created callus, otherwize, which couldbenefit to the occurring of tussocky bud.The multiplication of shoot meristems in differentmedium were very different, the figure of multiplication of shoot meristems could at mostreach 7-8 each shoot meristems (medium No23), the figure could at least only reach 1-2 eachshoot meristems (medium No22).5. Primers were designed according to express sequence OS22A related to regeneration inrice,7 pair primers selected from these primers were used in genetic diversity investigation ofthe 23 genotype.In total ,the 7 pair primers produced 144 polymorphic amplifiedfragments(144 alleles),the number of alleles locus averaged to 20.57 per primer with thevariation from 8 to 40.6. 23 genotypes of corn were classified into three groups according to the phenotype data ofrengeneration.In these three groups,these genotypes with high inducted frequency anddifferentiation frequency were classified into group 1. Those genotypes with high inductedfrequency and low differentiation frequency were classified into group 2. And thosegenotypes with low inducted frequency and low differentiation frequency were classified intogroup 3.7. 23 genotypes were classified according to the different alleles diversity. Through thecomparison of the gr...
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