The Genetic Analysis Of Wheat Spiker Inhibition Characterization And The Study On Expression Characteristics Of The Related Genes

Developing the wheat new germplasm from the distant hybridization is an effective means for the wheat genetic breeding. A new wheat line 3558-2 is selected from the progeny lines of the cross between Fukuhokomugi and A. cristatum (L.) Gaertn (National Gene Bank accession number Z559). These lines had normal natural tillers, but have few effective spikes. The paper report the genetic mechanism and gene expression regulation on molecular level for the spike inhibited character. Altogether 572 F2 populations from the crosses between the wheat spike inhibition plant lines and Jing 4841 which is normal in tillering and ear formation. In order to study the characterization of this trait, we apply the molo-segregating generation of genetic system of quantitative traits to analysis the genentic characteristics of wheat spike inhibition trait. The results shows the trait about the number of the spike per plant is controlled by two major genes, and the interaction between the two major genes also can be detected. In order to isolate the differentially expressed gene which regulate the spike inhibited characteristics; we carry out the gene expression regulation analysis by using gene chip technology. By comparing the gene expression profiling of single spike material and multi-spike control from spike inhibition line, the results showed that there were 77 induced expression genes and 21 inhabited expression genes, which expression levels are all above 5 times. The gene expression profiling results showed that there are very seldom differentially expressed genes between the two materials. Interestingly, two genes MIOX and ABI5 are down-regulated in spike inhibition materials. We cloned the full length cDNA sequence of the two genes. Then we complete the expression level analysis among the extreme phenotype materials without effective spike, the plant with only one effective tiller and the plant of with multiple effective tillers. The results of the semi-quantitative RT-PCR showed that MIOX and ABI5 expressed with a lower level in the leaf of the effective tiller, and expressed with a higher level in the leaf of spike inhibited tiller. Therefore, we suggested that the high level expression of the two genes is related to the character of the wheat spike inhibition trait.