Improving Rice Starch Quality Via Molecular Marker-Assisted Selection and Transformationin of Antisense Wx Gene;

In order to produce selectable marker-free (SMF) transgenic rice containing antisense Wx gene, two T-DNA regions, with the HPT selectable marker gene and the antisense Wx gene, respectively, in two binary vectors or a super-binary vector, were constructed and co-introduced into several rice cultivars, both of Japonica and Indica, by Agrobacterium tumeficien(s)-mediated co-transformation system.

The functional mechanism of waxy protein and Wx gene,the allele mutant of Wx gene,the production ways of waxy mutant lines,the quality and property of waxy wheat and its uses were summarized,which were involved in the internal and external research.

The results showed that the materials with GG-type of Wx gene had higher AC and lower GC,however,the materials with TT-type of Wx gene had moderate AC and higher GC;there were significant negative correlations between AC and GC、GT.

Based on the results of genotype identification,the waxy wheat s improved BC5F2 backcross progenies were used in this study to verify the effects of null alleles on reducing amylose content,determine the amylose synthesis capacity of each Wx gene,and investigate the correlation of amylose content with agonomic traits,quality traits and starch pasting properties,respectively.

This paper reviewed the studies on waxy wheat and Wx genes at home and abroad,including the quality characters,selection and identification of Wx genes and waxy individual,the molecular biology of Wx genes and,waxy wheat breeding ect.