Genetic Diversity And Gene Variation Analysis Of The Variants Derived From Genome DNA Transformation Of Wild Rice

Abstract:In an attempt to increase the genetic diversity of cultivated rice and to enhance heterosis of hybrids, genomic DNA of either Oryza minuta or O. eichingeri was injected into the plant of a restore line of hybrid rice, RH78, through the spike-stalk injection method. A set of23variant plants were derived from the first generation. It was found that the variants were morphologically different in traits such as flag leaf length and width, plant height, the number of panicles per variant plant, panicle length, spikelets per panicle, seed set, and weight of100grains. Several variant plants are much improved compared with the receptor in yield related traits and have good plant type, can be good candidates for super hybrids breeding need. Moreover, both donor and non-donor alleles were detected among the23derivatives and the parents through240microsatellites and InDel marker assays. Furthermore, a molecular statistical analysis was performed based on allele frequencies obtained by genotypic data, which also showed that spike-stalk injection method is an effective means of inducing genetic variation as well as increasing genetic diversity. The results will be useful for molecular breeding in the future.YVB is a variant line derived from V20B transferred genomic DNA of O. minuta through spike-stalk injection method. The agronomic traits of YVB including plant type, grain quality and yield traits are different, partial improved greatly. Based on whole genome sequencing of two materials, we made a comparison of sequences of27genes which mainly affect those variant traits.208SNPs and98InDels are found between variation YVB and recipient V20B.43SNPs are found in coding sequence and24SNPs are missense mutations. There are6InDels in coding sequence,4even caused a frame shift. Several mutations even cause variations in protein sequences and structure, which will give insights into mutations that lead to phenotypic variation.Several genes are resequnced in variant material, the donor and the receptor, then over400bp in the5’UTR of Wx are found to be indentical to the donor but different from the receptor, which demonstrates the influence from the donor again. Moreover, Fluorescence quantitative PCR is carried out to test the quantity of gene expression. At last, gene variation in non-coding sequence is predicted to cause the RNA expression difference in two materials, which is crucial for associating the phenotypic variation.