Transcriptomics Researches On Wheat(Triticum Aestivum L.) Grain Development Morphogenesis

Wheat yield elements determine that studying the wheat grain developmentmorphogenesis and dry matter accumulation mechanism has important theoretical andpractical significance for wheat yield increase and flour quality improvement. The presentstudy chooses a specific big size wheat variety as the research material. Morphology,cytology and transcriptomics method were used to systematic study the transcriptomics ofwheat grain development. Different expressed regulatory genes are classified by the graingrowth curve slope and the dry matter accumulation curve slope and two differentmechanism which regulate the grain morphogenesis have been elucidated. The mainconclusions are as followed:1. Wheat grains are morphogenesis at DAP12. In this period, the grain growth curveslope and the dry matter accumulation curve slope are obviously different, indicates that themechanism of the grain morphogenesis and the dry matter accumulation are independently.2. Denovo assemble combined with wheat genome based assemble and wheat Unigenemap guided assemeble is the best stategy for wheat transcriptome reconstruction.3. In the present study, referring to the genome sequence of Chinese spring, a highquality transcriptome associated with wheat grain morphogenesis is establised using thehybrid assemeble strategy. The number of total sequences is212223and the average lengthis715.7bp.4. Grain development morphogenesis genes are classified into two expression models,include the grain length growth curve and dry matter accumulation. 5. The wheat grain development is regulated by two mechanism. one regulates grainmorphogenesis, and the other is controlling dry matter accumulation.6. Many important genes which regulate grain development are discovered involvingplant hormone metabolism, cell growth, material transportation and nutrient storage, etc.This research mainly includes the following aspects of innovation:1. The morphology, cytology combined the transcriptomics are applied to study theregulation mechanism of wheat grain morphogenesis.2. Make full use of wheat genetic data resources, and a high quality wheat graintranscriptome is established by hybrided strategy.3. Evaluate the assembly algorithm, programs, options, methods and strategiessystematicly, and a set of complete index for assemebly are established.4. Grain growth and dry matter accumulation curve slope are innovative applied toclassify the grain regulatory genes, which decreasing the subjective and increasing thescientific in gene filtering of transcriptome analysis, and it provides a reasonable andefficient method to study the function of unknown genes.5. Many important genes which involving grain morphogenesis and dry matteraccumulation are discovered.Regulation mechanism of wheat grain development is extremely complex, to fully andaccuratly understanding of the mechanism is a long way and need reasonable experimentaldesign and more powerful technology.