Genetic Stability Analysis Of OsPT2 And OsPT6 Transgenic Soybean And Cloning And Basic Functional Analysis Of Candidate Genes For Tolerance To Low Phosphorus

Phosphorus is essential elements for plant growth and developments,accounting for about 0.2%dry weight of plant body,which mainly involved in the main metabolic processes in crops such as carbohydrate synthesis and transport,protein synthesis and decomposition,and fatty synthesis.Soybean is one of the most common phosphorus performance crops.Therefore,as one of the essential elements in the growth and development and yield accumulation of soybean,phosphorus as is indispensable.But the effective concentration of phosphorus in the soil is very low,and the application of phosphate fertilizer is very easy to be fixed at topsoil,so the most effective way to solve this problem is to improve the ability of low phosphorus tolerance in soybean.Although there is a certain understanding for the molecular mechanisms of plant responses to low phosphorus stress according to the development of modern molecular biology,the researches mostly focused on the model plants,there is a few research reported in soybean.Therefore,genetic stability analysis and cloning and preliminary function study of a candidate gene OsPT2 and OsPT6 with low phosphorus tolerance base on the previous researches in transgenic soybean.The main results obtained were as follows:1.The growth difference of 15 soybean cultivars under normal phosphorus level and low phosphorus level was statistically analyzed in the low phosphorus stress treatment.The results showed that the ability of low phosphorus tolerance was relatively stronger in Lu Ning 1,Gandou 8,Zheng 9805 varieties,while the ability of low phosphorus tolerance was relatively weaker in Wandou 24,Jindou 34,Nannong 1138-2 varieties.2.The genetic stability analysis was conducted for transgenic soybean expressing OsPT2 and OsPT6 genes in T6 generation.The results showed that the transgenes OsPT2 and OsPT6 encoding phosphorus transport protein can be stably inherited and expressed in the transgenic progeny,thus it is ideal material for transgenic breeding.3.Using the T5 generation of transgenic soybean expressing OsPT6 as material,the cDNA library of root under low phosphorus stress was analyzed by the digital gene expression profile analysis,33 differentially expressed genes were obtained.the results of GO functional enrichment significance analysis and KEGG metabolic pathway analysis showed that it could be the main way for adapting to low phosphorus stress to affect the secondary metabolic pathways in soybean through there gulation of activity of the enzymes involved in photosynthesis to control photosynthesis rate.4.A gene GLYMA06G20730 specific expressed in super gene family of peroxide was selected by digital gene expression profile analysis,the CDS sequence length of this gene is 969bp,we cloned this gene by homologous cloning method,namely as the GmPODl.Bioinformatics analysis showed that its isoelectric point is 5.01,and molecular weight is 34.215kD.Then the recombinant plant overexpression vector pCAMBIA3301-GFP-GmPODl was constructed and transformed into Arabidopsis thaliana,and the obtained T1 generation will be used for the next validation.