Evaluation For Salt Tolerance Of Rice Bean And Functional Verification Of VumCYP78A6

Vigna umbellata((Thunb.)Ohwi &Ohashi),which not only has high nutritional and medicinal value,but also has the characteristics of high yield,disease and insect resistance and barren resistance,is a cultivated species of cowpea.It is of great significance to explore the excellent genes of rice bean for its genetic improvement and its related species.Firstly,the salt tolerance of 382 rice bean core germplasm resources was preliminarily identified.Besides,the function of VumCYP78A6,a candidate gene related to rice bean seed size,was verified on the basis of previous research,which laid a material foundation for rice bean variety improvement and excellent gene discovery.The main research results are as follows:1.Identification of salt tolerance of rice bean core germplasm resources:382 rice bean core germplasm resources were identified for salt tolerance at seedling stage.According to the salt stress index of each material,84 rice bean salt tolerant resources were preliminarily screened,including 74 moderate salt tolerant resources and 10 salt tolerant resources,but high salt tolerant resources have not been screened.The results showed that there was no correlation between seed size and salt tolerance of rice bean seedlings.2.Take rice bean materials with different grain sizes for transcriptome sequencing.The results of RNA-Seq analysis showed that 20297 genes were detected in the pod skin of FD28 and FDd33.Compared with FD33,1737 differentially expressed genes were detected in FD28,including 606 up-regulated genes and 1131 down-regulated genes.The go enrichment of differentially expressed genes was annotated to 57 functional groups of molecular function,cell biological process and cell components.3.The expression level of VumCYP78A6 in different rice bean germplasm was detected.The results showed that the relative expression of VumCYP78A6 in rice bean pod was significantly higher than that in seeds,and the expression level in FD28 was higher than FD33.4.The expression levels of VumCYP78A6 in different development stages of rice bean seeds were detected.The results showed that the expression of VumCYP78A6 was high in the early stage of rice bean seed growth and development.With the growth and development of seeds,the expression of VumCYP78A6 showed a decreasing trend.5.Cell sections showed the number of pod skin cells in different in large grain rice bean materials was significantly higher than that in small grain rice bean materials.6.The expression level of VumCYP78A6 was detected by qRT-PCR.The results showed that the expression level of VumCYP78A6 in transgenic Arabidopsis lines was significantly higher than that in wild-type.7.The pod grown for about 2 weeks and mature seeds of Arabidopsis were taken to observe the phenotype.The results showed that the pod length / width,seed length and 1000 seed weight of transgenic Arabidopsis were larger than those of wild type.