Functional Analysis Of TaRsfS Gene In The Interaction Of Wheat With Stripe Rust And Powdery Mildew

Wheat stripe rust and powdery mildew are the two most important diseases on wheat in China.Breeding and planting resistant varieties are the most economical,effective and environmentally method to prevent wheat stripe rust and powdery mildew.However,due to the high variability of single-source resistance and pathogen toxicity of wheat resistance breeding in China,the resistance of resistant varieties is often difficult to obtain in the production practice.Therefore,it is important to clarify the molecular mechanism of wheat resistance to stripe rust and powdery mildew for disease control and long-term use of variety resistance.The wheat variety Xing Min 318 was resistant to stripe rust and powdery mildew.Through proteomic analysis,a ribosomal silencing factor TaRsfS,which plays a role in the interaction between wheat and stripe rust and powdery mildew,was screened out.Based on the basic bioinformatics analysis of the gene,the expression of gene in wheat and stripe rust and powdery mildew interaction was analyzed by q RT-PCR.Then,the function of the gene was analyzed by VIGS technology and tobacco transient expression.Finally,the expression analysis of hormonal and abiotic stress was carried out on the gene.Mainly obtained the following research results:1.Bioinformatics analysis results showed that the the Open Reading Frame(ORF)of the gene contains 684 bases encoding 227 amino acids.the transmembrane domain and signal peptide were not included in the gene structure;the gene contains the Rsf S conserved domain,and the similarity with the Rsf S conserved domain of barley is as high as 95%,which can be preliminarily named TaRsfS;using online software predicted that the gene was located in the cytoplasm.2.q RT-PCR technique was used to analyze the expression characteristics of TaRsfS at different time points after inoculating stripe rust and powdery mildew in wheat variety Su Won11.The results showed that the expression of genes in the compatible combination CYR31 and the incompatible combination CYR23 of wheat and stripe rust were up-regulated.However,in non-affinity combinations,the expression of genes was significantly up-regulated at 96 hours after inoculation;in affinity combinations,there was no significant change in the expression of TaRsfS.After inoculation with powdery mildew E09,the expression level of the gene has been in an upward trend,and the upward multiple has gradually increased.3.Knocking down TaRsfS gene expression by virus-induced gene silencing.Then inoculating with stripe rust fungus CYR31,the susceptibility of plants increased and the number of stripe rust urediospores also increased.Histological observation showed that the expanded area of the stripe rust fungi in TaRsfS silenced plants was larger than that in the unsilent plants.All the resulted showed that this gene positively regulates the resistance of wheat to stripe rust in the process of interaction between wheat and stripe rust;After inoculation with powdery mildew E09,the resistance of the silenced plants increased.The histological results showed that the expansion of mycelia of powdery mildew in TaRsfS silenced plants was inhibited,and this gene mainly acted in a negative regulation during the resistance of wheat to powdery mildew.The above results indicate that the TaRsfS gene plays an important role in the resistance of wheat to stripe rust and powdery mildew,and the regulation modes of the resistance to two diseases are different.5.Hormone and abiotic stress treatment of TaRsfS gene showed that the expression of TaRsfS gene could induced by salicylic acid(SA),jasmonic acid(JA),abscisic acid(ABA)and ethylene(ET),however,the up-regulated expression was more obvious after ET induction.During abiotic stress treatment,the expression of TaRsfS gene was up-regulated by high temperature and drought treatment induction;while down-regulated by salt treatment.This indicated that this gene can respond to a variety of hormonal and abiotic stress stimuli.In addition,the distribution of it in roots,stems and leaves of wheat plants was detected,the results showed that the gene was distributed in roots,stems and leaves,and the expression of which was highest in the leaves while was lowest in the stem.