Genetic Analysis Of Stripe Rust Resistance Gene In Durum Wheat ‘V.1135' And Cloning Of TaNHO1 Gene In Wheat (Triticum Aestivum. L)

Wheat is one of the food crops closely related to human life.However,due to wheat powdery mildew and stripe rust caused by airborne fungi,the annual yield of wheat will be reduced to varying degrees,and when the disaster is serious,it can lead to a large area of yield reduction,or even crop failure.The control of its harm can start from the aspects of agricultural control,chemical control and breeding of resistant varieties,but the most economical and effective mean is to cultivate resistant varieties.By introducing the resistance gene into wheat varieties with good agronomic characteristics,the combination of the two genes was achieved and the yield of wheat was increased.With the rapid variation of fungus,it is difficult to maintain the resistance of disease resistance genes for a long time,and the disease is aggravated.Broadening the disease resistance spectrum of wheat and exploring broad-spectrum resistance genes will be the key to solve the problem of wheat disease resistance in the future.Durum wheat?Triticum durum?is a secondary gene pool of common wheat,which contains a large number of excellent genes that can improve the quality of wheat.In the process of searching for resistance genes to wheat powdery mildew and wheat stripe rust,many genes derived from close relatives of common wheat.NHO1 gene has non-host resistance?Non-host resistance,NHR?in Arabidopsis thaliana.NHR is one of the most common forms of plant resistance to most pathogenic microorganisms.Compared with R gene,it is characterized by no race specificity.It is relatively stable to some pathogenic bacteria and even to the whole genus and species,and will not lead to the loss of resistance with the evolution of races,so it has the characteristics of broad-spectrum durable resistance.Therefore,the study was based on durum wheat in wheat secondary gene pool to definite the genetic mode of resistance gene and accelerate the discovery of resistance gene in wheat relatives,and the concurrent resistant germplasm N9134 was taken as the research object.Wheat NHO1 gene was cloned by RT-PCR,and analysised its expression,subcellular localization and promoter sequence.This study provides basic data for broadening the disease resistance spectrum of wheat and explores the mechanism of non-host resistance genes in wheat.In order to achieve the purpose of long-term prevention and control of diseases and increase wheat yield.The main results of this study are as follows:1.The results showed that durum wheat V.1135 was resistant to the tested stripe rust races.The genetic analysis of disease resistance of V.1135 at seedling stage was carried out by using CYR33 race.The genetic analysis of F₂ generation crossed with two highly susceptible durum wheat TUR.SNO.1076 and V.1172 to CYR33 race and the parents of sympathetic disease to Tiaozhong 33 showed that the resistance to CYR33 was controlled by two pairs of dominant genes.2.Through SSR molecular marker screening,we mapped a pair of resistance genes on chromosome 7B,which were proximal linked to Xwmc273,Xcfa2040 and Xwmc276 markers.The disease resistance spectrum and disease resistance type analysis results showed that it may be a new disease resistance gene.It lays a foundation for further analysis of the action site and allelic test of the gene.3.Based on transcriptome analysis and genome sequencing,wheat NHO1 gene transcribed from three homologous chromosomes was cloned from resistant germplasm N9134,belonging to FGGY family of NBD-glycokinase-HSP70-actin superfamily.The changes of wheat powdery mildew E09 after infection were analyzed by qRT-PCR,which showed that it could respond to the infection of powdery mildew;By analyzing the sequence of homologous gene promoter region,it was found that the promoter region of the gene contained a large number of cis-acting elements that could respond to plant hormones and stress resistance and disease resistance,which meant that it could be induced by a variety of plant hormones and participate in the process of wheat disease resistance.The localization of green fluorescent protein confirmed that its action site mainly acted on the cytoplasm,cell membrane and nuclear membrane,which made up for the gap of the gene in this research field,and confirmed the subcellular localization results according to its function.This study lays a foundation for further analysis of the specific function and mechanism of wheat NHO1gene.