Pangenome Assembly Of Wheat Stripe Rust And Population Structure Analysis Of Wheat Stripe Rust In Central And Western China

Wheat stripe rust is an important airborne fungal disease worldwide,caused by Puccinia striiformis f.sp.tritici(Pst).The disease epidemic in wheat planting areas of China which led to about 4 million tons of wheat yield loss every year.The mothed of planting disease-resistance varieties is the most economical,effective,and environmentally friendly measure to control wheat stripe rust.We are breeding effective disease-resistance varieties by explore effective disease-resistant genes of host and study pathogenic mechanisms of pathogens.There is provide a theoretical basis for disease prevention and management control that explain the epidemic law of wheat stripe rust disease by the traced of diseases inoculum in the occurrence year.In addition,there are understand the disease resistance and find out new resistance genes by the identification disease resistance of commercial wheat.Moreover,in order to explain pathogenic mechanism and mutation mechanism of pathogen which we can build a high-quality genome.Then,those will be able to greatly shorten the breeding cycle.In 2017,wheat stripe rust broke out in China,and the disease epidemic in Hubei and Huang-Huai-Hai region.However,the disease incidence on autumn wheat at the seedling stage in northwestern wheat planting areas such as Gansu and Shaanxi were the lowest in the past 10 years.In order to explain the pathogen source of wheat stripe rust in Hubei province,and identify the disease resistant varieties in the Huang-Huai-hai wheat area,and budling a complete Pst genomic resource.We did the following:1.We presented a de novo genome of wheat stripe rust race CYR34 which size is82.68 Mb.Include 18 chromosomes,293 contigs,contig N50 = 7.9 Mb,and Busco = 97%.A total of 17095 genes,include 1571 secreted proteins.2.We reported a 110.9 Mb pangenome of Pst.This is the first stripe rust pangenome worldwide.A total of 26071 genes,include 4697 secreted proteins.In addition,we developed 63 SSR markers based on the new pangenome.These markers were distributed in the core sequence of the wheat stripe rust genome.3.We have redefined the Pst inocula origin of the Hubei region.The inocula of northwestern Hubei were come from Gansu,but the southern Hubei were come from Yunnan-Kweichow plateau.Then,the southern Hubei pathogens spread to north Hubei after accumulated on wheat.4.We identified three cultivars as “Xinong 889”,“Langyan 43”,and “Shaanmai 139”can resist three races(CYR32,CYR33,and CYR34)at all the stages in the Huang-HuaiHai region.And no cultivar has Yr5 or Yr15 gene in this region.Those results are useful to strengthen for control the stripe rust disease management in China.