Molecular Cytological Identification And Transcriptome Analysis Of Wheat-psathyrostachys Huashanica Keng Derived Line With Elongated Glume

Distant cross breeding of wheat is a good way to introduce excellent genes of wheat-related species into common wheat.Psathyrostachys huashanica Keng（2n=2x=14,Ns Ns）is one of the first-class protected plants and wheat-related species in urgent need of protection in China,which comes from the Psathyrostachys of Triticeae of Poaceae.P.huashanica with abundant superior germplasm of early-maturing,dwarf,disease resistance,stress-bearing,belongs to tertiary gene pool of wheat.In this study,a derived line 20JH1155 with elongated glume was screened out which was created by hybridizing heptaploid wheat-P.huashanica H8911（2n=7x=49,AABBDDNs）with durum wheat Trs-372.Methods of cytological observation,in situ hybridization of the genome,fluorescence in situ hybridization,molecular markers,liquid chip detection,transcriptome analysis and marker development were used to analyze this material.The main results are as follows:（1）Molecular cytological genetics analysis of derived line 20JH1155.Morphological observation showed that 20JH1155 had long-glume,combined with larger grains,longer spike and resistance to fusarium head blight than its parents.Cytological identification showed that the derived line 20JH1555 contained 44 chromosomes.Using the genome of P.huasanica as probe for GISH,oligo-p Sc119.2（green）and oligo-p Ta535（red）as probe for FISH,the results showed that 20JH1155 contained all 42 chromosomes of common wheat and 2 chromosomes of P.huashanica and there were some differences in 5A and 7B chromosomes between 20JH1155 and parental wheat 7182.HS-TZ3（green）and HS-TZ4（red）as specific probe for ND-FISH showed that the alien 2 chromosomes were much like3Ns.The results of EST marker,PLUG marker,SCAR marker,molecular cloning and SNP chip showed that the two alien chromosomes of derived line 20JH1155 were 3Ns from P.huashanica.The agronomic traits of F₂ in the offspring population of derived line 20JH1155and Zhou Mai 18 was investigated,and the correlation analysis of agronomic traits showed that the glume length was positively correlated with grain length and thousand kernel weight.In conclusion,20JH1155 is wheat-P.huashanica 3Ns additional line,which can be used as a candidate germplasm resource for wheat glume development research,yield improvement and FHB resistance breeding.（2）Transcriptome analysis and marker development of derived line 20JH1155.Three times of transcriptome samples were performed of 20JH1155 and parental wheat 7182 in the jointing stage,the analysis of differentially expressed genes（DEGs）and weighted gene co-expression network analysis（WGCNA）showed that a total of 3474 genes were identified as potential foreign genes from the transcriptome data analysis of common wheat 7182 and20JH1155.K-means analysis and cluster analysis of DEGs showed that the alien genes of20JH1155 involved in the material accumulation,carbohydrate metabolism and cell differentiation of wheat spikelet development.Based on WGCNA,27 co-expressed gene modules were constructed.80 functional genes associated with spikelet development and regulating spike traits were screened from MEbrown module that was positively correlated with 20JH1155 and negatively correlated with 7182.Molecular cloning showed that20JH1155 contained Ta VRT-A2 that could regulate spike development.Transcription factor prediction screened 35 candidate genes associated with spikelet development,of which 7were potentially exogenous genes associated with spikelet development.Based on transcriptome data,7 pairs of P.huashanica 3Ns specific molecular markers were developed,which could identify P.huashanica exogenous chromosomes in wheat background.This study provided a reference for the researching the influence of P.huashanica chromosomes on the spike development of common wheat.