Screening And Cytogenetic Identification Of Superior Germplasm Lines Of Wheat-Thinopyrum Intermedium

Thinopyrum intermedium(2n=6x=42,JJJ~SJ~SSt St or E~eE~eE~bE~bSt St)is one of the important relatives of wheat.It has excellent disease resistance,cold resistance,drought resistance,salt and alkali resistance,etc.,and has strong environmental adaptability.ability.Using distant hybridization to introduce the excellent genes of Thinopyrum intermedium into common wheat can create new variant types of wheat,broaden the genetic basis of wheat,improve the adaptability of wheat in various aspects,and improve the quality of wheat.It is an important resource for innovative wheat breeding.one of the directions.In this study,morphological observation and GISH,FISH,SDS-PAGE and other techniques were used to analyze the agronomic traits,chromosome karyotype,and HMW-GS composition of 14 Trititrigia derived lines and parental materials,and screened out comprehensive The derived line materials of Trititrigia with excellent traits and stable genetic basis provide a basis for its subsequent effective utilization.The main results are as follows:(1)The characteristics of agronomic traits of 14 Trititrigia germplasm lines were clarified,among which 7 germplasms W281,W282,W283,W284,W287,W288 and W290of Trititrigia derived lines performed well in the field and could be used as excellent germplasm for genetic improvement of wheat.(2)Using molecular cytogenetics techniques,it was confirmed that Trititrigia W277 and W279 were wheat-Thinopyrum intermedium disomed addition lines,and it was deduced that both of them had added a pair of 1St-J~S exogenous chromosomes.There were differences in FISH band patterns between the two,which were mainly distributed on chromosomes 3A,4A,2B,and 7B,which led to differences in main agronomic characters such as plant height and spike length.Therefore,it shows that they are different disomed addition lines.The results showed that 6 Trititrigia W285,W286,W287,W288,W289 and W290 were wheat-Thinopyrum intermedium introgression lines.Although there was no obvious exogenous signal in GISH,there were differences in the FISH karyotypes of both parents,presumably due to the introgression of exogenous chromosome fragments in Thinopyrum intermedium.The remaining 6 germplasm W278,W280,W281,W282,W283,W284 are 1RS·1BL translocation lines.(3)The HMW-GS compositions of different germplasm materials were analyzed by SDS-PAGE,among which the HMW-GS compositions of germplasm W278 and W280 were(1,14+15,5+10),and the HMW-GS compositions of W277,W279 and W281 were(1,7+9,2+12).Among them,the five subunits of W278 and W280 are high-quality subunits,which can be used as germplasm resources carrying high-quality HMW-GS for wheat breeding to improve wheat quality.