Study On The Introduction Of Chromosomes Of Thinopyrum Elongatum Into Wheat Background

Thinopyrum elongatum is an important wild relative of wheat.It belongs to the tertiary genetic source of wheat.It has large traits,many flowers,drought tolerance,cold resistance,salt tolerance,strong growth potential and many other excellent traits that wheat does not possess.It is one of the most valuable exogenous gene donors in wheat genetic improvement.The addition of additional lines,substitution lines and translocation lines through the distant hybridization of wheat and Th.elongatum is an important way to utilize the excellent characteristics of Th,elongatum.At present,in the context of common wheat,a complete set of common wheat-Th.elongatum addition lines and substitution lines have been created,but there is not yet a complete set of durum wheat-Th.elongatum addition lines and substitution lines.The aim of this study was to introduce the chromosomes of Th.elongatum into the wheat background,and to cultivate the durum wheat-Th.elongatum and the common wheat-Th.elongatum translocation lines.The specific results are as follows:(1)A variety of identification methods were used to select the 2E and 4E monomer addition lines of durum wheat-Th.elongatum from the progeny population of durum wheat Langdon(AABB)and allohexaploid wheat line 8801(AABBEE).Disomic addition lines were not found in the progenies of self-crossing of the two additive lines for three consecutive years In the meiosis of pollen mother cells of positive individuals in the two additional lines,chromosome segregation lagged behind and micronuclei were observed,which occurred in the later stages Ⅰ,Ⅱ and Ⅱ and tetrad stages.(2)Two addition lines were hybridized with durum wheat,and their progenies were amplified by PCR using 2E and 4E chromosome markers.The transmission rates of 2E and 4E chromosomes in durum wheat background were 4.41%and 2.17%respectively through male gametes,but no 2E and 4E chromosomes were transmitted through female gametes.(3)After the pollen of 60Co-γ-ray radiation translocation line TW7BS·7EL was mixed with Yangmai 158 to obtain M1,it was identified from the backcross BC1F2 of M1 and Yangmai 158 by 7EL specific molecular marker and genomic in situ hybridization technique.Seven types of translocations carrying the 7EL chromosome fragment of Th elongatum.Based on the different breakpoints of the 7EL chromosomal translocation fragment,48 molecular markers were mapped to different regions of the 7EL chromosome of Th.elongatum.Two years of Fusarium head blight(FHB)resistance identification of seven types of translocations indicated that TL1,TL2 and TL5 had higher FHB resistance levels similar to that of Sumai 3,and fragments of these three translocations were initially considered.It contained the anti-scarial disease gene-while TL3,TL4 and TL6 showed a moderate sensation,indicating that there were no anti-chick gene in the three translocation fragments.