Chromosomal FISH Analysis Of New Germplasm From Triticale CT775/81 × Triticum-Agropyron PSR3628

The phenotypic investigation and sequential GISH-FISH technique were adopted to understand the number,existing form and structural characteristics of alien rye and Agropyron chromosomes,and genetic composition of the BC₁F₃ and BC₁F₄ strains from Triticale CT775/81×Triticum-Agropyron PSR3628 in the present study.The main results were as follows:Chromosomal sequential GISH-FISH analyses of CT775/81 Triticale?female parent?and PSR3628 Triticum-Agropyron?male parent?were established by using genomic DNA,pAs1?red?and pSc119.2?green?probes.CT775/81 triticale contained42 chromosomes,including 14 rye chromosomes,which genetic composition was AABBRR,and a stable hexaploid Triticale.The probe pSc119.2 had abundant signals on the B and R genomes,especially the R chromosomes.The probe pAs1 had richer signals on the A genome than other genomes.These two probes could distinguish each chromosome in CT775/81 Triticale.Triticum-Agropyron PSR3628 was an octoploid derived from distant cross between wheat and Agropyron.It contained 56chromosomes,including 9 pairs of whole chromosomes from Agropyron.Comparing the FISH signals of Triticale CT775/81 and Triticum-Agropyron PSR3628 to those of Chinese spring wheat,etc,it was found that there were some differences in the pAs1and pSc119.2 signals of some chromosomes.The reason might be due to the introgression of alien chromosomes,which resulted in changes of chromosomal structure in the A,B,and D genomes.Sequential GISH-FISH analysis was used to accurately identify the chromosomal composition,the alien chromosomal number and genetic characteristics in the BC₁F₃and BC₁F₄ strains?A1 derivative lines?.A1 derivative lines were divided into 4 types,which were derivative line I,II,III and IV,respectively.Derivative line I consisted of42 translocation lines containing one or two 2RS/2AgL chromosomes,such as A1-25andA1-41lines,whichchromosomalcompositionwere2n=42=AB+12-13I_R+1-2I_2RS/2AgL.Derivative line II included 22 alien addition lines of 3D,5D,6D and 7D chromosomes,respectively,such as A1-34 line?5D disomic addition line?.Derivative line III consisted of 9 alien addition lines with Agropyron 1Ag,3Ag and 4Ag chromosomes,such as A1-45 line?trisomic alien addition line of 1Ag?.Derivative line IV included 9 complex additions with D and Agropyron chromosomes,such as A1-14(multiple alien additions of II_7D and I_1Ag).The main phenotypic traits and segregation characteristics of the BC₁F₃ and BC₁F₄ strains were investigated.The number of grains per panicle of A1-7,A1-13 and A1-62 lines,etc.had super-parent advantage.A1 derived lines showed immunity to wheat powdery mildew,immunity or near immunity to leaf stripe rusts.A1-4,A1-40and A1-67 lines were immunity to head blight,and other most strains showed high resistance,except three susceptibility strains.The lines A1-4,A1-13,A1-14,A1-17,A1-40,A1-47,A1-62,A1-67,A1-75,A1-81 and A1-92 were resistance to ear sprouting.The plant height of the BC₁F₃ and BC₁F₄ strains ranged from 91.17 cm to181.1 cm.The plant height of most strains ranged between two parents?110 cm-140cm?,and the coefficient of variation was 13.46%.The main phenotypes of BC₁F₃ and BC₁F₄ strains were comprehensively evaluated by rank sum ratio statistics method,and performance of A1-1,A-16,A-17,A-41,A-71 and A-72 lines were good.In short,the chromosome composition,important phenotypic features were understood in the progeny in this study,which would widen wheat genetic background,and provide new germplasm for wheat genetics and breeding.