Genotypic and Phenotypic Characterization of Two Triticum aestivum L.—Dasypyrum villosum Translocations Lines in the Same Wheat Genetic Background

A wheat 660K chip was used to genotype two wheat-Dasypyrum villosum 6V#4S.6DL and 6V#2S.6AL translocation lines (A303 and B303) and their common wheat recurrent parent Wan7107. The results showed that these three lines have similar characteristics of base composition except for the translocation chromosomes. The alien translocation chromosomes have fewer homozygous and more heterozygous genotypes with more invalid probes. Distributions of SNPs between the translocation lines and Wan7107 were mainly dense on the regions of 6AS or 6DS as expected, but unexpectedly also on near the telomere of 2BS, and some regions of other wheat chromosomes. Meanwhile, the translocation lines A303 and B303 have 99.44% and 98.81% identical genotypes to Wan7107, respectively. Under the same genetic background, A303 and B303 showed different reactions to Blumeria graminis f. sp. tritici (Bgt) strains of powdery mildew. Both translocation lines have higher grain weight and plant height, and B303 has fewer spikelets compared to Wan7107. These results provide us a new insight into the genomic variation between the backcross generation plant and the recurrent parent, which is valuable information for understanding the relationship between wheat and the 6VS chromosome of D. villosum as well as the application potential of the alien chromosome arms.