Rye Chromosome Composition And Kernel Characters In Different Hexaploid Triticales

The R/D substitutions was studied through Giemsa banding and their correlations with kernel characters determined in 64 hexaptoid spring triticale strains/varieties. Karyotypic analysis revealed that 15 strains had full complement of rye chromosomes, while others had only replacements of one (in 35 strains) or two pairs of rye chromosomes. Preferential R/D substitutions were noticed with chromosome 2R being replaced in most cases, followed by 5R and 4R/7R. In none of the strains studied chromosome IR was replaced. Triticale strains with 4R/7R substitution exhibited lower degree of kernel shrivelling, with higher values for test weight, 100-kernel weight and volume of water displaced by 100-kernels. But 2R, 3R, or 5R replacements resulted in high kernel shrivelling. Any two of these substitutions present together in one triticale, had cumulative effect. The 2R/2D substitution lines exhibited higher seed set, whereas 4R/4D substitution resulted in medium seed set. The seed set was considerably high when both 2R/2D and 4R/4D occurred together. Seed set was low when 3R and 5R were substituted alone or together.