Identification of genetic linkage between male sterility and dwarfness in safflower

Six spontaneous dwarf male sterile (DMS) mutants of about 30 cm mean plant height were identified in safflower accession BLY 1035. The inheritance of male sterility and dwarfness in F₁, F₂ and F₃ progenies of DMS crosses suggested that the two characters are governed by different recessive genes in homozygous state. Male sterility and dwarfness are designated by the gene symbols ms₂ and dw respectively. The genetic analysis revealed close linkage between ms₂ and dw genes. Among the crosses, DMS XHUS 282 and DMS x BLY 1035 exhibited complete linkage between the sterility and dwarfing genes. However, the crosses DMS x crv 244 and DMS x Bhima recorded 0.72 ± 0.73% and 7.97 ± 1.98% linkage distances, respectively, between ms₂ and dw. Linkage between the genes for male sterility and dwarfness is reported for the first time, and its usefulness in hybrid seed production is discussed.