Fig. 1. Development of population segregating for scs^ti (species cytoplasm specific) genes derived from T. timophevii (Simons et al., 2003). An euplasmic line homozygous for scs^ti was crossed to a chromosomal substitution line [LDN(Dic 1A)]. The resulting F₁ was selfed, producing three genotypes in the F₂ generation. The (d) is indicative of a durum cytoplasm.