Abstract
The genes responsible for three types of chlorosis found in hybrids between the Emmer and the Timopheevi group of tetraploid wheats were analyzed by test crosses. The presence of the complementary genes, Cs1 and cs1 in the Emmer group and Cs2s, Cs2m, Cs2w and cs2 in the Timopheevi group were confirmed. The frequency of Cs1 in the Emmer group was very low and none of the wild Triticum dicoccoides strains had Cs1. On the other hand, about half of the strains of the wild Timopheevi, T. araraticum, and all strains of the cultivated T. timopheevi had either Cs2s, Cs2m or Cs2w.
