To determine whether linkage drag had occurred during the breeding of near isogenic lines (NILs) of wheat, 176 lines involving 11 sets of NILs, their recurrent parents and some of their donors were tested for seedling reaction to stem rust (4 races), leaf rust (3 races) and yellow rust (3 races). From the results, six cases were identified in which linkage drag may have played a role. More research is needed to prove clearly that linkage is involved. Nevertheless, the results suggest that linkage drag is a fairly common phenomenon.