HYBRID CHLOROSIS IN WHEAT X RYE CROSSES

Fourteen accessions of rye when crossed to Triticum aestivum cv. C 306 (Ne1ne2ch1Ch2) yielded chlorotic F1 hybrids and six accessions involv ed in hybrid combination with the same tester produced normal F1 hybri d plants. Two rye accessions, namely, EC 179188 and EC 143825 when cro ssed to the wheat lines HD 2329 (ne1Ne2ch1Ch2) and NI 5439 (ne1ne2ch1C h2) also produced chlorosis. The hybrids between T. macha and two rye accessions produced normal plants. Variable degrees of chlorosis were observed among different wheat x rye F1 hybrids. It is suggested that the rye accessions producing chlorosis in combination with wheat cvs. C 306, HD 2329 and NI 5439 (all Ch2-carriers) carry one of the complem entary genes for chlorosis. Gene symbol Chr1 is proposed for the chlor osis gene of rye.