GENETICS OF RESISTANCE OF DURUM WINTER WHEAT TO Puccinia triticina Eriks

Abstract

Among 51 durum winter wheat (T. turgidum var. durum) genotypes, Mirlo 26 and Elinia 48 were resistant to P. triticina race BBG/BPC at the seedling stage. From the progeny of the crosses with the susceptible spring cultivar Atred, it was determined that in Elinia 48 resistance was conferred by a dominant and by a recessive gene, while in Mirlo 26 resistance is provided by a recessive gene. The cross between the two resistant genotypes did not produce susceptible progeny in the F2 or F3 families, suggesting at least one common resistance gene is present in both parents. Mirlo 26 is susceptible to race BBB/BNJ identified in 2008, while Elinia 48 remained resistant. Using this race, it was possible to determine that the recessive gene identified in Mirlo 26 is the gene that both parents have in common. To test these results, the progenies of Mirlo 26 x Elinia 48 cross were inoculated with race BBB/BNJ, virulent to the recessive gene. In both populations F2 and F3 the segregation was 3:1, which corresponds to the segregation of a single dominant gene. As a result of the Winter x Spring crosses, there are now spring durum wheats carrying the dominant gene and lines with the recessive gene.