GENE ACTION AND GENES THAT CONFER LEAF RUST RESISTANCE IN DURUM WHEAT

Abstract

Leaf rust, caused for the fungus Puccnia triticina E. is a disease that, when present, generates loses of up to 100 % in the grain yield of durum wheat (Triticum turgidum ssp. durum L.). As a measure of genetic protection in the pyramidal construction of new resistant genotypes, it is necessary to identify the number of genes involved and their gene action in germplasm with resistance to this disease. For this purpose, during the Autumn-Winter 2017- 2018 crop cycle, the susceptible parents Atred#1 and Atred#2 were crossed with the resistant lines of durum wheat landraces from Ethiopia WC-2 no. 100, DW-K2 no. 47, Oda, 2000/01 population FR. no. 43, 2000/01 population 37- 30 BDI no. 63 and 2000/01 population 37-30 BDI no. 12. The filial generations of the crosses were obtained alternately at CIMMYT-Batan, State of Mexico and CIMMYT-CENEB, Ciudad Obregon, Sonora, until obtaining Families F₃ and F₄ . Based on  segregation analyzes of such families, it was found that in the six Ethiopian lines, resistance to leaf rust is conferred by two dominant genes.