GENETIC VARIATION OF RESISTANCE AGAINST Puccinia triticina E. IN DURUM WHEATS FROM OAXACA, MÉXICO

Abstract

Land races of durum wheat (Triticum turgidum var durum), called ‘ventureros’, collected in the Oaxaca state of México, showed resistance to durum leaf rust (Puccinia triticina E.) race BBG/BN that affects mainly durum wheats. Four of these collections were crossed to the susceptible durum wheat cultivars ‘Altar C84’ and ‘Atil C2001’, in order to determine the genetics of the resistance to leaf rust in their offspring. The collections resulted genetically heterogeneous. Consequently, their response to resistance depended on the plant used as parent. In the collections ‘CWI52201’ and ‘CWI52271’ two cases of resistance were found: one conferred by a dominant gene and one conferred by two duplicated epistatic recessive genes; in the last one and in most crosses the resistance was conferred by two dominant genes; in the rest of the crosses resistances was due to two duplicated recessive genes. The same result regarding inheritance of resistance was found in collections ‘CWI52274’ and ’CWI52345’, except that conferred by two duplicate recessive genes.