Oat crown rust race differentiation: replacement of the standard differential varieties with a new set of single resistance gene lines derived from Avena sterilis

Abstract

A review of the physiologic races of oat crown rust, Puccinia coronata f. sp. avenae, isolated in surveys since 1967 indicated a continuing trend toward increased virulence on the standard differential varieties of oats, Avena sativa. Because of this trend and because the inheritance and interrelationships of resistances in the standard differential set are not completely known, a new set of oat crown rust differentials has been introduced. The new set comprises 10 near-isogenic lines of the common oat variety 'Pendek,' into which single resistance genes from Avena sterilis had been transferred. A system of race nomenclature which reflects the pattern of virulence on the new set is proposed.