NULLISOMIC AND MONOSOMIC ANALYSES OF GENES CONTROLLING LEAF PEROXIDASES IN OATS

Abstract

Monosomics derived from oat cultivars 'Cherokee' (M monosomics) and 'Kanota' (MK monosomics) were used in an attempt to locate gene Px-5a and its allele Px-Sb that control leaf peroxidase bands F (fast) and M (median), respectively, and an independent gene, Px-6a, also controlling band M. M monosomics have band M, and MK monosomics have bands F and M. Nullisomic and monosomic analyses revealed that monosomic MK7 gave a peroxidase banding pattern consistently different from other MK monosomics. Monosomic progeny of MK7 had F and M bands, but nullisomic progeny had only the F band. Monosomic F1 hybrids between MK7 and Columbia (null) and MK7 and Garton 784 had only band F. These results suggested that Px-6a, controlling leaf peroxidase band M, was located on the monosome of MK7, and Px-5a and its allele, Px-5b, must be on a different chromosome. The monosome in MK7 is a SM chromosome.