Inheritance of virulence of Ustilago tritici on the differential cultivars Carma, Red Bobs, and a derivative of the cross Thatcher × Regent

Abstract

A cross between races T2 and T5 of Ustilago tritici was used to study the inheritance of virulence on three differential cultivars of spring wheat: Carma, Red Bobs, and a derivative of the cross Thatcher × Regent. Virulence on each of the cultivars was conditioned by a recessive gene. Gene Utv3 is responsible for virulence on cv. Carma, Utv4 for that on cv. Thatcher × cv. Regent, and virulence on cv. Red Bobs appears to be conditioned by the previously identified gene Utv1. These genes segregate independently from each other and from the gene for mating type.