Inheritance of Resistance in Peanut to Mixed Infections of Groundnut Rosette Virus (GRV) and Groundnut Rosette Assistor Virus and a Single Infection of GRV

Abstract

Inheritance of resistance to the green form of groundnut rosette was studied in two ways—aphid inoculation in the field with a mixed culture of groundnut rosette virus (GRV) (plus its satellite RNA) and groundnut rosette assistor virus (GRAV) and mechanical inoculation in the greenhouse with GRV (plus its satellite RNA). Crosses were made with two resistant and six susceptible genotypes in a diallel test. In most crosses, the resistance was conditioned by two recessive genes. Furthermore, results were similar both with mixed infections and the single GRV infection, thus providing direct evidence that genetic control of resistance is to GRV and not to GRAV. In the RMP 12 × M1204.78I cross (and its reciprocal), F2 progeny segregated 1:3 susceptible/resistant. Mechanical inoculation with GRV provided an acceptable and rapid procedure to screen segregating populations for resistance to the virus