Genetic analysis of grain mould resistance in coloured sorghum genotypes uri icon

abstract

  • Grain moulds are a major constraint to sorghum production and to adoption of improved cultivars in many tropicalareas. Information on the inheritance of grain mould reaction is required to facilitate breeding of resistant cultivars.The genetic control of grain mould reaction was studied in 7 crosses of 2 resistant sorghum genotypes. P1, P2, F1,F2, BC1 and BC2 families of each cross were evaluated under sprinkler irrigation for field grade and threshed gradescores and subjected to generation mean analysis. Frequency distributions for grain mould reaction were derivedand F2 and BC1 segregation ratios were calculated. Grain mould reaction in crosses of coloured grain sorghum wasgenerally controlled by two or three major genes. Resistance to grain moulds was dominant. Significant additivegene effects were also found in all cross/season combinations. Significant dominance effects of similar magnitudeto additive effects were also observed in five out of ten cross/season combinations. Gene interactions varied accordingto the parents with both resistant and susceptible parents contributing major genes. Choice of parents withcomplementary resistance genes and mechanisms of resistance will be critical to the success of resistance breeding

publication date

  • 2000
  • 2000