Genetic analysis of karnal bunt resistance in 14 Mexican bread-wheat genotypes uri icon

abstract

  • Fourteen Mexican genotypes of bread wheat (Triticum aestivum L.) with good to moderate levels of resistance to Karnal bunt (Tilletia indica (Mitra)) were crossed with the highly susceptible cultivar WL711 to determine the genetic basis of resistance. The parents, F-1, F-2 and backcross populations of the 14 crosses were evaluated under artificial epiphytotic conditions during the 1993-94 season for Karnal bunt resistance. The F-1 data suggested that the resistance was dominant to partially dominant over susceptibility. The chi(2) analysis of the segregation ratios in the F-2 and backcross generations indicated that the resistance in the wheat genotypes Luan, Attila, Vee# 7/Bow, Star, Weaver, Milan, Sasia and Turacio/Chil is controlled by two genes. The resistance in genotypes Cettia, Irena, Turaco, Opata, Picus, and Yaco was found to be conditioned by a single dominant gene. The genotypes with two genes for resistance expressed a higher level of resistance than those with a single gene and, therefore, are better sources of resistance to Karnal bunt.

publication date

  • 1995
  • 1995