Department of Genetics, Punjab Agricultural University, Ludhiana 141 004.
1Present address: Division of Genetics, Indian Agricultural Research Institute, New Delhi 100 012, India.
The inheritance of resistance to a pathotype IX05 collected from north western India was studied in three lines of rice B 76, ARC 10464 and CNGS 20083. These lines were crossed to a susceptible cultivar Taichung Native 1 to generate F1, F2 and F3 generations. The reaction of F1 and segregation pattern in F2 and F3 generations suggest that the resistance of B 76 and CNGS 20083 was conditioned by a dominant and a recessive gene respectively. Breeding lines ARC 10464 carried two independently inherited dominant genes. Since the F2 generations obtained from intercrosses of these three lines segregated for susceptible plants it is concluded that B 76, ARC 10464 and CNGS 20083 have different genes conferring resistance to pathotype IXC5 of X. c. pv. oryzae.
X. c. pv. oryzae, resistance, pathotype
