and their F1, F2 and BC1 populations were established. In the established populations, resistance differences were significant (P>0.05) for NCEBR2 × NC8413 and NC84173 × NCEBR4 parents, F1 and BC1. However, no significance (P>0.05) was obtained in their F2 population to early blight pathogen. The data from these populations revealed that early blight resistance in NCEBR2 and NCEBR4 was quantitatively controlled by more than one gene or quantitative trait locus under controlled glasshouse environment.