EVALUATION OF GENETIC POTENTIAL OF INTRAHIRSUTUM F2 POPULATIONS THROUGH LINE × TESTER ANALYSIS
M. J. Baloch1*, Q. A. Bughio1, A. W. Baloch1, W. A. Jatoi1, M. A. Arain1, A. Baloch1 and F. M. Halo2
1Department of Plant Breeding and Genetics, Sindh Agriculture University, Tandojam, Pakistan, 2Cotton Section, Agriculture Research Institute, Tandojam
*Corresponding author’s email: firstname.lastname@example.org
The objectives of research were to estimate the GCA, SCA and heritability for yield and fiber traits in F2 populations. Four lines were crossed with 4 testers and 16 F2 populations were obtained for evaluation for determining combining ability and heritability estimates. The trials were laid-out in RCBD with four replications during 2013 and 2014. Combined analysis revealed that genotypes performed differently over the years; however genotype × year interactions were non-significant for majority of the traits. Mean squares for lines and testers were significant, indicating the importance of GCA with additive genes while lines × tester interactions implied the importance of SCA with dominant genes. The lines, Sadori and CIM-573 and testers FH-113 and IR-1524 were good general combiners hence showed their suitability for hybridization and selection programmes. Degree of dominance was higher than unity which suggested the prevalence of dominant genes. The heritability estimates were generally low because of greater portion of dominant variances.
Key words: Combining ability; heritability; upland cotton.