Comparative efficiency of pedigree, modified bulk and single seed descent breeding methods of selection for developing high-yielding lines in rice (Oryza sativa L.) under aerobic condition

The knowledge about the relative efficiency of the different breeding methods may greatly help the plant breeder in selecting a better method to be adopted in a particular crop. In the present experiment, the comparative efficiency of three selection methods, viz., pedigree, modified bulk and single seed descent (SSD) were assessed in F₃, F₄, F₅ and F₆ generations of a cross combination Moroberekan/IR20 of rice. Bulk population showed superiority over pedigree for grain yield, panicle length, number of panicles, number of tillers and harvest index in F₃ generation. Pedigree method was found to be superior over bulk and SSD for grain yield per plant in F₄ and F₅ generations. In the three breeding methods, mean values of grain yield showed directional shift across the generations. In F₆ generation, the pedigree-derived lines showed higher superiority over mean value than lines derived from SSD and modified bulk for grain yield, number of panicles and harvest index. No significant differences existed between pedigree and modified bulk-derived F₆ lines for grain yield and harvest index. Inter-generation correlation coefficients were significant and positive between all the generations for grain yield, number of tillers and number of panicles. Significant and positive correlations were observed between these three characters across generations supporting the intergeneration correlation results. Visual selection based on the number of tillers and number of panicles per plant was very effective for increasing yield in bulk and pedigree methods.