Fig. 3

Trends in genetic gain for IRRI drought released lines and popular checks under three conditions: a non-stress, b drought and c combined conditions. The genetic gain was estimated by regressing the breeding values on the year of origin of genotype, d shows the biplot of the lines selected based on the breeding value for grain yield as an elite core panel. Core panel lines are highlighted in dark red color. The checks and released lines are shown in blue color, and the whole historical collection lines are represented in gray color. The biplot was constructed using the first two principal components obtained from the pedigree-based relationship matrix. The selected lines represent and capture the variability of the whole collection of genotypes and are ideal to form the core panel as a future breeding resource