Effectiveness of selection response on F3 and F4 generations for grain yield and yield attributing traits in aromatic rice (Oryza sativa L.)

Abstract

Genetic variability present in the F2 generation originating from ten crosses of rice genotypes, selection was practiced for high 
grain yield. Expected selection response was estimated in F3 generations and compared with F2 generation. Similar selection 
practices were made in F3 generation and selection response was estimated in F4 generation. F3 generation showed significant 
positive selection response for grain yield, number of panicles per plant, plant height and days to 50 % flowering thus indicating 
the effectiveness of selection for these traits. Grain yield showed non-significant response in F2 generation which indicates 
straight selection for this trait during early generation may not be effective. F4 generation showed significant positive selection 
response for the entire traits viz. grain yield, number of panicles per plant, plant height, number of grains per panicle and days to 
50 % flowering this indicating the effectiveness of selection for these traits in F3 or latter generation.  The regression coefficient 
between F2 and F3 generation and F3 and F4 generations was significant for all the traits. However, selection for plant height, 
number of panicles per plant and days to 50 % flowering could be made in early segregating generation while grain yield per 
plant and number of grains per panicle were effective for selection in latter generation.