Computer Simulation Studies Comparing Pedigree, Bulk, and Single Seed Descent Selection in Self Pollinated Populations1

Abstract

Computer simulation was used to compare breeding progress under self fertilization with pedigree or mass selection, single seed descent (SSD) and combinations of early generation pedigree or mass selection with SSD. Pedigree selection was the most effective selection method at high (75%) and moderate (50%) heritabilities. At low (25%) and very low (10%) heritabilities, mass selection and SSD respectively yielded the best single F 6 line. Early generation pedigree selection to F 4 followed by SSD was not significantly different from pedigree selection alone at all heritabilities simulated. SSD offers greatest benefits in situations where simultaneous selection is required for several characteristics under different heritabilities. SSD alone or in combination with mass selection retained greater genetic variability for line selection in F 6 . Pedigree or mass selection for highly heritable characters in early generations (F 2 and F 3 ) followed by SSD and F 6 selection on the basis of line performance for characters of low heritability would appear to maximize progress for most breeding situations.