PERFORMANCE OF S3 WHEAT INBRED LINES DERIVED FROM POPULATIONS IMPROVED BY RECURRENT SELECTION

Abstract

The effect of a recurrent selection procedure for improving grain yield in a wheat (Triticum aestivum L.) population was evaluated. The recurrent selection scheme incorporated S₀ single-plant selection, S₁ combined selection, S₂ family selection and selected S² lines recombination. Genetic progress from selection was estimated by field testing of 10 selected S₃ lines from each cycles (C₀, C₁, C₂, and C₃). Selection gain for grain yield was 14.4 % per selection cycle, equivalent to 217 kg ha^-1 year^-1. Yield improvement of 414 kg ha^-1 from C₀ to C₁, 215 kg ha_-1 from C₁ to C₂ and 739 kg ha^-1 from C₂ to C₃, was mainly associated to a significant increases in the number of spikes per square meter, spikelets per spike, grain filling rate, and maturity date (110 days in C₀ to 113 days in C₃). In C₃, broad-sense heritability and genotypic variance for grain yield remained high, suggesting further gains in future selection cycles.