COMPARISON OF RECURRENT SELECTION METHODS IN WHEAT: I. DESCRIPTION OF METHODS AND EXPECTED RESPONSE

Abstract

Eleven recurrent selection methods were applied and compared in wheat (Triticum aestivum L.) breeding for grain yield (R). The original population was formed from balanced mixture of seeds from 28 F2 crosses of eight parental lines, where environmental and genetic parameters were estimated with design II of Griffing from the combined analyses of three contrasting environments, and the use of the parameters to compare expected genetic gains (DG). Supposing equal selection intensity, the selection method with greater DG for R per agricultural cycle was that of the S2 families. From the practical point of view of genetic efficiency per cycle and the feasibility in wheat of applying recurrent selection, the method which produced the maximum DG for R in the recombinant population was the alternate selection of selfed lines with S0 individual plant evaluation, with combined selection in S1, and family selection in S2. Selection for spike length increased the expected R by 7 % per selection cycle, compared to direct selection.