Selection Procedure Based on Cross and Line Performance
Plant breeders have suggested that breeding progress could be enhanced by first selecting crosses, and then selecting individual lines within these crosses. Evaluation of F1 progenies and early generation bulk populations have been recommended as methods of identifying superior crosses, but have not been widely adopted. The purpose of this note is to propose a method of selection, referred to as cross-line selection, that relies on both cross and line performance when selecting individual lines. The procedure is intended for use at the time of replicated yield testing when each cross is represented by several lines and there are several yield trials. It entails allocation of individual lines of each cross to different trials, so each cross is represented in more than one trial by subsets of lines. Selection of individual lines is done within crosses that have high subset means compared with other crosses. While experiments have not been done to evaluate the procedure, I encourage its use because of its value in identifying high-yielding lines in our breeding program.
Copyright © 1991.