Genomic selection in XXXX : optimum allocation of test resources and comparison of breeding strategies for line and hybrid breeding.

@entity3505 @entity5555
KEY MESSAGE: The implementation of @entity5555 in breeding programs can be recommended for hybrid and line breeding in @entity3505 . High prediction accuracies from @entity5555 ( @entity5555 ) were reported for grain yield in @entity3505 asking for the elaboration of efficient breeding strategies applying @entity5555 . Our objectives were therefore, (1) to optimize the number of lines, locations and testers in different multi-stage breeding strategies with and without @entity5555 , (2) to elaborate the most efficient breeding strategy based on the selection gain and its standard deviation, and (3) to investigate the potential of @entity5555 to improve the relative efficiency of hybrid versus line breeding in @entity3505 . We used the open source software package "selectiongain" to optimize the allocation of resources in different breeding strategies by predicting the expected selection gain for a fixed budget. Classical two-stage phenotypic selection was compared with three @entity5555 breeding strategies for line and hybrid breeding in @entity3505 . The ranking of the alternative breeding strategies varied largely in dependence of the @entity5555 prediction accuracy. Fast-track breeding strategies based solely on @entity5555 were only advantageous for high @entity5555 prediction accuracies that is >0.50 and >0.65 for hybrid and line breeding, respectively. However, a @entity5555 prediction accuracy across breeding cycles of 0.3 or even less must be assumed as realistic for grain yield in @entity3505 . For this low @entity5555 prediction accuracy, the use of @entity5555 is advantageous for line but especially for hybrid breeding in @entity3505 . Furthermore, the use of @entity5555 in hybrid @entity3505 breeding increased the relative efficiency of hybrid versus line breeding and, thus, might be an important pillar for the establishment of hybrid @entity3505 .
