|Guzman, P - IOWA STATE UNIVERSITY|
Submitted to: American Society of Agronomy Meetings
Publication Type: Abstract Only
Publication Acceptance Date: October 27, 1998
Publication Date: N/A
Technical Abstract: There is little empirical information available in plants on the effect of effective population size (Ne) and genetic drift on genetic variability. The objective of this study was to determine the effect of four effective population sizes (5, 10, 20, 30) on genetic variability after five cycles of S1 recurrent selection in the BS11 maize population. One hundred-thirty yBS11 C4 S1 lines from each Ne and 100 BS11 CO S1 lines were top-crossed to BS11 CO. The resulting half-sib progenies were evaluated at five environments in a replication within sets randomized incomplete block design. Average yield ranked 10 > 30 > 5 > 20 > CO but no significant differences were obtain for 5 vs. 10, 20, 30 and for 20 vs. 30. Highly additive genetic variance for yield ranked 5 > 20 > 30 and for 10 vs. 20, 30. The genetic variance and additive genetic variance for yield ranked 5 > 20 > 30 > 10 and heritability was highest for Ne = 20 but no significant differences were obtained among Nes. The results suggest little to no advantage of using larger Nes to maintain or increase genetic variability for short-term recurrent selection.