Sex-ratio evolution in nuclear-cytoplasmic gynodioecy when restoration is a threshold trait.
Gynodioecious plant species, which have populations consisting of female and hermaphrodite individuals, usually have complex sex determination involving cytoplasmic male sterility (CMS) alleles interacting with nuclear restorers of fertility. In response to recent evidence, we present a model of sex-ratio evolution in which restoration of male fertility is a threshold trait. We find that females are maintained at low frequencies for all biologically relevant parameter values. Furthermore, this model predicts periodically high female frequencies (>50%) under conditions of lower female seed fecundity advantages (compensation, x = 5%) and pleiotropic fitness effects associated with restorers of fertility (costs of restoration, y = 20%) than in other models. This model explains the maintenance of females in species that have previously experienced invasions of CMS alleles and the evolution of multiple restorers. Sensitivity of the model to small changes in cost and compensation values and to initial conditions may explain why populations of the same species vary widely for sex ratio.
Bailey
Maia F
MF
Department of Biology, Indiana University, Bloomington, IN 47405, USA. maia.bailey@gmail.com
Delph
Lynda F
LF
D005075:Biological Evolution; D001947:Breeding; D002467:Cell Nucleus / Q000235:genetics; D003593:Cytoplasm / Q000235:genetics; D017343:Genes, Plant; D008957:Models, Genetic; D018521:Plant Physiological Phenomena; D010944:Plants / Q000235:genetics*; D012098:Reproduction / Q000235:genetics
J Hered. 1999 May-Jun;90(3):386-93
10355123
Am Nat. 2000 Jun;155(6):814-819
10805646
Genetics. 2001 Jun;158(2):833-41
11404344
Heredity (Edinb). 2001 Mar;86(Pt 3):265-76
11488964
Nat Rev Genet. 2002 Jan;3(1):11-21
11823787
Evolution. 2002 Nov;56(11):2178-86
12487348
Evol Dev. 2003 Jan-Feb;5(1):34-9
12492407
Genet Res. 2002 Dec;80(3):187-95
12688657
Am Nat. 2003 May;161(5):762-76
12858283
Mol Ecol. 2004 Aug;13(8):2459-64
15245417
Evolution. 2005 Feb;59(2):287-95
15807415
Heredity (Edinb). 2005 Jul;95(1):50-8
15829984
Proc Biol Sci. 2005 Sep 7;272(1574):1795-802
16096091
Am Nat. 2005 Nov;166(5):592-602
16224724
Trends Ecol Evol. 2007 Jan;22(1):17-24
17028054
J Evol Biol. 2006 Nov;19(6):1995-2005
17040397
Genetics. 1985 Feb;109(2):427-39
17246254
Plant Cell. 1991 Dec;3(12):1349-62
1840901
Am Nat. 1998 Jul;152(1):59-70
18811401
Theor Appl Genet. 1995 Jul;91(1):150-9
24169681
Theor Appl Genet. 1991 Aug;82(2):137-43
24213057
Theor Appl Genet. 1980 Jan;57(1):11-5
24302360
Evolution. 1989 Nov;43(7):1424-1434
28564233
Plant Cell. 1995 Mar;7(3):271-85
7734962
Genetics. 1995 Apr;139(4):1749-58
7789775
Genetics. 1997 Nov;147(3):1367-79
9383077
Genetics. 1998 Nov;150(3):1267-82
9799278