EVOLUTIONARY IMPLICATIONS OF SELF-COMPATIBILITY AND REPRODUCTIVE FITNESS IN THE APOMICTIC RANUNCULUS AURICOMUS POLYPLOID COMPLEX (RANUNCULACEAE).
Uniparental reproduction has often been regarded as advantageous for colonization. In pseudogamous a pomicts, reproduction via single individuals requires self-pollination and consequently self-compatibility (SC) for production of viable seeds. SC and reproductive fitness have been studied in diploid and polyploid taxa of the Ranunculus auricomus complex via pollinator exclusion tests, assessment of seed set, and germination rates. Reproductive fitness of sexuals exceeds that of apomicts and of F(1) hybrids but may fluctuate more strongly between years than is the case in apomicts. Diploid sexual taxa and also their F(1) hybrids are completely self-incompatible (SI). Auto-polyploid sexual cytotypes are also predominantly SI, which may have restricted their range expansion. The observed breakdown of SI in the rather widespread allohexaploid apomicts may be explained by initial partial SC inherited from semi-self-compatible ancestors and strong selection for SC genotypes. It is concluded that higher reproductive fitness of sexuals may help to maintain sexual populations when cross-pollination is available, whereas SC in apomicts may be advantageous in temporally and spatially unstable environments and also for colonization events. Results suggest that SC in connection with pseudogamous apomixis is an important factor for the observed distribution pattern of geographical parthenogenesis.
Hörandl
Elvira
E
Department of Systematic and Evolutionary Botany, University of Vienna, Rennweg 14, A-1030 Vienna, Austria.
Mol Ecol. 1999 Dec;8(12):2127-32
10632863
Evolution. 2000 Apr;54(2):337-51
10937212
Trends Ecol Evol. 2005 Sep;20(9):495-502
16701426
Bot J Linn Soc. 1989 Apr;99(4):365-376
32327810
Evolution. 1967 Dec;21(4):853-856
28563079
Evolution. 1985 Jan;39(1):24-40
28563655
Am J Bot. 2007 Sep;94(9):1527-33
21636519
Philos Trans R Soc Lond B Biol Sci. 2003 Jun 29;358(1434):1071-84
12831473
Plant Ecol Divers. 2008 Nov 1;1(2):309-320
20936092
New Phytol. 2004 Jun;162(3):803-811
33873757
Mol Phylogenet Evol. 2005 Aug;36(2):305-27
15955512
New Phytol. 2007;173(2):231-49
17204072
Mol Ecol. 2006 Apr;15(4):897-910
16599955
Heredity (Edinb). 1999 Dec;83 ( Pt 6):707-14
10651915
Mol Biotechnol. 2003 Oct;25(2):149-84
14526125
Evolution. 1998 Jun;52(3):657-668
28565251
Am J Bot. 2004 May;91(5):656-63
21653420
Philos Trans R Soc Lond B Biol Sci. 2003 Jun 29;358(1434):1095-103
12831475
New Phytol. 2005 Nov;168(2):475-86
16219086
Philos Trans R Soc Lond B Biol Sci. 2003 Jun 29;358(1434):1113-21
12831477
Genetics. 2006 Sep;174(1):387-98
16783024
Experientia Suppl. 1987;55:197-217
2961597
New Phytol. 2006;171(1):223-36
16771996
New Phytol. 2006;171(3):525-38
16866956