Function of Heterostyly

The occurrence of pollen-size heteromorphism in heterostylous species enables measurement of disassortative (inter-morph) pollen transfer based on the analysis of stigmatic pollen loads. Data obtained from 'pollen flow' studies can be used to evaluate Darwin's cross-promotion hypothesis for the adaptive significance of heterostyly. Ganders (1979) and Lloyd and Webb (1992b) summarized experimental evidence supporting the Darwinian hypothesis, based largely on studies of bee-pollinated species...

Phylogenetic Distribution of SI Systems

It is over a decade since Weller et al. (1995) carried out the first detailed phylogenetic analysis of the distribution of SI systems in angiosperms. Since then there have been significant advances in our understanding of the phylogenetic relationships between the flowering plants (Soltis et al. 1999 Qiu et al. 1999,2005), giving us a far better understanding of the phylogenetic relationships amongst the most basal angiosperm lineages. Studies of the mating systems of basal angiosperms have...

Contents

Part I Evolution and Population Genetics of Self-Incompatibility 1 New Insights on Heterostyly Comparative Biology, Ecology and Genetics 4 1.2 Comparative Biology and Evolutionary History of Heterostyly 6 1.2.1 Phylogeny Reconstruction and Character Evolution 7 1.3 Function and Reproductive Ecology of Heterostyly 10 1.3.1 Function of Heterostyly 10 1.3.2 Floral Morph Ratios and Reproductive Success 12 1.4 Inheritance of Heterostyly and the Supergene Model 14 1.4.1 Inheritance of Distyly and...

Floral Morph Ratios and Reproductive Success

Reproductive success in species with stylar polymorphisms should be sensitive to plant density and the morph composition of local neighbourhoods. To investigate the spatial ecology of mating, Stehlik et al. 2006 mapped the location of floral morphs in N. assoanus populations and determined their female fertility. They found that pollen transfer and mating was context dependent, with the floral morphs responding differently to the density and morph identity of plants in local patches. Studies of...