How far are we from unravelling self-incompatibility in grasses?
The genetic and physiological mechanisms involved in limiting self-fertilization in angiosperms, referred to as self-incompatibility (SI), have significant effects on population structure and have potential diversification and evolutionary consequences. Up to now, details of the underlying genetic control and physiological basis of SI have been elucidated in two different gametophytic SI (GSI) systems, the S-RNase SI and the Papaver SI systems, and the sporophytic SI (SSI) system (Brassica). In the grass family (Poaceae), which contains all the cereal and major forage crops, SI has been known for half a century to be controlled gametophytically by two multiallelic and independent loci, S and Z. But still none of the gene products for S and Z is known and only limited information on related biochemical responses is available. Here we compare current knowledge of grass SI with that of other well-characterized SI systems and speculate about the relationship between SSI and grass SI. Additionally, we discuss comparative mapping as a tool for the further investigation of grass SI.
Yang
Bicheng
B
Teagasc Crops Research Centre, Oak Park, Carlow, Ireland.|Institute of Grassland and Environmental Research, Aberystwyth, Ceredigion SY23 3EB, UK.|School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
Thorogood
Danny
D
Institute of Grassland and Environmental Research, Aberystwyth, Ceredigion SY23 3EB, UK.
Armstead
Ian
I
Institute of Grassland and Environmental Research, Aberystwyth, Ceredigion SY23 3EB, UK.
Barth
Susanne
S
Teagasc Crops Research Centre, Oak Park, Carlow, Ireland.
D005075:Biological Evolution; D005854:Germ Cells / Q000502:physiology; D007178:Inbreeding; D006109:Poaceae / Q000235:genetics / Q000502:physiology*