|
Self-incompatibility is one strategy that evolved with the flowering plants to maintain genetic diversity in a species population and avoid inbreeding. It is not universal in the flowering plants, where a number of other morphological and/or physiological mechanisms are employed that achieve the same purpose. Indeed, a great many species are self-compatible.
Flowering plants that have hermaphroditic or perfect flowers (that is, have both male (anther) and female (pistil) reproductive organs) may be self-incompatabile to prevent self-fertilization. This self-incompatibility limits inbreeding and promotes out-breeding. The stigma of the pistil can recognise and reject self-pollen or pollen from very closely related individuals (clones) so that only non-self pollen grains achieve fertilization.
There are two types of self-incompatibility: gametophytic and sporophytic
- Gametophytic self-incompatibility is the most common type found in flowering plants.
- Sporophytic self-incompatibility involves the phenotype of the pollen being determined by the diploid genome of the parent plant.
See also
External links
|
