What is self-incompatibility? Why does self-pollination not lead to seed formation in self-incompatible species?
Solution and Explanation
Self-incompatibility is a genetic mechanism in angiosperms that prevents self-pollination. It develop genetic incompatibility between individuals of the same species or between individuals of different species. The plants which exhibit this phenomenon have the ability to prevent germination of pollen grains and thus, prevent the growth of the pollen tube on the stigma of the flower. This prevents the fusion of the gametes along with the development of the embryo. As a result, no seed formation take place.
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Notes on sexual reproduction in flowering plants
Concepts Used:
Pollination and Double Fertilization
Pollination is defined as the pre-fertilization event or process, where pollen grains from another are transferred to the stigma of a flower.
Double fertilization is a complex process that involves the fusion of one female gametophyte with two male gametes.
Types of Pollination:
All plants having flowers completely rely on the pollination method for reproduction. There are 2 types of pollination –
- Self Pollination
- Cross-Pollination
The end products of double fertilization are:
- Diploid Zygote
- Primary Endosperm Nucleus