Question

Does self incompatibility impose any restrictions on autogamy? Give reasons and suggest the method of pollination in such plants.

Answer 1

Self incompatibility and autogamy

The phenomenon in which the pollen from the anther of a flower fails to germinate on the stigma of the same flower is referred to as self incompatibility. This prevents autogamy.

Self incompatibility imposes restrictions on autogamy- reasons

● The stigma has machinery (pollen-pistil interaction) which can recognise an incompatible pollen (sometimes, pollens of the same flower) by chemical interaction governed by genetic mechanisms.
● If an incompatible pollen lands on the stigma of a flower in a plant, the germination of the pollen is rejected (pollen tube formation is not allowed).

Cross pollination

Method of pollination in self incompatible plants is cross pollination,when the stigma of a flower is pollinated with the pollen grains from a flower of another plant.