1.

Question : List any two strategy adopted by bisexual flowers to prevent self-pollination.

Answer»

Solution :Dichogamy: In bisexual flowers anthers and STIGMAS mature at different times, thus checking self-pollination. It is of two types.
(1) Protandry:
The stamens mature earlier than the stigmas of the flowers.
Examples: Helianthus and Clerodendrum.
Protogyny:
The stigmas mature earlier than the stamens of the FLOWER.
Examples: Scrophularia nodosa and Aristolochia bracteata.
Self sterility/ Self-incompatibility :
In some plants, when the pollen granin of a flower reaches the stigma of the same, it is unable to germinate or prevented to germinate on its own stigma.
Examples: Abutilon, Passiflora. It is a GENETIC MECHANISM.


Discussion

No Comment Found