In a bisexual flower,if androecium and gynoecium mature at different times,the phenomenon is known as a

When the anthers mature earlier than the stigma of one's own flower,the condition is known as

Given below are two statements.
Statement $I$: Self-incompatibility is a device that prevents outbreeding.
Statement $II$: Self-incompatibility is a genetic mechanism due to which germination of pollen on the stigma of the same flower is inhibited.
In the light of the above two statements,choose the correct answer from the options given below.

Which one of the following usually does $NOT$ promote self-pollination?

The dioecious condition prevents:

Which one of the following favours herkogamy for cross-pollination?