Plant sexuality

Differences in the breeding system of plants are responsible whether individual plants will self-fertilize or outcross. Typically, angiosperms have hermaphrodite flowers and stamens and ovaries are placed within the same flowers. Gymnosperms are mostly monoecious (male and female organs in separate flowers on the same individual) or dioecious (complete separation of male and female individuals). The sex habits of plants are however highly varied with three main features that may promote out-crossing:

• the spatial separation of male and female reproductive organs within and between plants
• the temporal separation of male and female reproductive activity within flowers
• the presence or absence of self-incompatibility

On the following pages, you find six examples of how sexual intercourse in plants works.