Question

What is the difference between autogamy and geitonogamy?

Answer 1

Autogamy vs Geitonogamy
Autogamy is defined as a type of self pollination that is mainly observed in flowering plants, where the pollen grains of an anther of a flower are deposited on the stigma of the same flower.	Geitonogamy is defined as a type of pollination (self) in which the pollen grains of the anther of a flower get matured and deposited on the stigma of another flower of the same plant.
Pollination Type
Autogamy is a type of self-pollination.	Regards to the function, geitonogamy is a type of cross-pollination, but in the context of genetics, it is a type of self pollination.
Adaptations
In autogamy, plants are adapted to deposit pollen grains of the anther on the stigma of the same flower. This type of pollination is favoured before opening the flower.	Presence of multiple flowers on a single stem is a factor for geitonogamy.
Stigma Belongs to
Pollen grains are deposited on the stigma of the same flower in autogamy.	Pollen grains are deposited on the stigma of another flower that of the same plant in geitonogamy.
Advantages
No external pollinating agents are necessary for pollination in autogamy.	Maintenance of parental characteristics indefinitely is an advantage of geitonogamy.
Disadvantages
No genetic variation is produced by autogamy.	Energy wastage on pollinator attractants is one disadvantage of geitonogamy.
Examples
Tridax, orchids, sunflowers are pollinated by autogamy.	Plants with multiple flowers on a single stem are examples for geitonogamy.