Pollination and Its Types - Practice Questions & MCQ

• It can be defined as the process of transfer of pollen grains from the anther of either the same flower or genetically similar flower.
• It is of two types:
  • Autogamy
  • Geitonogamy 

Autogamy:

• In this type of self-pollination, the transfer of pollen grains from the anther to the stigma takes place within the same flower.
• It is possible when both the anther and stigma are closely placed or there is a synchronization between pollen release and stigma receptivity.
• It occurs in the following three methods:
  • Homogamy or Chasmogamy: Chasmogamous flowers are open flowers and they perform autogamy when brought close together by means of folding or bending, for example, potato, sunflower, etc.
  • Cleistogamy: In some plants, flowers never open up, these are called cleistogamous flowers. The anthers dehisce inside these closed flowers to ensure pollination. Thus, cleistogamous flowers are invariably autogamous as there is no chance of cross-pollination. These flowers produce assured seed sets even in the absence of pollinators, e.g., Oxalis, Viola, etc.
  • Bud Pollination: The pollination taking place when the flower is in the bud condition is called as the bud pollination. It usually occurs in the flowers in which the stigma and the pollen grains mature or ripens even before the opening of the bud. Example Pea, Grass etc.

Geitonogamy:

• It is a kind of pollination where the pollen grains from the anther of a flower are transferred to the stigma of another flower borne on the same plant but at different branches. 
• It usually occurs in plants, which show monoecious condition, e.g., Cucurbita.

Cross-Pollination:

• It is also called the xenogamy.
• It involves the transfer of pollen grains from the flower of one plant to the stigma of the flower of another plant. 
• This is the only type of pollination which brings genetically different types of pollen grains to the stigma during pollination, e.g., papaya, maize, etc.