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Question
List the different types of pollination depending upon the source of pollen gain.
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Solution
Pollination is the process of transfer of pollen grains from anther to stigma.
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Depending on the source of pollen grains, pollination can be divided as follows:
- Autogamy - It is the transfer of pollen grains from anther to stigma of the same flower. Autogamy requires the anther and the stigma to lie close. It also requires synchrony in the pollen release and stigma receptivity. Plants like Viola and Oxalis produce two kinds of flowers: chasmogamous flowers (with exposed anther and stigma) and cleistogamous flowers (plants that do not open at all and in which only autogamy occurs).
- Geitonogamy - It is the transfer of pollen grains from the anther of one flower to the stigma of another flower in the same plant. Genetically, it is similar to autogamy, but it requires pollinating agents.
- Xenogamy - It is the transfer of pollen grains from the anther to the stigma of a different plant. Pollination causes genetically different pollen types to be brought to a plant.
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