Transfer of pollen grains from anther to stigma of another flower of same plant is known as 

Geitonogamy refers to the transfer of pollen grains from the anther of a fl ower to the stigma of another fl ower within the same plant. It involves the cross-pollination of flowers on the same individual plant. In
geitonogamy, the pollen is transferred between different flowers but within the same plant, which can occur through various means, such as wind, insects, or self-pollination.

(2) Xenogamy, on the other hand, refers to the transfer of pollen from the anther of one plant to the stigma of another plant, resulting in cross-pollination between two different plants. 

(3) Autogamy refers to self-pollination, where the transfer of pollen occurs from the anther to the stigma within the same fl ower or between flowers of the same individual plant.

(4) Cleistogamy is a unique reproductive strategy where the flowers remain closed, and self-pollination occurs
within the closed fl ower without any external pollinators or pollen transfer.