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प्रश्न
Explain water pollination in detail with its types.
उत्तर
Definition:
Pollination carried out by water is called hydrophily.
Two types of hydrophily:
i. Hypohydrophily:
- In this pollination occurs below the surface of the water.
- Here the pollen grains are heavier than water, thus they sink down and caught by stigmas of female flowers.
- For e.g. In Zostera (sea grass) the pollen grains are long, ribbon-like, and without exine.
ii. Epihydrophily:
- In this pollination occurs on the surface of the water.
- The pollen grains float on the water surface and reach the stigma of the female flower.
- Vallisneria is a submerged dioecious, fresh water aquatic plant. In this, female flowers reach the water surface temporarily to ensure pollination and male flowers float on the surface of the water.
- The specific gravity of these pollen grains is equal to that of water. Due to which they float on the surface of the water.
- Due to water currents, pollen grains are carried to stigma and pollination occurs.
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