Pollination in plants can occur differently. This is dependent on the type of plant. The habitat also determines it. There is a difference in the way terrestrial and water plants pollinate.
Water plants have a unique method of pollination. They are known to depend on water to carry their pollen.
Water-pollinated plants produce pollen that cannot dissolve in water. It either stays on the surface or sinks beneath. They do not have pollinator-attracting resources.
This is unlike the terrestrial plants that have nectar and beautiful flowers to attract pollinators. The stigma of water-pollinated plants also lasts longer, whether above or beneath the water.
Epihydrophily and hypohydrophily – What’s the difference?
Epihydrophily and hypohydrophily are the two main types of Hydrophily pollination. They are challenging to differentiate.
For both, hydrophily pollination happens through the water. Pollination involves water-pollinated processes. The difference is where pollination occurs.
Hydrophily is primarily common in rivers and streams. It happens when the water flows and distributes the pollen. It is prevalent in still and shallow waters.
This is for the plants that require water for pollination to occur. It is essential to differentiate how the two categories of plants pollinate.
- Hydrophilous pollination
- Epihydrophilly pollination
What is hypohydrophily pollination?
Hypohydrophily is a pollination type that happens in submerged plants. In rivers and streams, there are those plants that survive submerged below the water.
This is relatively uncommon, given that few plants fall under this category. A lot of information is only available for plants above the water surface.
For hypohydrophily, the distribution of pollen is also through the water. The plants access the pollen grains that are inside the water. It happens beneath the surface.
Experts believe that the pollen is heavier than the water in such a case. Pollination occurs when the stigma of the submerged plants catches the sinking pollen.
Example of a Hypohydrophily
Example 1: Seagrasses
Among the common examples of hypohydrophily include seagrasses. These are among the flowering plants that do very well in marine environments. They are common across the tropics to the Arctic circle marine regions.
This plant has long green, grass-like leaves. However, they are not categorized as true grasses. The seagrass produces tiny flowers and seeds. This is a plant whose female flower remains submerged in water.
Example 2: Najas
There Najas are also under this category. They are also referred to as the water-nymphs. It is a common aquatic plant throughout New England. These plants do well in shallow waters.
They are also common to terrestrial plants because of their flowers and roots. The flowers are an indication that they reproduce by pollination.
Example 3: Ceratophyllum
The Ceratophyllum has been featured as the most common example of hypohydrophily. The Ceratophyllum is primarily found in streams, ponds, and marshes. They survive well in tropical regions. They also do well in quiet waters.
Pollination happens when the plant breaks the male flowers for all these plants. The pollen breaks and settles on the water’s surface. It later sinks and comes into contact with the stigma.
What is Epihydrophilly pollination?
The other type of water-pollinated plant is epihydrophilly pollination. It is the pollination common with plants above the water surface. It is among the most common types of pollination for plants in water habitats.
Epihydrophilly pollination is actualized by the pollen floating on water surfaces. It is released when the male plant breaks on the surface. It releases insoluble pollen that does not sink. It is also identified as having sticky properties.
The wind is identified as very important in this type of pollination. It helps with the transportation of pollen across the water’s surface.
The pollen touches the stigmas of the female flowers. This type has to happen only for plants living above the surface.
Example of Epihydrophily
Example 1: Vallisneria
A good example is epihydrophily is Vallisneria pollination. The plant has a very long pedicel. It can easily reach the water’s surface. The wind carries the pollen passively on the water. It reaches the female flower and therefore pollinates.
Example 2: Hydrilla
The hydrilla is also among the few examples of epihydrophily pollination. The plant has a long female flower extending to the water’s surface. The flower waits and catches the pollen grains released on the surface.
Overall, water-pollinated plants are different from terrestrial plants. They have a unique way of pollination. Some plants are pollinated above the water’s surface. These are referred to as the hypohydrophily.
There is also the category of pollination beneath the water’s surface. These are commonly referred to as epihydrophilly. All these are plants pollinated by pollen carried through the water.
In hydrophily, the pollen is covered with a mucilaginous layer. This is known as the protecting agent from the water. The pollen cannot get wet. It reaches the stigma in the original state and pollinates the plant.