Reproduction in Hydrilla
Hydrilla can reproduce in both ways, sexually and asexually by vegetative means, contributing to its survival and spread.
Sexual Reproduction
Sexual reproduction in Hydrilla can lead to genetic variations that help the plant adapt to a broader range of environments. Hydrilla flowers are small, unnoticeable and often submerged. The pollination of H. verticillata is facilitated by epihydrophily.
- The pollen dispersal process of H. verticillata takes place only in sunlight. The male flowers lack a hypanthium, or “flower stalk,” instead reach the surface by detaching from the plant and floating up as a mature, air-filled bud.
- The male flowers are brought to the water surface by buoyancy from the attached gas bubble developed under the water.
- As the male flowers are exposed to sunlight, the sepals accumulate elastic force, causing the cracks in the top of the external bracts to expand and release the male flower.
- During this time interval, the male flowers do not release pollen until they reach the water surface.
- The female flower reaches the water surface by elongation of the hypanthium.
- The petals and sepals of the female flower form an inverted bell with an air bubble and the corolla opens and forms a funnel, which is hydrophobic, If the flower becomes submerged, the petals and sepals and close again enclosing an air bubble to protect the stigmas from water, ensuring air pollination
- Fertilisation occurs, and the female flowers develop into berry-like fruits containing seeds that can remain dormant in the sediment for long periods.
Vegetative Reproduction
Vegetative Reproduction occurs through stem fragmentation, axillary buds (turions), and tubers.
- Hydrilla is highly proficient in vegetative reproduction primarily through fragmentation, where fragmented pieces of stem that contain at least one node can sprout into a new plant, which can be dispersed by water movement, human activities, or the activities of animals.
- Tubers: Another method utilised by hydrilla is the formation of tubers, specialised underground storage structures that formed on the rhizomes and each one can produce 6,000 new tubers, allowing the plant to survive in adverse conditions and propagate rapidly. Tubers can remain dormant in the sediment and sprout under favourable conditions.
- Turion: Turions are formed in the leaf axils of the plant. They are broken off and once settled in the sediment they can sprout into a new plant. Axillary turions are on average half the size of tubers.
Unlike most plants, seed production in hydrilla is insignificant for reproduction. It appears that seed production is primarily used for long-distance dispersal. The monoecious form of hydrilla allocates more energy towards tuber and turion production compared to the dioecious form.
Hydrilla Plant
Hydrilla, also known as Water thyme or Indian star-vine, is commonly found in freshwater ecosystems such as lakes, rivers, and ponds. It is native to Asia but its rapid growth rate and high adaptations to various environmental changes make it the most invasive species worldwide. Over most of the United States and Florida, hydrilla has become the most problematic invasive aquatic weed and poses a threat to native vegetation. In this article, we will read about Hydrilla – characteristics, adaptations, and reproduction along with various adaptations of Hydrilla plant.
Table of Content
- What is Hydrilla Plant?
- Hydrilla Plant Classification
- Hydrilla Diagram
- Hydrilla Plant Characteristics
- Where is Hydrilla Found?
- Reproduction in Hydrilla
- What is Hydrilla Experiment?
- What are the Adaptations of Hydrilla verticillata?