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About Water Hyacinth

Water hyacinth (Eichhornia crassipes) is an enthralling aquatic plant that is recognised for its quick growth and lovely appearance. It is endemic to South America (Brazil) and belongs to the Pontederiaceae family. It is also known as Common Water Hyacinth, Terror of Bengal, Beautiful Blue Devil.

Water Hyacinth – A Noxious Weed

Water hyacinth (Eichhornia crassipes) transform from an ornamental aquatic plant to a weed due to its aggressive growth and invasive characteristics. Several factors contribute to this transition:

• Rapid Reproduction: The fast vegetative reproduction of water hyacinth is well known. Each plant can produce a large number of daughter plants via stolons (horizontal stems), resulting in dense colonies in a short period of time. Because of its rapid reproduction rate, it can outcompete natural aquatic plants.
• Lack of Natural Predators: Water hyacinth may lack natural predators that assist restrict its population in locations other than its native habitat. In the absence of these natural checks, it can expand uncontrollably and cause infestation.
• Tolerance to Different Environments: Water hyacinth is extremely adaptable to a wide range of aquatic habitats, from slow-moving rivers to stagnant ponds and lakes. It can live in both freshwater and brackish water, making it well-suited for colonisation of a wide range of aquatic bodies.
• Nutrient Absorption: Water hyacinth is extremely efficient at taking nutrients from water, notably nitrogen and phosphorus. These nutrients work as fertilisers, promoting growth and giving it a competitive advantage over native aquatic plants that may struggle with nutrient availability.
• Resistance to Herbicides: Some water hyacinth strains have evolved resistance to pesticides typically used to limit their growth. This opposition makes effective management tactics difficult.
• Human Activities: Water hyacinth spread can be aided by human activity, such as the unintentional or intentional discharge of the plant into new habitats. Unwanted ornamental water hyacinth disposal into natural water bodies might result in unforeseen infestations.

Introduction of Water Hyacinth

• In 1884, Introduced to United States of America:
• In 18th to 19th Century: The Eichhornia may have been introduced into Egypt during the reign of Muhammad Ali of Egypt.
• Around the end of the 18th century, Warren Hastings is said to have imported this South American aquatic species to the Indian subcontinent as a present for his wife.
• It was first introduced to Sri Lanka in 1905.
• In 1884, the Eichhornia was introduced into Japan.
• In 1930, Eichhornia was introduced into China  as a feed, aesthetic plant, and sewage-control.
• In 1990, Eichhornia, which was introduced in Iraq.

A Love Story Leading to the Terror of Bengal

In the 18th century, a love story unfolded during a sea voyage to India, where Warren Hastings, a future Governor of Bengal, fell in love with Marian Imhoff, a young and attractive woman. Their relationship flourished, leading to Marian leaving her first husband, Karl Imhoff, and marrying Hastings after a divorce. As a gift, Hastings introduced the Eichhornia, a beautiful purple flowering aquatic plant from South America, to India. Unaware of its invasive nature, the Eichhornia rapidly spread and became known as the “Bengal Terror,” posing ecological hazards by choking water bodies across the nation. The legend attributes the introduction of this invasive species to the love affair, highlighting the unforeseen consequences that can arise from seemingly innocent actions.

Biological Control of Water hyacinth

Water hyacinth (Eichhornia crassipes) biological control entails using natural enemies or organisms to manage and suppress the growth and spread of this invasive plant. The goal is to achieve a balance between the Eichhornia population and its natural predators or pathogens, so lessening the detrimental influence on the ecosystem and local species.

Biological control of water hyacinth using insects

Neochetina bruchi popular name chevroned waterhyacinth weevil.

Neochetina eichhorniae, often known as mottled waterhyacinth weevil.

Belludura densa, also called Pickerelweed borer moth.

Sameodes albiguttalis

Acigona infusella an agent for biological control of waterhyacinth in Australia.

Orthogalumna terebrantis: Mite

Eccritotarsus catarinensis: Plant bug species from Santa Catarina, Brazil. It is a sap-feeding mirid that depletes the chlorophyll content of Eichhornia crassipes.

Biological control of water hyacinth using pathogen

Cercospora piaropi, Acremonium zonatum, Alternaria eichhorniae, Myrothecium roridum, Rhizoctonia solani and Uredo eichhorniae.

Conclusion

(Eichhornia crassipes) converts from a beautiful plant to an invasive threat due to its rapid growth and lack of natural predators. Introduced in India during the 18th century as a present from Warren Hastings to his love, Marian Imhoff, it quickly spread and became known as the “Bengal Terror.” Biological approaches, such as weevils and viruses, are being used to restrict its proliferation. The unforeseen consequences of introducing serve as a cautionary tale concerning invasive species. It continues to clog water bodies, endangering ecosystems. Vigilance and sustainable techniques are essential for mitigating its influence and keeping the balance of our environment.

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Codex Alimentarius

Good Laboratory Practices and Good Manufacturing Practices

Sources: USDA, FAO, CPS Journal, Cambridge, UF, UOC