Question

World’s most problematic weed is
A. Azolla
B. Wolffia
C. Eichhornia
D. Trapa

Answer 1

Hint: Weed is an unwanted or undesirable plant that should be removed before growing plants. Weeds also grow in water. Sometimes aquatic weeds grow and cover the whole water body making it difficult for other aquatic plants to grow in the presence of them.

Complete answer: Weed is an unwanted or undesirable plant that should be removed before growing plants. Like land, water also has many types of aquatic weed that grow terribly. This feature is a killer for other aquatic plants. Water hyacinth is the world’s most problematic aquatic weed. Water hyacinth rate of growth is very high. They can cover whole water bodies in which they live, making them unable to grow in that water body. Eichhornia crassipes is a perennial plant that is also known as water hyacinth. Water hyacinth utilizes and consumes all the nutrients, solar energy, and land, this causes the deficiency of nutrients and land for other plants, and sometimes they possess a threat to aquatic animals as well. Eichhornia is the world’s most problematic aquatic species.
Hence, the correct option is (C).

Additional Information:
Azolla is a fern also known as duckweed fern. They have the capacity to fix the nitrogen and due to this ability of Azolla, it is used as a biofertilizer. Wolffia is a flowering plant, and it is the smallest of all the vascular plants on earth. Its common name is rootless duckweed. In some parts of the world, it is eaten as vegetables. The common name of tapa is singhara, water chestnut, and water caltrop.

Note: Water hyacinth is also known as the terror of Bengal, they grow in hot and humid conditions. In India, they mainly grow in Bengal. In Bengal, fishes are the main source of income but due to water hyacinth fishes pose a threat, so this is the reason behind calling water hyacinth terror of Bengal.