Role of Zinc in Nitrogen Fixation

• Context (DTE): Research reveals zinc has a crucial role in making legumes resilient to climate change.

Leguminous plants

• Leguminous plants, also known as legumes, are a family of plants (Fabaceae).
• It includes various species such as beans, peas, lentils, chickpeas, and peanuts.
• Legumes have a wide range of uses, including as food crops, forage for animals, green manure, and in the production of biofuels.
• Legume crops can form symbiotic relationships with rhizobia, a bacteria that fixes atmospheric nitrogen in root nodules. This helps them capture nitrogen from the air and convert it into a form the plants can use. This process is called nitrogen fixation.

Nitrogen Fixation

• It is a biological process in which nitrogen gas (N2) is converted into ammonia (NH3) or other nitrogen-containing compounds.
• It is essential for life on Earth, as most organisms, including plants and animals, require nitrogen in the form of amino acids and nucleotides to build proteins and nucleic acids.

To know more, refer > Symbiotic Nitrogen fixation

Zinc and Nitrogen Fixation

• Zinc is an essential micronutrient for plants. It helps in growth and development, photosynthesis, protein synthesis and transcription, etc.
• Researchers have discovered that zinc plays a crucial role in the nitrogen fixation process of legumes.
• Legumes use zinc as a secondary signal to integrate environmental factors and regulate nitrogen fixation efficiency. The mechanism works due to a transcriptional regulator called Fixation Under Nitrate (FUN).
• FUN is inactivated by zinc through the formation of large filament structures, which are dismantled to release active FUN when zinc levels are low.
• The fixation of nitrogen increases nitrogen availability, both for legumes and for crops that rely on nitrogen left in the soil after legumes are grown.
• It ensures a more stable crop yield, reduces the need for artificial fertilisers and enables the cultivation of legumes in new, previously unsuitable areas.