Breakthrough Research Shows Reducing Nitric Oxide Levels Enhances Nitrogen Use Efficiency in Plants

Novel Approach Promises Sustainable Agriculture by Reducing Dependence on Nitrogen Fertilizers.

Researchers from the National Institute of Plant Genome Research (NIPGR) have demonstrated that reducing nitric oxide (NO) levels in plants can significantly enhance nitrogen uptake and Nitrogen Use Efficiency (NUE) in crops such as rice and Arabidopsis. This breakthrough offers a sustainable pathway to improving agricultural practices while addressing environmental concerns and reducing dependence on nitrogen fertilizers.

Existing methods to enhance NUE primarily rely on agronomic strategies such as:

• Split application of inorganic nitrogen fertilizers.
• Slow-release nitrogen fertilizers.

However, these practices have notable drawbacks. They are costly, emit excessive amounts of nitrogen oxides (NOx), contribute to greenhouse gas emissions, and rely on energy-intensive fertilizer manufacturing. These limitations have driven the search for more efficient and eco-friendly solutions to address global challenges related to food security and climate change.

Innovative Findings from NIPGR Study

The NIPGR team, led by Dr. Jagannath Swain, Dr. Jagadis Gupta Kapuganti, Dr. Nidhi Yadav, and Dr. Sanjib Bal Samant, has identified a novel mechanism to improve NUE by modulating NO levels in plants. By regulating NO levels, the researchers were able to enhance the activity of nitrate transporters, particularly high-affinity transporters (HATs) like NRT2.1 and NRT2.4, which play a crucial role in nitrogen uptake under low nitrogen conditions.

The study employed both genetic and pharmacological approaches:

1. Pharmacological Approach: Wild type (WT) plants were treated with NO donors (e.g., SNAP) and NO scavengers (e.g., cPTIO) to monitor their NUE.
2. Genetic Approach: Overexpression of phytoglobin, a natural NO scavenger, was shown to boost the expression of HATs, leading to enhanced nitrogen uptake and improved NUE.

Nitrosylation of proteins, mediated by NO, was identified as a key regulatory process influencing NUE.

Potential Applications and Future Directions

The innovative approach opens the door to a range of practical applications, including:

• NO Scavenging Formulations: Development of formulations for direct application in agroecosystems to improve NUE and reduce nitrogen fertilizer usage.
• Soil Microbial Solutions: The team is investigating soil bacteria capable of acting as NO scavengers, which could naturally enhance NUE in crops.

Dr. Kapuganti highlighted, “Our study provides a promising pathway for sustainable agricultural practices by introducing NO scavenging strategies that reduce the reliance on synthetic nitrogen fertilizers. These solutions can be tailored to diverse agroecosystems.”

Environmental and Economic Benefits

This innovative solution diverges from traditional fertilizer-dependent methods by offering:

• Reduced environmental impact from NOx emissions.
• Cost-effective alternatives to expensive nitrogen fertilizers.
• Sustainable agricultural practices that align with global efforts to mitigate climate change.

Support and Next Steps

The study was supported by the Agro-Nutritional Research Foundation (ANRF), established through the ANRF Act, 2023. The team is now focusing on developing bacteria-based NO scavenging systems and further refining genetic and pharmacological techniques to make these solutions widely accessible.

This research represents a significant leap forward in improving NUE, paving the way for sustainable agricultural practices that enhance crop yield while addressing global environmental challenges.