Key Hypotheses

The science components of the project provide the basis to address 8 specific hypotheses:

1. Traits identified for improved plant nitrogen use efficiency (NUE) are coupled to other characteristics including rooting characteristics, drought resistance and biochemical indicators (Component 1).

2. The ability of rice plants to directly take up and utilise urea, and microbial N-fixation by exo/endophytes, could contribute significantly to the overall nitrogen (N) budget of the plant, and therefore NUE (Component 1).
    
3. Novel plant mechanisms (e.g. better plant urea uptake or overexpression of alanine aminotransferase) support use of enzyme inhibitors and other ways to reduce N emissions (Component 1, 2).
    
4. Agronomic ways to limit ammonia (NH₃), dinitrogen gas (N₂) and nitrate (NO₃^-) loss will raise crop NUE while reducing N₂O loss (Component 2).
    
5. Combining options to improve plant and agronomic NUE will give and additive gains in NUE (Component 2, 3).
    
6. Strategies for NUE improvement can be identified that provide win-win-wins for improved food, energy and environment (air, land, water, and climate) (Component 2, 3, 4).
    
7. Better recycling of organic N sources must address the economic and social barriers (Component 4).
    
8. Better characterization of national N losses and the economic benefits of improving NUE to the Indian economy will be critical in stimulating transformative change (Component 4).