Discovering molecular mechanisms regulating nitrogen demand signalling and nitrogen use efficiency in plants

Nitrogen (N) is a key determinant of crop productivity. In agriculture, the demand for nitrogen (N) fertilisers to produce food, fibre, and feed from crops and pastures is increasing dramatically. The adverse environmental effects of using N-fertilisers in their current form, however, make their use unsustainable. A major challenge in agriculture is to reduce our reliance on environmentally devastating and expensive N-fertilisers. Breeds that boost nutrient-capture and have efficient N usage are highly-desired. Plants coordinate the distribution and allocation of nutrients from the source to support growth. How this is achieved remains unanswered. We have shown that plant-specific small secreted peptides and their receptors act between the roots and the shoots to coordinate root deployment, N-uptake, and, in legumes, nodule formation and N-fixation. This project aims to decipher the output of peptide hormone systems that control nitrogen demand signalling, N-uptake and -utilisation. It will identify key components of these peptide/receptor circuits and investigate how these peptide/receptor circuits operate and how they coordinate growth, maintain homeostasis and respond to nutritional cues. This project will help to identify and nominate key gene candidates for breeding programs for improving plant’s N economy, biological N-fixation and yield, all of which will ultimately aid for sustainable agriculture where N eco-efficiency of intensification of farming and grazing is highly-desired.