Enhancing biological nitrogen use in crops: A translational research approach

 Manoj Prasad1*, Tirthankar Bandyopadhyay1, Rajeev Gupta2, Parveen Chhuneja3, Tina Barsby4, Alison Bentley4, Mariana Fazenda5, Ottoline Leyser5, Howard Griffiths5

1National Institute of Plant Genome Research, New Delhi, India

2International Crops Research Institute for the Semi-Arid Tropics, Telangana, India

3Punjab Agricultural University, Punjab, India

4National Institute of Agricultural Botany, United Kingdom

5University of Cambridge, United Kingdom

*Correspondence: [email protected]

 Abstract

Optimization of biological nitrogen (N) use by crops has assumed great significance in recent years due to ever increasing fertilizer costs and severe environmental pollution due to N leaching in the soil. This is particularly relevant for developing countries where farmers have limited resources and are confronted with the need to feed an ever increasing population amidst climate change. The present study is part of the Cambridge – India Network for Translational Research in Nitrogen (CINTRIN) which aims to translate our recent understanding of developmental N use in model plants such as Arabidopsis and Brachypodium to foxtail millet, wheat, sorghum and pearl millet by screening for nitrogen insensitive (NIS) ideotypes, analysing their relative N utilization, yield potential and subsequently establish candidate genes regulating N use in them. Among the all four studied crops, foxtail millet (Setaria italica L.) is a C4 model cereal that requires very low growth inputs, and is perfectly adapted to tropical semi-arid climate. The crop has one of the highest nutritional indices for human consumption, making it one of the most suitable crops for arid and semi-arid environments.  In the present study, we employ high-throughput phenomics platforms to examine agronomically important traits in 200 genetically and geographically diverse accessions of foxtail millet and use next generation comparative genomics and bioinformatic tools to identify candidate genes/QTLs regulating N use. We also propose to compare and analyse the variation in physiological N uptake/ use and allocation to grains by using high throughput 13N/15N partitioning experiments to identify parallels with nitrogen sensitive (NS) and nitrogen insensitive (NIS) genotypes. The overall objectives of the study are to couple molecular basis of plant development to the physiology of N uptake and partitioning thereby defining new NIS ideotypes and generate valuable information on cultivar-specific N fertiliser application and offering the same directly to farmers.