Phosphate or nitrate imbalance induces stronger molecular responses than combined nutrient deprivation in roots and leaves of chickpea plants

The negative effects of phosphate (Pi) and/or nitrate (NO 3 − ) fertilizers on the environment have raised an urgent need to develop crop varieties with higher Pi and/or nitrogen use efficiencies for cultivation in low‐fertility soils. Achieving this goal depends upon research that focuses on the identification of genes involved in plant responses to Pi and/or NO 3 − starvation. Although plant responses to individual deficiency in either Pi (–Pi/+NO 3 − ) or NO 3 − (+Pi/–NO 3 − ) have been separately studied, our understanding of plant responses to combined Pi and NO 3 − deficiency (–Pi/–NO 3 − ) is still very limited. Using RNA‐sequencing approach, transcriptome changes in the roots and leaves of chickpea cultivated under –Pi/+NO 3 − , +Pi/–NO 3 − or –Pi/–NO 3 − conditions were investigated in a comparative manner. –Pi/–NO 3 − treatment displayed lesser effect on expression changes of genes related to Pi or NO 3 − transport, signalling networks, lipid remodelling, nitrogen and Pi scavenging/remobilization/recycling, carbon metabolism and hormone metabolism than –Pi/+NO 3 − or +Pi/–NO 3 − treatments. Therefore, the plant response to –Pi/–NO 3 − is not simply an additive result of plant responses to –Pi/+NO 3 − and +Pi/–NO 3 − treatments. Our results indicate that nutrient imbalance is a stronger stimulus for molecular reprogramming than an overall deficiency.