poster
Combined transcriptomics and proteomics profiling reveals mechanisms underlying nitrogen use efficiency in popcorn (Zea mays var. everta)
Nitrogen (N) is essential for agriculture and its excessive use causes severe environmental damage. Improving nitrogen use efficiency (NUE) is crucial for achieving more productive crops under conditions of limited N availability. To the best of our knowledge, this is the first study aiming to integrate the morphophysiological responses, transcriptomics and proteomic profiles of leaves and roots of popcorn to understand NUE. For this, two NUE-contrasting inbred lines P2 (high NUE) L80 (low NUE), were cultivated under high (100% of N supply) and low (10% of N supply) N conditions. Morphological and physiological traits such as photochemical quenching (qP), non-photochemical quenching (NPQ), quantum yield of photosystem II (ΦPSII), and potential photosynthesis (Apot) were evaluated. P2 showed more pronounced vegetative growth under low N, as well as higher values of qP, NPQ, ΦPSII and Apot. Comparative transcriptomics and proteomics analysis revealed that more than 215 differentially accumulated proteins (DAPs) and 430 differentially expressed genes (DEGs) were involved in the response to low N in both lines. In leaves, DAPs and DEGs involved in the response to oxidative stress, energy metabolism, and photosynthesis represented the main differences between P2 and L80. In roots, the mechanisms of nitrate transport, ammonium assimilation, and amino acid metabolism seem to have contributed to the improved NUE in P2. This study provides valuable insights into the molecular mechanisms underlying NUE and opens avenues for molecular breeding aimed at selecting superior genotypes for the development of a more sustainable agriculture.