Effect of l‐amino acid‐based biostimulants on nitrogen use efficiency (NUE) in lettuce plants

BACKGROUND: Biostimulants are increasingly integrated into production systems with the goal of modifying physiological processes in plants to optimize productivity. Specifically, l‐α‐amino acid‐based biostimulants enhance plant productivity through improved photosynthesis and increased assimilation of essential nutrients such as nitrogen (N). This element is a major component of fertilizers, which usually are applied in excess. Thus, the inefficient use of N fertilizers has generated a serious environmental pollution issue. The use of biostimulants has the potential to address problems related to N fertilization. Therefore, the objective of this study is to analyze whether two biostimulants based on l‐α‐amino acid (Terra Sorb® radicular and Terramin® Pro) designed by Bioiberica, S.A.U company can compensate deficient N fertilization and test its effect on lettuce plants. Growth, photosynthetic, N accumulation, and N use efficiency (NUE) parameters were analyzed on lettuce leaves. RESULTS: Results showed that regardless of N fertilization, the use of both biostimulants, especially Terramin® Pro, increased biomass production. Moreover, both biostimulants enhanced photosynthetic, NO(3) (−) and total N accumulations as well as NUE parameters. CONCLUSION: Therefore, Terra Sorb® radicular and Terramin® Pro constitute a useful tool for crops development in N‐limiting areas, and in intensive agricultural areas without N deficiency allowing the reduction of N inputs without impairing crop yields and reducing environmental impact. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.