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, NO₃⁻ 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