l‐2‐Aminopimelic acid acts as an auxin mimic to induce lateral root formation across diverse plant species

The identification of chemicals that modulate plant development and adaptive responses to stresses has attracted increasing attention for agricultural applications. Recent basic studies have identified functional amino acids that are essential for plant organogenesis, indicating that amino acids can regulate plant growth. In this study, we newly identified 2‐aminopimelic acid (2APA), a nonproteinogenic amino acid, as a novel bioactive compound involved in root morphogenesis. This biological effect was confirmed in several plant species. Our phenotypic analysis revealed that the bioactive 2APA is an l‐form stereoisomer. Overall, our study identified a promising root growth regulator and provided insight into the intricate metabolism related to root morphology. Here, we identified l‐2‐aminopimelic acid as a novel functional amino acid that promotes high lateral root density. By adding this amino acid, the root system in a wide range of dicotyledonous plant species was converted from a primary‐lateral root system to a fibrous root‐like system.