Natural Product 2‑Amino-3-methylhexanoic Acid Stimulates Cucumber Growth via Nutrient and Energy Coordination

Plant growth regulators (PGRs) play a critical role in
modulating
plant development and stress responses. This study investigates the
mechanism by which 2-amino-3-methylhexanoic acid (AMHA), a novel natural
small-molecule PGR, stimulates cucumber growth. Results show that
AMHA increased trehalose-6-phosphate and indole-3-acetic acid levels,
promoting root development. The improved root architecture enhanced
the uptake and utilization efficiency of key nutrients, including
N, P, K, and Fe. In shoots, AMHA upregulated photosynthetic genes
(CHL27, MgCh, LHCB3, LHCB4, and PsbY), leading to
an increased stomatal conductance and net photosynthetic rate. Additionally,
elevated sucrose production in source leaves, coupled with its SWEET-transporter-mediated
allocation to sink tissues, further fueled growth. By integrating
these pathways, AMHA targets core physiological and molecular processes,
demonstrating strong potential to improve crop productivity. These
findings establish AMHA as a promising PGR that coordinates phytohormone
signaling, nutrient uptake, and sucrose metabolism to enhance plant
vigor, offering valuable insights for modern, eco-friendly agricultural
practices.