Similarities and Differences Between IAA and IAA-K

Similarities and Differences Between Indole-3-acetic Acid (IAA) and Its Potassium Salt (IAA-K)​ Indole-3-acetic Acid (IAA) is the primary endogenous auxin in plants, while Indole-3-acetic Acid Potassium Salt (IAA-K) is its water-soluble derivative. Both play key roles in regulating plant growth, but they differ in 理化性质 (physicochemical properties), application flexibility, and stability. Below is a structured comparison of their similarities and differences.​ 1. Core Similarities​ 1.1 Biological Mechanism of Action​ Both IAA and IAA-K exert growth-regulating effects by binding to plant auxin receptors (e.g., TIR1/AFB proteins). This activates downstream signaling pathways that:​ Promote cell division and elongation in meristematic tissues (root tips, shoot apices, and young leaves).​ Regulate root development (induce lateral roots, enhance root hair density) and fruit set (reduce flower/fruit abscission).​ Modulate stress responses (stimulate proline synthesis to improve drought/sa…