Effects of Exogenously Applied Indole-3-Acetic Acid (IAA) to Cotton

There is a need in the cotton industry for cultivars with enhanced lint yield potential and high-quality fiber properties. Indole-3-acetic acid (IAA) is a phytohormone that is predominantly responsible for cell elongation and required for primary elongation in cotton fiber development. An increase in IAA at specific fiber developmental stages may promote increased lint percent and longer fibers. Objectives of this research project were to determine how exogenous applications in a field environment affect fiber traits and lint yield potential in diverse genotypes. The first study examined application methods to ascertain the optimal placement and timing of IAA. The second study focused on genotype reactions to elevated levels of IAA. Results indicate exogenously applied IAA provided a potential yield increase but did not improve fiber length. Further research needs to be conducted to effectively understand IAA?s role in fiber development and establishing protocols for maximizing IAA potential in a field environment.