Citation
On growth-accelerating substances in the coleoptile of Avena sativa
TL;DR
A diffusible substance (later named auxin) causes cell elongation
Went's discovery of auxin - the plant hormone responsible for phototropic bending - solved the mystery Darwin had identified 46 years earlier. By demonstrating that a diffusible chemical substance moves asymmetrically in response to light and causes differential cell elongation, Went provided the mechanistic basis for directional growth.
This discovery transformed our understanding of how organisms translate environmental signals into growth responses, establishing the foundation for understanding resource-seeking behavior at the molecular level.
Key Findings from Went (1926)
- A diffusible substance (later named auxin) causes cell elongation
- Auxin redistributes asymmetrically in response to light
- Higher auxin concentration on shaded side causes faster elongation
- This differential growth creates bending toward light