Auxins are the plant growth hormones that control the growing parts of the plant, stimulate cell elongation, differentiation of xylem and phloem, fruit development, apical dominance etc.
Auxins influence gibberellins that promote cell elongation and thus increases plant length. They increase the distance between nodes thus spacing the branch points. Auxins control seedling orientation and always move away from light and downward due to gravity. In areas, where auxin is highly concentrated, cell growth is more. Auxin when applied, also stimulate root branching by initiating roots at the cut stem.
