Gibberellins are plant hormones that play a key role in shoot elongation by stimulating cell division and cell elongation in the stem.
Here’s how gibberellins help shoots grow:
- Cell elongation:
- Gibberellins cause the cells in the stem to stretch and lengthen, making the plant taller.
- They loosen the cell walls, allowing them to expand when water enters.
- Cell division:
- They promote rapid cell division in the growing regions (meristems) of shoots and young leaves.
- Internode elongation:
- Gibberellins especially affect the internodes (the spaces between leaves on a stem), making them longer.
- This gives plants a more elongated appearance, especially in grasses and cereals.
- Breaking dwarfism:
- In genetically dwarf plants, applying gibberellins can restore normal stem height by activating growth processes.
- Enhanced nutrient transport:
- As shoots elongate, gibberellins improve the movement of nutrients and water, supporting faster growth.
In simple terms, gibberellins make plants grow taller by helping stem cells divide and stretch, leading to increased shoot length and overall plant height.