A member from Spain sent the following question to Ask the Expert:
"Hi
I want to know the (physiological ) reason why leaves of plant twisted I treated them 10 days with spray of indole acetic acid. "
Unfortunately I'm unable to post the photo he pasted to the message but it showed a pot of seedliungs in a laboratory with deformed leaves.
David Bracey answered:
" "Indole acetic acid (IAA) is a naturally occuring plant hormone or plant auxin. The term phytohormone has recently been given to similar compounds. IAA is produced in the growing tip of the plant and is involved in cell division and cell elongtion. F.W. Went first confirmed these growth effects in his classical experiments in 1926. His research led him to confirm that " plant hormones" were produced in the coleoptile or growing tip of Avena fatua, wild oat. These compounds caused the plant to twist and curl eventually led to death. As a direct result of this work some of the world's most successful and effective herbicides were discovered. The phenoxy accetic acids have proved very effective in controlling broadleaved weeds in grass crops such as wheat and barley."
