Required in the AIA (cell volume promoter) synthesis pathway. It acts as an inhibitor of ribonuclease activity (cell multiplication).
Deficiency – Begins with a whitish green coloration that develops in the tissue at the base of the leaf on either side of the midrib. The leaf blade has a prominent flare in the chlorosis zone. As the leaf becomes older, the chlorotic tissue acquires a rusty color.
The leaf margins, in the ferruginous area, are usually green. Younger, developing leaves have white chlorotic tissue that, as the deficiency progresses, turn rusty brown. The plant’s growth is stunted and the leaves, which are rusty in color, become prominent in later stages.
