Oldest leaves most chlorotic . . . . . Chlorosis definitely interveinal, so that at least the main veins remain green. Plants are not usually spindly . . . . . Chlorosis is the first visible symptom. Leaf edges curl upward in severe defficiencies . . . . .
Necrosis appears as sunken necrotic spots which appear shiny from the back of the leaf.
These spots have no particular location with respect to veins. Bright yellow and orange colors of the chlorotic leaves are common . . . . . Necrosis occurs as gradual drying of interveinal areas followed by drying of the remaining tissues. Bright coloration is not common in chlorotic leaves . . . . . Chlorosis is not the first visible symptom.