Final diagnosis


Magnesium deficiency

Severe magnesium deficiency on potato leaf with browning and necrotic spots inside the leaflets
Magnesium deficiency imposed on potato leaf with lightening and then browning and necrosis within the leaflets
Incipient magnesium deficiency (with light interveinal chlorosis and no necrosis)
Potato leaf  having chlorosis due to a <b>magnesium deficiency</b> (right), leaf without symptoms (left).