What to Look For.
Sulfur deficiency from a distance can resemble plant nitrogen stress. Upon closer look nitrogen deficiency will show up as chlorosis beginning from the leaf tip and progressing down the mid rib. Sulfur deficiency also produces chlorosis, but the symptoms produce striping on the leaf.
The other differing factor is that nitrogen is mobile in the plant and sulfur is not, so deficiency symptoms will show up in the lower canopy for nitrogen while sulfur will show up in the newest leaves. It is important to be able to differentiate the two because adding more N to the yellow areas of the field will not help if the problem is actually sulfur. Either deficiency is not mutually exclusive so both symptoms may show up on the plant making a diagnosis challenging.