Symptoms of which nutrient deficiency appear first on the older leaves and then advance up the stem to younger leaves ?

-Nitrogen (N) deficiency causes pale, yellowish-green corn plants with spindly stalks.
-Because nitrogen is a mobile nutrient in the plant, symptoms begin on the older, lower leaves and progress up the plant if the deficiency persists.
-Symptoms appear on leaves as a v-shaped yellowing, starting at the tip and progressing down the midrib toward the leaf base.
-In acute deficiency, flowering is greatly reduced.
-Lower protein content.
-Plants mature early, crop quality and yield are often reduced.