The importance of nitrogen (N): In legumes, atmospheric nitrogen is symbiotically fixed to ammonia in root nodules and transported as ammonium ion.
Integrates the chlorophyll molecule, acts in photosynthesis. It acts in the synthesis and is an integral part of proteins, in the setting of flowers, increases the number and retention of pods. It directly increases productivity, increases the weight (density) of grains. Increases the oil content of the beans.
Nitrogen (N) deficiency appears in the leaves, changing from dark green to pale green with slight yellowing, progressing until all the leaves turn yellow. This symptom appears first on the lower leaves but also spreads to the upper leaves. The symptom appears last on young leaves because N is an extremely mobile element in the plant, being translocated from old tissues to new leaves. Plant growth is slow, with smaller plants and low yields and causes low levels of protein in the grains.