How is nitrate assimilated by plants ?
In plants, absorption of nitrogen occurs in the form of nitrate (NO3−) and ammonia (NH3). For this, plants have both nitrate transporters and ammonia transporters. Generally, nitrogen moves inside the plant body in the forms of nitrate, dissolved ammonia and amino acids. Ammonia is changed into amino acids using the glutamine synthetase-glutamate synthetase pathway.
In case of nitrates, it is first reduced to nitrite (NO 2 - ) in the cytosol by nitrate reductase. Nitrite is then reduced to ammonia in the chloroplasts by nitrite reductase.