Absorption and accumulation of nitrate in plants: influence of environmental factors.

Plants adopt various strategies to fulfill their nitrogen nutrition requirement, the most important being the uptake of nitrate from the soil and its subsequent assimilation in to amino acids. The uptake of nitrate is energy dependent and is an active process involving high affinity and low affinity transport systems. The net uptake of the anion depends upon both influx as well as on its passive efflux. When the uptake far exceeds over its assimilation in the plant, there is considerable accumulation of nitrate in the plant parts making them unfit for human and cattle consumption. Various environmental factors affect the uptake and accumulation of nitrate, which along with the genetic component of the plant affecting the net uptake and accumulation of the nitrate, need to be considered and carefully manipulated for effective nitrogen management in the plant, soil and aquatic environment.