Early workers believed that inorganic salts were passively carried into the plant through diffusion with the absorption of water and further assumed that the translocation of the absorbed salts to different parts of the plant was dependent on transpiration. It is known that certain ions may attain a higher concentration in the cell sap of plant tissues than in the [...]
Until recently, the reductive amination of 2-oxoglutarate catalyzed by the enzyme glutamate dehydrogenase has been considered as the main reaction of ammonia assimilation in plants. Now there is convincing evidence that most of the inorganic nitrogen available to a plant is incorporated into the amide amino group of glutamine via the enzyme glutamine synthetase (L-glutamate ammonia ligase— ADP, GS). Subsequently [...]
Earth's atmosphere is nearly 80% nitrogen (N) but then the element is not sufficiently available to the organisms. It is known that some of the organisms have the capacity to assimilate molecular nitrogen and convert it into assumable form (Fig. 11-1). In general, four main types of organisms are recognized which can assimilate molecular nitrogen. These are symbiotic microorganisms inhabiting [...]