Light and dark assimilation of nitrate in plants

Abrol, Y. P. ; Sawhney, S. K. ; Naik, M. S. (1983) Light and dark assimilation of nitrate in plants Plant, Cell & Environment, 6 (8). pp. 595-599. ISSN 0140-7791

Full text not available from this repository.

Official URL:

Related URL:


Heterotrophic assimilation of nitrate in roots and leaves in darkness is closely linked with the oxidative pentose phosphate pathway. The supply of glucose-6-phosphate to roots and chloroplasts in leaves in darkness is essential for assimilation of nitrite into amino acids. When green leaves are exposed to light, the key enzyme, glucoses-phosphate dehydrogenase, is inhibited by reduction with thioredoxin. Hence the dark nitrate assimilatory pathway is inhibited under photoautotrophic conditions and replaced by regulatory reactions functioning in light. On account of direct photo-synthetic reduction of nitrite in chloroplasts and availability of excess NADH for nitrate reduclase, the rate of nitrate assimilation is extremely rapid in light. Under dark anaerobic conditions also nitrate is equally rapidly reduced to nitrite on account of abolition of competition for NADH between nitrate reductase and mitochondrial oxidation.

Item Type:Article
Source:Copyright of this article belongs to John Wiley and Sons, Inc.
Keywords:Higher Plants; Nitrate Assimilation; Light and Dark Regulation; Pentose Phosphate Pathway; Dark Respiration
ID Code:28893
Deposited On:18 Dec 2010 05:50
Last Modified:11 May 2011 06:15

Repository Staff Only: item control page