Basisdocument Nitraat

Dit rapport is de engelse versie van rapport 75843007. Bij dit rapport hoort een bijlage, getiteld: Appendix to report no. 758473012<br>Dit rapport bevat een systematisch overzicht en een kritische evaluatie van de belangrijkste gegevens over de prioritaire stof nitraat ten behoeve van het milieubeleid.DGM/SR /Cornet J

Integrated Criteria Document Nitrate

Separaat verschenen bijlage: Appendix Integrated Criteria Document Nitrate, Effects. Met rapportnummer 758473007. Onder nummer 758473012 is de engelse versie van dit rapport verschenen.<br>Dit rapport bevat een systematisch overzicht en een kritische evaluatie van de belangrijkste gegevens over de prioritaire stof nitraat ten behoeve van het milieubeleid.DGMH/SRCornet JP

Signaling interactions during nodule development

Nitrogen fixing bacteria, collectively referred to as rhizobia, are able to trigger the organogenesis of a new organ on legumes, the nodule. The morphogenetic trigger is a Rhizobium-produced lipochitin-oligosaccharide called the Nod factor, which is necessary, and in some legumes sufficient, for triggering nodule development in the absence of the bacterium. Because plant development is substantially influenced by plant hormones, it has been hypothesized that plant hormones (mainly the classical hormones abscisic acid, auxin, cytokinins, ethylene and gibberellic acid) regulate nodule development. in recent years, evidence has shown that Nod factors might act in legumes by changing the internal plant hormone balance, thereby orchestrating the nodule developmental program. In addition, many nonclassical hormonal signals have been found to play a role in nodule development, some of them similar to signals involved in animal development. These compounds include peptide hormones, nitric oxide, reactive oxygen species, jasmonic acid, salicylic acid, uridine, flavonoids and Nod factors themselves. Environmental factors, in particular nitrate, also influence nodule development by affecting the plant hormone status. This review summarizes recent findings on the involvement of classical and nonclassical signals during nodule development with the aim of illustrating the multiple interactions existing between these compounds that have made this area so complicated to analyze