|Stadler, J; Gebauer, G: Nitrate reduction and nitrate content in ash trees (Fraxinus excelsior L.): Distribution between compartments, site comparison and seasonal variation, Trees, 6, 236-240 (1992), doi:10.1007/BF00224342|
Nitrate reductase activity (NRA), nitrate content and biomass components of leaflets, leaf stalks, old stem, current-year stem and roots of ash trees (Fraxinus excelsior L.) growing in their natural habitats were investigated. In addition, NRA, total nitrogen and nitrate concentration were analyzed in the leaves and roots of ash trees from four different field sites. The highest NRA per gram biomass and also per total compartment biomass was found in the leaflets, even though root biomass was much higher than total leaflet biomass. The highest nitrate concentrations were found in the leaf stalks. Correlations between nitrate availability in the soil and NRA in leaves were not significant due to high variability of the actual soil nitrate concentrations. The seasonal variation in foliar NRA, nitrate concentration and total nitrogen concentration is much smaller in F. excelsior than reported for herbaceous species and is mainly caused by changes in the actual soil nitrate availability and by senescence of the leaves.
Insect interactions with natural and man-made toxins
Führung | Grüne Apotheke: Heilpflanzen
Führung | Faltergarten: Schmetterlinge und ihre Raupenfutterpflanzen
Kurzführung | Botanische Mittagspause
Führung | Gin: Diese Pflanzen stecken drin