Occurrence of foliar nitrate reductase activity not induced by nitrate in symbiotic nitrogen-fed black alder (Alnus glutinosa) S. Benamar, G. Pizelle and G. ThiéryAnn. For. Sci., 46 Supplement (1989) 777s-781sDOI: https://doi.org/10.1051/forest:198905ART0173