Can the 15N dilution technique be used to study N2 fixation in tropical tree symbioses as affected by water deficit?

acetileno acetylene arbre forestier casuarina equisetifolia drought stress faidherbia albida forest trees frankia leucaena leucocephala measurement mesure methode methods multipurpose trees plant water relations plantule reduction relaciones planta agua relation plante eau rhizobium seedlings simbiosis symbiose symbiosis techniques water stress