Ecophysiological responses of two poplar species to intraspecific and interspecific competition under different nitrogen levels

AimsPopulus deltoidesandP. euramericanaare widely used in China as major forestry species. At present, little is known about their responses to nitrogen (N) deficiency when grown in monocultures or mixed plantations. The aim of this investigation was to analyze the growth, and morphological and physiological responses ofP. deltoidesandP. euramericanato different N levels under competition conditions.