Interference between maize and Xanthium strumarium or Datura stramonium

Abstract

Xanthium strumarium and Datura stramonium are two of the most important weeds of maize in Iran. Their growth was compared in a field study conducted over 2 years. Relationships were derived between weed density and crop yield, yield components and various growth parameters. Yield, grain number ear-1 and grain weight were affected more by X. strumarium than by D. stramonium. Xanthium strumarium followed a pattern of growth resembling that of the maize, whereas D. stramonium continued growing for a longer period, mainly affecting maize during the grain-filling period. A large portion of the loss in maize yield caused by X. strumarium could be explained by a reduction in grain number ear-1, whe..