to study the effects of applied nitrogen levels and wild mustard densities on the growth of wheat and wild mustard, a field experiment was conducted at re-search and experimental field of islamic azad university of ahvaz-iran. the effects of three nitrogen levels namely 90, 150 and 210 kg.ha-1 and four wild mustard densities such as 0, 5, 10 and 15 plants.m-2 were evaluated in split plot arrang...

crop rotation is one of the essential practices in sustainable agricultural systems, be-cause of its effects on soil fertility and other benefits including a reduction in weed compe-tition. a field experiment was conducted at chaparsar rice research station, tonekabon, iran, from 2002 to 2003 to assess the influence of crop rotation, time of planting, and till-age depth on rice (oryza sativa l....

abstract use of empirical competition models is one of approaches in integrated weed management strategies. in order to investigation of this approach in simulation of yield loss of bean (phaseolus vulgari. l.) caused by jimson weed (datura stramonium l.) interference, an experiment was conducted in national bean research station, in khomein, in 2007. the experiment design was randomized comple...

Experiments comparing conventional and organic systems often report similar yields despite substantially higher weed abundance in the organic systems. A potential explanation for this observation is that weed– crop competition relationships differ between the two types of systems. We analysed weed and crop yield data from the Rodale Institute Farming Systems Trial (FST), which provides a unique...

Many studies of plant competition have been directed towards understanding how plants respond to density in monocultures and how the presence of weeds affects yield in crops. In this Botanical Briefing, the development and current understanding of plant competition is reviewed, with particular emphasis being placed on the theory of plant competition and the development and application of mathem...

abstract in order to evaluate the influence of nitrogen application and duration of weed interference on corn (zea mays l.) yield and yield components, a field study was conducted in 2004 at the ferdowsi university of mashhad research field. the experimental design was a randomized complete block with a factorial treatment arrangement replicated three times. nitrogen fertilizer was applied at r...