A field experiment was conducted for two consecutive years (2003 and 2004) to study the effect of row spacing (75, 65 and 55cm) and different weed competition durations (0, 15,30,45,60 days after emergence and throughout the growth period) on weeds density and biomass and growth and yield of maize. Reducing row spacing significantly suppressed the weed density and biomass. The maximum reduction...

crops that better tolerate weed competition or preempt resources from weeds may reduce dependence on herbicides and benefit an integrated weed management program. a field trail was conducted to determine the morphophysiological characteristics affecting tolerance and weed suppressive ability of some winter wheat cultivars in competition with rocket. the experimental treatments consisted of eigh...

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....

Management of nitrogen fertilization in crops is one of the most important components of integrated weed management. A two-year field experiment was conducted to determine the direct effects of wild mustard aboveground biomass and N content of wild mustard on oilseed rape yield. A set of factorial treatments was arranged in a randomized complete block design with four replications. Treatments w...

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...

in order to study of nitrogen absorb and use efficiency of wheat (triticum aestivum) and wild oat (avena fatua) at vegetative growth stage, a factorial experiment was conducted based on completely randomized block design with three replications in research greenhouse of faculty of agriculture, at ferdowsi university of mashhad in 2008. the first factor was competition between wild oat (densitie...