in order to study effects of competitive weeds (sinapis arvensis, hordeum spp., secale montanum and agrostemma githago) on morphological traits, yield and harvest index of winter rapeseed (brassica napus l.) cultivars a factorial experiment was conducted in islamic azad university of tabriz, during 2007-2008. experimental factors were weeds controlling times included weeding in rosette (5-7 lea...

to investigate the effect of sowing density and growth habit on yield, yield components and weed community of red bean an experiment was conducted at research farm of zanjan university, during 2009. the experiment carried out using factorial-split plot design in completely randomized block arrangement with three replications. the main plots, included three red bean cultivars (goli, sayyad and d...

Whilst it is agreed that climate change will impact on the long-term interactions between crops and weeds, the results of this impact are far from clear. We suggest that a thorough understanding of weed dominance and weed interactions, depending on crop and weed ecosystems and crop sequences in the ecosystem, will be the key determining factor for successful weed management. Indeed, we claim th...

in order to study the effect of different redroot pigweed (amaranthus retroflexus) density on yield, yield components of soybean cultivar and determining competitive cultivar, a field experiment was carried out at mazandaran agricultural research station 2006. experiment was set up at a randomized complete block design with five rates of pigweed (0, 4, 8, 12 and 16 plant per square meter) and t...

Concerns exist that transgenic crop x weed hybrid populations will be more vigorous and competitive with crops compared with the parental weed species. Hydroponic, glasshouse, and field experiments were performed to evaluate the effects of introgression of Bacillus thuringiensis (Bt) cry1Ac and green fluorescent protein (GFP) transgenes on hybrid productivity and competitiveness in four experim...