in order to compare of ecological management of weed control on economical income, yield and yield components of cotton (gossypium hirsutum l.), a randomized complete block design with 12 treatments and four replications was conducted in mahvelat of khorasan razavi province, iran. treatments consisted of weeding, harrowing, burning, two times weeding, weeding + harrowing, weeding + burning, har...

abstract in order to evaluate of yield and yield components of eight wheat cultivars against flix weed (descurainia sophia), an experiment was conducted using a factorial arrangement of treatments in a randomized complete block design with four replications during 2003-2004 growing season in varamin region. the wheat cultivars were tabasi, roshan, karaj2, azadi, niknejad, mahdavi, shiraz and pi...

within-field variation of wheat yield and spatial pattern of weed density and soil nitrogen were evaluated by geostatistical methods. samples were taken from a 90×120 m area located in a 3.8 ha wheat field. soil nitrogen content and weed density at tillering and wheat yield at maturity were measured in 1 m2 plots located at the center of 10×10 m grids. grain yield was varied between 1.5-4.9 t h...

in order to investigate the effects of weeds interference on yield and yield components of different genotypes of common bean, an experiment was conducted as split plot based on randomized complete block design with three replications at agricultural research station of tabriz university, in 2011. the main plots were eight genotypes of different types of common bean including red bean, (cv. gho...

abstract to study the effect of nitrogen application and 2-4-d on weed density and weed architecture in winter wheat an experiment was conducted at agricultural research site, university of mohaghegh ardabili, ardabil in 2009. treatments were two nitrogen levels (no fertilizer and 150 kgnha-1 application) with or without 2-4-d (1.5 kg ai ha-1). results showed that nitrogen application had no si...

sowing date is the most important factor in physiological and morphological characteristics with positive effects on plants. to evaluate the effect of sowing date and weed interference on yield and yield components of red beans cultivars a factorial split plot experiment in randomized complete block design with three replications was carried out in the research field of zanjan university. main ...

To assess the effect of non chemical management of weed control on forage Sorghum (Sorghum bicolor) a field study was conducted in Varamin, Iran during 2010 crop year in a three- replicated- split factorial experiment laid out in randomized complete block design with four weeding levels (W1= one time cultivation at 3-leaf stage using a duck foot cultivator, W2<...

Good management models for postemergence weed control require good estimates of which weed density produces an economic threshold yield. Because intraweed competition increases if weeds are aggregated, weed spatial pattern may be an important factor for inclusion in management models. Mathematical models of weed–crop competition have demonstrated that this may be the case, but the small number ...