in order to study the effects of different sowing dates by some of companion crops on the weeds control, morphological traits and yield of corn sc 504, a field experiment was carried out of research field at tabriz university during 2010 growing season. treatments were arranged in a factorial experiment using randomized complete blocks design with three replicatins. factors was include four lev...

wheat residues management and modification in tillage time are among suggested practices in weed control. to evaluate the effects of wheat residues and tillage time on weed dry matter and leaf area, corn dry matter and corn grain yield, a study was conducted at darab agriculture and natural resource college, shiraz university during growing season of 2008-2009. this experiment was conducted in ...

in order to evaluate competition among some weed species and canola, a field experiment in astan ghods razavi's field in mashhad was done on 2007-2008. thirty 50×50 cm quadrates were used in two times (stem and flower production) to measure the canola dry weight, leaf area index and canola and weeds density with destruction and thirty similar quadrates were used for counting weed species a...

In modern agriculture, with more emphasis on high input systems, weed problems are likely to increase and become more complex. With heightened awareness of adverse effects of herbicide residues on human health and environment and the evolution of herbicide-resistant weed biotypes, a significant focus within weed science has now shifted to the development of eco-friendly technologies with reduce...

Weed emergence timing: a new tool for managing weeds in crop fi elds The success of integrated weed management relies on matching control strategies to the specifi c weed problem in a fi eld. Managers must know not only which weed species (and how many) are present in a fi eld; they also must understand the distribution and development stages of these weeds throughout the fi eld. Weed control r...

in order to determine the critical period of weed control (cpwc) in corn (zea mays l.), an experiment was carried out in a randomized complete blocks design with 14 treatments and three replications during 2013 growing season in the nahavand climatic conditions. two series of the treatments including weed-free and weed-infested were applied in the regular time distances of 10, 20, 30, 40, 50 an...

in order to determine the practical method to predict economic production of wheat in competition with feral rye by using regression models, a factorial experiment was carried out based on randomized complete block design with three replications in dargaz. iran. experimental factors were included wheat cultivars (sayson, alvand, chamran and sepahan) and feral rye densities (0, 20, 40, 60 and 80...

Field experiments were conducted during the 2 year period from 2008 and 2009 to determine the effects of three seeding dates and seven weed control methods in DSR. The results suggested that seeding in the first week of July reduced weed density and biomass, increased kernel weight, leaf area index, and kernel yield compared to seeding rice in the first week of July. Amongst weed control method...

Weed infestations and associated yield losses require effective weed control measures in soybean and sugar beet. Besides chemical weed control, mechanical weeding plays an important role in integrated weed management systems. Field experiments were conducted at three locations for soybean in 2013 and 2014 and at four locations for sugar beet in 2014 to investigate if automatic steering technolo...

in order to evaluate the interference effect natural population weeds and plant density, an experiment with randomized complete block design in factorial arrangement with 4 replications was conducted in 2006 in a field experiment at ramin agricultural and natural resources university, khouzestan. treatments included two factor, plant density of corn at three levels (4, 7 and 10 plants m-2) and ...