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 ...

The compositions of the germinable weed seedbank and aboveground weed communities in a long-term tillage and rotation study were characterized 4, 5, and 6 yr (2002 to 2004) after the adoption of glyphosate-tolerant corn and soybean. Averaged across rotation, mean germinable weed seed density and diversity were greatest in the no-tillage treatment as compared to the minimumand conventional-tilla...

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....

in order to investigate the effects of common lambsquarters (chenopodium album l.) competition on corn (zea mays l.) morphological and physiological characteristics, an experiment was conducted in 2005-2006 at the research station of agricultural faculty, ferdowsi university of mashhad, iran. the experimental design was split plot based on randomized complete block design (rcbd) with three repl...

to evaluate the effect of combined use of different soil tillage methods and weed control on cotton yield, a split plot experiment based on randomized complete block design was conducted at the city of boshruyeh in 2012. experiment factors were tillage method as main-plots with three levels, including conventional tillage, no-till system and minimum tillage; and different methods of weed contro...

in order to evaluate the effects of intercropping of maize- peanut, weeding and their planting design on weed population dynamics, an experiment was conducted as a factorial experiment in the form of rcbd with three replications at the research farm of agriculture center of zabol university (iran) in 2012. the treatments including sowing system in four levels as first factor  (sole maize, sole ...

abstract improving nitrogen use efficiency (nue) is an important objective of the agroecosystem management. a field experiment was conducted to study the effect of different competition patterns on nitrogen balance in the wheat agroecosystem. experimental design was split–plot based on randomized complete blocks with four replications. the main plots consisted of different nitrogen rates (i.e. ...

Redroot pigweed is one of the injurious agricultural weeds on a worldwide basis. Understanding of its interference impact in crop field will provide useful information for weed control programs. The effects of redroot pigweed on cotton at densities of 0, 0.125, 0.25, 0.5, 1, 2, 4, and 8 plants m(-1) of row were evaluated in field experiments conducted in 2013 and 2014 at Institute of Cotton Res...

In order to evaluate the impact of crop residues (zero, 25 and 50%) and nitrogen (zero, 125 and 250 kg ha) on weed seed bank and potato yield, two-years research was conducted as a split plot arranged in randomized complete block design in Rozveh Agriculture Research Station, Freidan-Esfahan. Numbers of weed species in seed bank, aboveground, and both seed bank and aboveground were 1, 2 and...