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 ...

Seed production of annual weeds persisting through cropping phases replenishes/establishes viable seed banks from which these weeds will continue to interfere with crop production. Harvest weed seed control (HWSC) systems are now viewed as an effective means of interrupting this process by targeting mature weed seed, preventing seed bank inputs. However, the efficacy of these systems is directl...

this research was carried out in the research field of aboureyhan campus, university of tehran during 2006-07 growing season to investigate the effect of sinapis arvensis l. interference on yield and growth indexes of different canola (brassica napus l.) varieties. the experimental design was a complete randomized block arrangement in factorial with three replications. eight canola varieties na...

Weed interference results in increased synthesis of reactive oxygen species (ROS). High accumulation ROS causes oxidative stress and stimulates the activation antioxidant defense system plants. biotic form allelochemicals abiotic competition for plants which inhibition growth development Ageratum conyzoides is an annual weed plantations can cause on surrounding This study aims to determine effe...

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...