The effect of row spacing and weed density on yield loss of chickpea

Abstract
The adoption of no-till farming and the desire to maintain stubble cover when sowing legumes in northern New South Wales and southern Queensland have resulted in an increase in commercial row spacing for chickpea (Cicer arietinum L.). This paper examines the effects of increasing crop row widths on weed competition in chickpea crops. Weed densities of 0, 2, 4, 8, 16, and 32 plants/m2 of wild oats (Avena sterilis ssp. ludoviciana ) and turnip weed (Rapistrum rugosum) were established with chickpea crops planted with either 32�or 64�cm row configurations in northern New South Wales during 1996 and 1997. A rectangular hyperbolic model adequately represented the loss in chickpea yield with increasing density of either weed. Even low densities of