Effect of Cotton (Gossypium hirsutum L.) and Common lambsquarters (Chenopodium album L.) Densities on Yield and Yield Components of Cotton

In order to evaluate the effect of cotton (Gossypium hirsutum) and common lambsquarters (Chenopodium album) densities on yield and yield components of cotton, a field experiment was conducted in the Agricultural Research station in Birjand University, Iran. A factorial experiment was carried out in a complete block design with three replications. Treatments included weed density (0, 6, 9, 12 plants.m-2) and crop density (6, 9, 12 plants.m-2). Three pure stand of common lambsquarter densities (6, 9, 12 plants.m-2) was added to each block. Results indicated that there was a significant decrease in yield and yield components of cotton under weed densities. Six plants.m-2 of weed caused 15% decrease in seed cotton and increase of weed density up to 9 and 12 plants/m2 caused further decrease in seed cotton. These weed densities (6, 9 and 12 plants.m-2) caused 16, 30 and 45% decrease in cotton seeds respectively. Lint yield was decreased 13, 24 and 42% as weed density increased from 6 plants.m-2 to 9 and 12 respectively. In this experiment, increasing cotton density was able to soften the negative impact of increasing weed density. Increasing crop density can be utilized effectively to minimize cotton yield reduction due to weed interference.