بررسي جنبه هاي رقابتي گندم و علف هاي هرز خانواده شب بو: 1- ساختار كانوپي

Study of competition aspects of wheat and weeds from cruciferʹs family:I-Canopy architecture

In order to determine effects of weed competition on canopy architecture of wheat, an experiment was conducted in Mashhad, 2001 and 2002. The treatments included three Cruciferʹs family weeds (Wild mustard. Turnip weed and Flix weed) and five levels of weed density (control, 4, 8, 16 and 32 plants/m2 for tviId musturd and turnip weed, and control, 16, 32, 64 and 128 plant/m2 for Flix weed). Randomized complete block design with four replications in an additive series technique was employed as the experimental design. An ANOVA procedure indicated significant effects of wild mustard and turnip weed on plant height.. leaf area and leaf distribution of wheat. Increasing weed plant density, reduced the height and leaf area of wheat. In addition, in comparison with control, leaf area of wheat was more distributed in the upper part of the canopy. As plant density of weeds increased, their plant height also increased and more leaf area was measured in the upper part of weeds conopy.