بررسي آثار رقابت چندگونه اي علفهاي هرز بر عملكرد و اجزاي عملكرد گندم در منطقه شيروان

Evaluation effects of multispecies competition of weeds on wheat yield and its components in Shirvan area

Field experiment was conducted in 2002 at Shirvan area to evaluate multispecies competition of weeds with winter wheat (Triticum aestivum) and its effects on wheat yield and its components. Sampling was done by a quadrate (50cm * 50cm)ʹ randomly. To determine effective weeds on wheat yieldʹ 1/W and 1/LnW regression models showed better fit to data. Results showed that despite presence of Avena ludoviciana " Erysimum cheiranthoides,Polygonum avicular Rapistrum rugosumʹ Chenopodium album, Salsola kali, and Sonchus sp. in the fieldʹ only Avena ludoviciana, Salsola kali, and Rapistrum rugosum had significant reduction effects on wheat yield and reduced number of fertile tiller and number of seed per m2 but had no effect on 1000-seed weight and harvest index.