Evaluation of Weed Tolerance and Competition Indices of 18 Wheat Genotypes

Choosing varieties with high weed competitiveness is important in integrated weed management (IWM). This experiment was carried out in order to study weed tolerance and competition indices of 18 wheat genotypes under natural weed interference or without interference at the research field of agricultural faculty, University of Mohaghegh Ardabili, during 2010-2011 growing season. Significant differences were found in the indexes of wheat genotypes. Stress tolerance index of genotypes was between 110.3 to 915.0 kg ha-1. More tolerance indices such as Mean Productivity, Harmonic index and Weed Interference Tolerance Index were higher for N-80-19 and Alvand genotypes and lower for Dabira and Toos than others. Among the tolerance indices, weed interference tolerance index (WITI) and ability of weed competition (AWC) were more efficient to classify wheat genotypes to weed tolerance. Alvand and C-85-9 genotypes had the highest competitive index (CI). This finding can be used for non-chemical weed management programs.