Morphological and Physiological Characteristics Which Enhance Competitiveness of Winter Wheat {Triticum Aestivum) Against Goldbachia Laevigata

To study the competition potential of six winter wheat genotypes against the weed goldhachia laevigata, two field experiments were conducted at the weed research station of the plant pest & disease research institute, karaj, iran, during two growing seasons from 2000 to 2002. the six wheat genotypes used in this study were 6618, m-75-15, m-75-13, alamout, qafqaz and m-75-5. the experiments were arranged in a randomized complete block design with a factorial arrangement of treatments and with four replicates. 6618 and m-75-5 showed the highest and lowest competitive potential with the weed, respectively. the genotypes with higher competitive potential were characterized as having better canopy height, total of fertile tillers, increased leaf area index, an increase in cumulative total dry matter, increased crop growth rate and relative growth rate. these criteria can be used in plant breeding programs to screen for more competitive wheat genotypes against g. laevigata.