effect of flaming on wild mustard (sinapis arvensis l.) soil seed bank, soil micro organisms and physicochemical characteristics

in order to study the effect of flaming on seed viability of sinapis arvensis l., changes in microorganisms population and physicochemical characteristics of soil after canola (brassica napus l.) harvesting, an experiment was carried out based on randomized complete block design with four replications and eight treatments at karaj research center, iran, during 2005- 2006. after harvesting canola at the end of spring, wild mustard seeds were distributed evenly on the surface of the soil. in some plots, canola stubbles were left on the ground and in some plots canola stubbles were taken off. under this condition, the following treatments were applied: flaming under wet and dry soil condition, burning stubbles under wet and dry soil condition. in other plots canola stubbles were taken off the plots and then flaming was applied under wet and dry soil conditions. check plots did not receive any treatment. results indicated that all treatments reduced seed viability, and the highest loss in seedling density occurred in the flaming treatment on dry-soil. flaming did not have any serious affect on soil microorganisms or on its other physiochemical aspects, however dry-soil treatments proved the safest.