the effects of mycorrhiza symbiosis in increased tolerance to drought stress in wheat

to evaluate the effects of mycorrhiza symbiosis in increased tolerance to drought stress in wheat (triticum aestivum) an outdoor greenhouse experiment was conducted at islamic azad university, sabzevar branch in 2012-2013. experiment was conducted as factorial arrangement in a randomized complete block design with three replications. factors were: mycorrhiza fungi type (glomus mosseae, glomus intraradices and non-inoculated) and drought stress as water withholding at different wheat growth stages (full irrigation, water withholding at stem elongation, water withholding at flowering and water withholding in seed filing stage). the result showed that yield components such as plant height, fertile tiller number and spike number were not affected by mycorrhiza fungi symbiosis and there was no significant difference between mycorrhiza fungi symbiosis and control. the highest biological and economic yield was observed in g. mosseae symbiosis that had not significant difference with g. intradicese. water withholding at seed filling had the most negative effect on 1000 seeds weight, biological and economic yield, water withholding at flowering stage had the mainly negative effect on seed per spike and water withholding at stem elongation had the highest negative effect on tiller per plant. overall, mycorrhiza symbiosis decreased drought stress affect on wheat yield and g. mosseae was better than g. intradicese.