Soil contamination with heavy metals may threat the sustainability of crop production, food safety and human health. It has been well documented that the use of microorganisms such as Trichoderma spp. can significantly ameliorate the heavy metals toxicity in soils and plants. This study investigated the efficiency of Trichoderma application on optimizing wheat (Morvarid cultivar) germination parameters under cadmium (Cd) and copper (Cu) nitrate toxicity at four levels (0, 50, 100 and 150 mg L

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... ). Through a completely randomized design with four replications using a factorial experiment. Some germination parameters such as germination percentage and germination rate, seed vigor index, germination index, seedling length, allometric coefficient (shoot to root ratio), fresh and dry weight of seedling were determined. The Results revealed the significant effect of Trichoderma on germination percentage (up to 10%), root length (up to 10%), seedling length (up to 15%), fresh and dry weights of seedling (nearly 12 and 11%, respectively). The application of Trichoderma in Cd contaminated treatments (up to 100 mg L -1 ) markedly improved wheat germination index (16, 10 and 12% respectively) and seedling length (5, 26 and 0.5% respectively). On the other hand, increasing the amount of Cu up to 50 mg L -1 in Trichoderma inoculation treatment resulted in higher germination index (20% compared to non-inoculated seeds) and seedling length (30% more than non-inoculated seeds). In conclusion, Trichoderma longibrachiatum could increase seedlings᾽ chance of surviving under heavy metals᾽ toxicity.