THE ABILITY OF SELECTED Trichoderma spp. TO IMPROVE WHEAT (Triticum asetivum L.) TOLERANCE UNDER HEAT, SALAINTY AND DROUGHT STRESSES THROUGH SEED TREATMENTS

Among ninety eight Trichoderma isolates obtained from plant rhizosphere and seeds of sixteen governorates in Egypt, a nine isolates were highly performed against heat, salinity and drought stresses under in vitro, and ex vivo experiments. The nine isolates were phenotypically characterized and identified by specific species primers which confirmed their species as five isolates of Trichoderma harzianum, three isolates of Trichoderma viride, and one isolate of Trichoderma virnes. The isolates NGB- T14, NGB-T20 and NGB- T33 were able to grow at 45ºC in in vitro, and the NGB-T14, NGB-T16, NGB-T17 and NGB-T18 showed a significant salinity tolerance up to 2M. While the NGB- T59, NGB T86 and NGB T90 were grown in 30% PEG for drought tolerance. The ex vivo pot treatments under abiotic stresses with selected isolates showed an enhancement in morphological and biochemical traits compared with the untreated seeds. In determination of the biochemical traits, proline and chlorophyll significantly increased under sever abiotic stresses. T. harzianum (NGB T14) alleviated the heat stress on plants to survive under 40°C. Also, T. harzianum (NGB T14) gave the best profile in high salinity levels. The isolate of T.viridi (NGB T59) were the best in drought tolerance. These observations may be of use to phytosanitary services for growers and agricultural researchers under the arid land for sustainable utilization.