The Effect of Trichoderma Isolates on Tomato Growth and Nutrients Uptake under Water Deficit Stress

Water shortage is one of the most important limiting factors for plant growth around the world. To cope with this phenomenon, several solutions have been proposed, including the use of microorganism with plant growth promoting traits such as Trichoderma. Accordingly, an experiment was conducted to investigate the effect of three fungal species on tomato growth factors, as well as nutrients uptake by the plant in water deficit stress conditions in a factorial arrangement based on randomized complete block design. Treatments including T1 (Trichoderma longibrachiatum KH), T2 (T. longibrachiatum MA), T3 (T. harzianum), NT1 (negative control - without fungi) and NT2 (positive control – without fungi and with chemical fertilizer) at three moisture levels consist of W0 (none stress), W1 (medium stress) and W2 (severe stress), performed in three replications. The results indicated that dry weight of shoot and root and nutrients’ uptake decreased in all treatments as water stress increased, but this reduction was significantly lower in fungal treatments. Under none stress condition (W0), T1 and T2 treatments increased N and P absorption and T3 fungal treatments increased Fe and Zn absorption significantly. By increasing stress conditions, most of the measured parameters of the plant in fungal treatments were reduced except for T1 treatment. Under severe stress condition (W2), T1 enhanced dry weight (32.8%), N uptake (62.7%), P (34.78%), Fe (39.3%) and Zn (47.6%), compared to negative control.