Effect of drought stress and foliar application of iron oxide nanoparticles on grain yield, ion content and photosynthetic pigments in sesame (Sesamum indicum L.)

In order to study the effects of drought stress and foliar application of iron oxide nanoparticles on sesame plants, a field experiment was laid in Faculty of Agriculture, University of Shahrood in 2014. The design of experiment was in split plot with blocks completely randomized in three replicates. Drought stress, W1=7, W2=12 and W3=17 irrigation time, were randomized in main plots with four concentrations of foliar application of iron oxide nanoparticles, F1 = 0, F2 = 0.5, F3 = 1 and F4 = 1.5 kg at 1000 l water, in sub-plots. Results showed that the interaction between drought stress andiron oxide nanoparticles had significant effect on grain yield, biomass, leafstomatal conductance, chlorophyll "b" and carotenoids content in leaves, and seed nitrogen. The results indicated that the highest grain yield and biomass were obtained at W1F3, stomatal conductance at W1F2, chlorophyll "b" at W1F4, carotenoids at W2F3 and seed nitrogen at the W3F3 treatments. Moreover, the number of branches per plant and the concentration of potassium in seeds were significantly affected by both treatments. However, phosphorus in seeds, and potassium and phosphorous in leaves remained unchanged under treatments. Number of seeds and seed weight per capsule decreased about 12.3 and 27.7%, respectively by worsening the drought condition from W1 to W3. In general, it can be stated that in the drought stress condition, foliar application of iron oxide nanoparticles about 1 kg per thousand liters of water improves the physiological characteristics of sesame and grain yield.