Titanium dioxide nanoparticles (TiO2-NPs) enhance drought tolerance and grain yield of sweet corn (Zea mays L.) under deficit irrigation regimes

Among environmental stresses, drought is the main limiting factor of crop yield. The use of nanomaterials has been considered a strategy to enhance the drought tolerance of plants. To evaluate the beneficial effect of titanium dioxide nanoparticles (TiO 2 -NPs; 0 (T 0 ), 50 (T 50 ), and 100 (T 100 ) mg l −1 ) and deficit irrigation (70 as control (I 70 ), 105 (I 105 ), and 140 (I 140 ) mm evaporation from Class A evaporation pan) on drought tolerance of sweet corn cv. chase, an open field experiment was performed in 2018–2019. The results showed that deficit irrigation decreased the maximum efficiency of PSII ( F v /F m ), but T 50 improved F v /F m . 50 mg l −1 TiO 2 -NPs enhanced leaf SOD, APX, and CAT antioxidant activities by 17%, 10%, and 24%, respectively, over the control. I 140 T 50 increased leaf proline content 8% and 17% over I 140 T 0 and I 140 T 100 , respectively. Grain number per ear with the highest correlation with grain yield ( r = 0.97) was the most determining grain yield component. The greatest grain yield was obtained from I 0 T 50 and I 105 T 50 (760 and 809 g m −2 , respectively). Therefore, I 105, due to less water consumption, and T 50 may be considered to produce sweet corn with a desired performance under water-limited conditions.