Seed nanopriming with zinc oxide improves wheat growth and photosynthetic performance in wheat under drought stress

Abstract

Abstract Wheat is the most important cereal crop in the world. On the eve of climate and water scarcity, the use of different approaches such as the use of nutrients and organic or inorganic substances to increase drought tolerance and improve the yield in a wheat crop is necessary. The present study was conducted to cope with the problem of water deficit in wheat through ZnO nanoparticles (NPs). Wheat seeds (Ujala-16 and Zincol-16) were primed with different doses of ZnO NPs (40. 80, 120, and 160 ppm) under water deficit stress (No-stress and withholding water stress). Untreated seeds were also used as a control treatment. Results showed that drought stress decreased the shoot fresh (4.66 to 5.72 g) and dry weight (1.91g to 2.35g), shoot length (24.36 to 29.89 cm), root fresh (0.24 to 0.29 g) and dry weight (0.010 g) in both varieties of wheat. However, seed priming with ZnO at 80 and 120 ppm increased the fresh (8.07 to 10.09 g in Ujala-16 and 8.99 to 10.66 g in Zincole-16) and dry weight (3.31 to 4.14 g in Ujala-16 and 3.69 to 4.38 g in Zincole-16) of wheat plants. However, the maximum improvement in dry weight was observed under well-watered conditions (4.29 to 4.96 g in Ujala-16 and 4.62 to 5.45 g in Zincole-16). Similarly, ZnO NPs increased the chlorophyll a (1.73 mg/g FW in Ujala-16 and 1.75 mg/g FW in Zincole-16) b (0.70 mg/g FW in Ujala-16 and 0.71 mg/g FW in Zincole-16) and total chlorophyll content (2.43 mg/g FW in Ujala-16 and 2.46 mg/g FW in Zincole-16) in wheat by improving the activity of antioxidant and proline content of wheat. Similarly, plant nutrients such as Ca, Mg, Fe, N, P, K, and Zn contents increased in wheat plants after priming the seeds with ZnO NPs. Zincol-16 was responsive as compared to Ujala-16 however, ZnO NPs increase the growth and development of both wheat varieties under well-watered (control/No-stress) and withholding water stress. Thus, seed priming with ZnO NPs has the potential to alleviate the adverse effects of water deficits.