Evaluation of the effect of foliar and soil application of zinc and silicon nanoparticles on some physiological traits of rice (Oryza sativa L.)

To evaluate the effect of various application methods of zinc (Zn) and silicon (Si) on some physiological traits of rice (cv. Tarom Hashemi), a field experiment was carried out as factorial based on randomized complete block design with 16 treatments and three replications in Nour in 2016. The experimental treatments included T1: Control, T2: Calcium silicate soil application, T3: Zinc sulfate soil application, T4: Calcium silicate Zinc sulfate, T5: Nano-Si foliar application, T6: Nano-Si Calcium silicate, T7: Nano-Si Zinc sulfate, T8: Nano-Si Calcium silicate Zinc sulfate, T9: Nano-Zn oxide foliar application, T10: Nano-Zn oxide Calcium silicate, T11: Nano-Zn oxide Zinc sulfate, T12: Nano-Zn oxide Calcium silicate Zinc sulfate, T13: Nano-Si Nano-Zn oxide, T14: Nano-Si Nano-Zn oxide Calcium silicate, T15: Nano-Si Nano-Zn oxide Zinc sulfate and T16: Nano-Si Nano-Zn oxide Calcium silicate Zinc sulfate. Results showed that straw protein, zinc and silicon in grain and straw were affected by experimental treatments, but the evaluated treatments showed no significant effect on grain protein and chlorophyll content of flag leaf. Among evaluated treatments, the combined application of silicon and zinc improved nutrient absorption compared to separate application of each element and control. This indicates the aggregation of Zn and Si compounds and their synergistic effects. Combined application of silicon and zinc by both methods of NP foliar application and soil application (T16) improved nutrients uptake in grain and straw of rice, but among the methods used, the NP foliar application had a more positive effects in improving physiological characteristics of rice plants than the treatments of soil application of elements.