This work was carried out in the two successive seasons of 2016 and 2017 on five-year-old peach Florida prince cv. trees (Prunuspersica L.) grown in sandy silt soil at 3×5 m apart under drip irrigation system of a private peach orchard located at Belbies district, Sharkia Governorate, Egypt. The tested trees sprayed with nano-chitosan at 10, 20, 30 and 40 ppm, nano-silicon at 200, 400 and 600 ppm and potassium silicate at 1000, 2000 and 3000 ppm as well as water (control treatment). The results showed that spraying of nano-chitosan at all rates exhibited the highest TSS/acid ratio in the fruit juice without significant differences between them in the two seasons. Untreated trees had a highest vit. C content in fruits compared to other treatments. Also, 3000 ppm potassium silicate treatment gave the highest total sugars and carbohydrate percentages. The treatment of potassium silicate at 3000 ppm gained highest leaf mineral contents of N, P, K,Fe,Znand Mn, while,lowest leaf mineral contents of Fe, Zn and Mn were recorded with control and nanochitosan at 10 ppm.