The effect of silicon on the growth, evapotranspiration, and the reproductive yield of the Persian petunia (Petunia hybrida)

Silicon is a non-essential element with several reported beneficial effects on various crops. For investigating the growth and reproductive yield of the Persian Petunia, a factorial experiment with a completely randomized design was conducted at 4 levels of Si (0, 50, 100 and 150 ppm), during two stages of growth (4-6 and 8-10 leaf) with 4 replications. The experiment was carried out under the greenhouse conditions. Silicon was applied via foliar spray once every two weeks. The application of Si increased the number of the flowers on plants up to 73%. An increase was also observed in the height of the plants under the effects of Silicon and the stage of growth. Although the application of Si foliar spray increased the fresh, dry, and biomass weights during both stages of growth, these weight parameters were generally higher in plants which received Si treatment within 4-6 leaf stage. The fresh and dry weights as well as leaf surface area increased 57, 37 and 52% and leaves‟ evapotranspiration reduced up to 53% using Si, respectively. In conclusion, it can be claimed that the application of Silicon can increase the total biomass weight by reducing plant‟s evapotranspiration and increasing leaf‟s surface area, which in effect results in an increase in the number of the flowers per plant.