The feeding rose flower (Rosa hybrid L. cv. Grian Bdprex) with Ammonium Fertilizers by Cultan method compared with nitrate fed plants

Nitrogen fertilizers are one of the most important factors in the production of greenhouse rose flower. Nitrate and ammonium are main mineral nitrogen sources, that can be absorbed by higher plants roots. Plants can absorb both nitrate and ammonium ions, but some of species are not able to have an optimum growth with ammonium as a sole nitrogen source. The form and application of fertilizers not only affect nitrogen uptake but also improve the absorption of other nutrients. In this research, the effect of form of nitrogen and application of sulfuric acid on growth and some nutrient elements absorption was investigated by rose plants ( Rosa hybrid L. cv. Grian Bdprex). With attention to alkalinity soil in most of agricultural area in Iran, aims of this research was determination of the best fertilizer and its application method for this area and increasing of elements absorption by plant and practical recommendation for rose producers. The experiment was carried out as completely randomized design with 5 treatments and 4 replications. Treatments were organic fertilizer sulfuric acid ammonium sulfate, organic fertilizer sulfuric acid calcium nitrate, organic fertilizer calcium nitrate distilled water, organic fertilizer ammonium sulfate distilled water and control (without fertilizer or acid water). Examined plants were 3-years-old rose cv Grian Bdprex. Plants irrigated every 4 days and used soil was clay loam. The results showed that, nutrition with Cultan method that was combination of organic fertilizers, ammonium, and sulfuric acid, in soil with high pH, led to an increase in vegetative growth (leaf fresh and dry weight, flower fresh and dry weight, stem fresh and dry weight, root fresh and dry weight, flower stem length) flower diameter, vise life, chlorophyll a, carotenoids and nitrogen, potassium and iron elements concentrations, and a decrease in zinc concentration in the plant. For instance, 85 percent increase was observed in leaf dry weight at nitrate calcium acid treated plants compared to control. Application of nitrate fertilizer with acid in comparison with nitrate fertilizer increased vegetative growth, flower quality, iron, nitrogen and potassium elements concentration, but decreased Zn element concentration. Therefore, we concluded that due to positive effect of Cultan method on growth, nutrient concentration, chlorophyll a, rose flower yield, and vase life of cut flowers, this method could be used for growing rose flower ( Rosa hybrid L. cv. Grian Bdprex), especially in soils with high pH.