LAUSR

Abstract Miniature rose (Rosa chinensis) is an ornamental and commercial plant having many applications, especially in green space design. One of the major environmental factors limiting the cultivation of this plant is salinity. This study investigated the effect of silicon application on the morphological and physiological responses of miniature rose under the salinity stress conditions in 2018. A factorial experiment was conducted in a completely randomized design with three replications. Experimental factors were including the salinity (0, 3 and 6 m mos/m) and silicone fertilizer (0, 250, 500 and 1000 mg/L nano silicon, 250, 500 and 1000 mg/L potassium silicate). The results indicated that salinity stress leads to a significant reduction in the plant height, leaf area, vase life, fresh weight of the plant, number of flowers, stem diameter, peduncle, open flower diameter, flower life on plants and chlorophyll a and b concentrations. Under the salinity of 6 dS/m without applying silicon, the activity of glutathione reductase and superoxide dismutase enzymes was 2.44 and 2.25 fold with respect to the control, respectively. Upon applying the silicon treatment, the concentration decrement of potassium, phosphorous, iron and zinc was reduced in the shoots of rose. Application of potassium silicate and nano silicon at concentrations of 1000 mg/L had the greatest effect on the improvement of studied traits. Therefore, adding the silicate fertilizers to saline soils can reduce the negative effects of salinity stress on the miniature rose plant var. minima.