Foliar application of chitosan improves plant biomass, physiological and biochemical attributes of rose (Gruss-an-Teplitz)

Rose is an important floricultural crop that has been exploited for many uses. It is important uses in different industries include, pharmaceutical, perfumery, and food industries that manifest higher flower yield. Therefore, response of Gruss-an-Taplitz to foliar application of chitosan (Ct) solution (0, 2.5, 5, 7.5, 10 mg L-¹), was evaluated in an experimental field. Ct treatment had significant effects on studied parameters, including plant growth, pigments, enzymes, and gaseous exchange. This experiment was laid out under Randomized Complete Block Design (RCBD) using three replications per treatment. Ct (7.5 mg L-¹) significantly improved growth, in terms of higher leaf area (20.37%), plant height (20.19 %), number of flowers (55.51%), flower weight (34.64%) and flower diameter (33.78%) as well as enhancing relative water contents (27.38%) with respect to control. Chlorophyll a (54.60%), Chlorophyll b (12.13%), Carotenoid (8.36%) and anthocyanins (17.09%) were also increased at 7.5 mg L-¹ Ct, which showed higher photosynthetic pigments as compared to control. Consequently, Ct (7.5 mg L-¹) treated plants showed higher enzymatic activity; CAT (9.94%), SOD (83.87%), POD (64.54%), total antioxidant (35.48%), phenolics (7.41%) and gaseous exchange; Pn (55.65%), E (31.76 %), gs (18.38%) and Ci (34.17%) that improved the plant growth and productivity of Gruss-an-Taplitz. Foliar application of 7.5 mg L-¹ Ct improved biomass, water preservation, pigments, enzymatic activity, leaf gaseous exchange, and quality of Gruss-an-Taplitz plants.