Effects of benzyl adenine and potassium nitrate on some morpho-physiological traits of Narcissus (Narcissus tazetta L.)

Several plant growth regulators are used to improve the quality of cut flower in bulb plants, but their effectiveness depends on genotype and plant growth conditions such as nutrition status. A pot experiment was conducted under farm condition to study Benzyl Adenine (BA) and potassium nitrate interaction on floret diameter, stem diameter, flower height, flower number per bulb, fresh and dry weight of flower, cut flower vase life and soluble carbohydrates and proteins in leaves of Narcissus. Different levels of BA (0, 100, 200 and 500 mgl-1) were applied by two approaches of soaking bulbs for 24 hours before planting and spraying at early stages of inflorescence emerge. Potassium nitrate levels of (0, 1, 2 and 4 gKg-1 soil) were applied in two stages of trifoliate and swelling of the inflorescence among leaves as soil application. The results showed that all evaluated traits affected significantly by Benzyl Adenine treatments, which indicated Narcissus plants were positive sensitive to cytokinines. There were no statistically-significant difference between control plants and those undergoing potassium nitrate treatments in terms of flower number per bulb, fresh and dry weight of flower and cut flower vase life. Interaction of Benzyl Adenine and potassium nitrate at high levels caused significant increase in floret diameter, stem diameter, fresh and dry weight of flower, cut flower vase life, soluble carbohydrates and proteins. Results showed that the alteration in morphological and biochemical characters because of Benzyl Adenine and nitrogen positively affected cut flower quality of Narcissus.