effects of foliar and fertigation based calcium nitrate applications on growth, flower quality, and postharvest physiology of roses in a soilless system

This study investigated the effects of foliar and fertigation-based calcium nitrate applications on growth, flower quality, and postharvest physiology of two rosa hybrida cultivars ('samurai' and 'jumilia') grown in a soilless system. treatments included a control (10% of the recommended ca level), foliar spraying, and fertigation, arranged in a factorial design with four replications. the experiment was conducted in a greenhouse at the faculty of agriculture, ferdowsi university, mashhad, iran. results revealed that root morphological characteristics such as length and volume were maximized in the 'jumilia' cultivar when calcium nitrate was supplied via fertigation. conversely, foliar spraying with calcium nitrate markedly improved shoot and floral characteristics. compared to the control, foliar calcium nitrate increased flower diameter by 15.4%, enhanced hip length by 14.25 cm, and increased hip diameter in the 'samurai' cultivar by 18.76%. moreover, foliar application of calcium nitrate extended the vase life of cut roses to about 10 days by preserving higher relative fresh weight. antioxidant enzyme activities were also enhanced under foliar treatment in the 'samurai' cultivar, with superoxide dismutase (sod), catalase (cat), and peroxidase (pod) increasing by 53.84%, 75.71%, and 97.28%, respectively. additionally, foliar-sprayed 'samurai' plants showed nearly double calcium accumulation in leaves and petals. interestingly, in the 'jumilia' cultivar, foliar application reduced leaf zinc content by 68.87%, while simultaneously enhancing leaf magnesium concentration by 64.16%. overall, foliar supplementation with calcium nitrate proved to be a practical strategy for improving flower quality, enhancing antioxidant defense, and prolonging vase life of roses in soilless culture.