Effect of phosphorus and potassium on the production and quality of cut rose cultivars

Abstract

Phosphorus and potassium are macro nutrients that play major role in growth and development of plants. A Randomize Complete Block Design experiment was laid with split plot arrangement at Ornamental Horticulture Nursery, Department of Horticulture, The University of Agriculture Peshawar during 2014 and 2015. Cut flower rose cultivars were tested with treatments of 3 levels of phosphorus (30, 60 and 90 kg ha-1) and potassium (20, 40 and 60 kg ha-1) each as well as combined. Results showed that when plants were supplied with phosphorus at 60 kg ha-1 and potassium at 40 kg ha-1, it significantly improved studied variables, such as early days to sprouting (11.5 days), days to flowering (35.0 days), maximum number of branches plant-1 (11.4), number of leaves branch-1 (19.0), flower stalk length (44.7 cm), flower diameter (7.7 cm), number of flower plant-1 (12.2), flower persistence (11.6 days) and survival percentage (96.8 %). Results further showed that all the study attributes were recorded significantly best in 2015 compared to 2014. In cultivars, Gold Medal produced early sprouting (12.7 days), maximum number of branches (7.4), and number of leaves branch-1 (15.3), survival percentage (87.1%), number of flowers (10.6) and flower persistence (9.2 days). While cultivar Cardinal produced highest flower stalk length (41.6 cm) and flower diameter (7.4 cm). The interaction between treatments and cultivars significantly affected number of branches plant-1, number of leaves branch-1, days to flowering, flower stalk length, flower diameter and flower persistence. It can be concluded that P @ 60 kg ha-1 with combination of K @ 40 kg ha-1 enhance production and quality of rose cultivar, especially in Gold Medal and Cardinal cultivars.