EFFECT OF NITROGEN SOURCES AND ASCORBIC ACID ON GROWTH AND ESSENTIAL OIL PRODUCTION OF GERANIUM (PELARGONIUM GRAVEOLENS, L.) PLANTS

The experiment was conducted during two successive seasons (2012/2013 and 2013/2014) in the nursery of ornamental plants and the Laboratory of Floriculture, Fac. of Agric., Minia Univ. The aim of this work is to study the effect of bio-mineral nitrogen and ascorbic acid (50, 100 and 150 ppm) on growth and essential oil production of geranium plants. Results showed that non-significant differences between mineral N (100%) and mineral N (75%) + Minia Azotein (Azotobacter strain) on growth and essential oil production of plants. The effect of high concentration (150 ppm) of ascorbic acid was superior to that other two concentrations (medium and low) on increasing plant growth and essential oil productivity. The plants fertilized with mineral N (75%) plus Minia Azotein (Azotobacter strain) and spraying with 150 ppm ascorbic were equal (growth and essential oil production) with plants received 100% N plus 150 ppm ascorbic acid.