INFLUENCE OF NITROGEN AND PHOSPHORUS FERTILIZERS WITH NITROGEN SOURCES ON FLORAL PARAMETERS OF TUBEROSE (Polianthes tuberosa L.)

An experiment was laid out during two consecutive years in Horticulture garden of Chandra Shekhar Azad University of Agriculture and Technology Kanpur. There were three nitrogenous sources viz. urea, ammonium sulphate and calcium ammonium nitrate, four levels of nitrogen viz. 0, 50,100 and 150 kg/ha and four levels of phosphorus viz. 0,100,200 and 300 kg/ha, thus a total of fourty treatments were taken. The results showed that emergence of spike under the influence of N sources ranged from 97.27-98.35 and 95.58-97.91 days during first and second year of study. Calcium ammonium nitrate caused 1.08 and 2.33 days earlier spike emergence than urea treatment. Nitrogen applied@ 150kg/ha proved more effective in delaying spike emergence but 300kg/ha phosphorus induced earliest emergence. Length and width of spikes was improved with ammonium sulphate followed by CAN recorded 78.19 and 80.99 cm long and 0.88 and 0.90 cm thick spikes, respectively. Nitrogen applied @150 kg/ha caused 78.16 and 81.14 cm length of spike and 0.88 and 0.89 cm thick spikes in first and second year, respectively. Length of rachis was registered 1.45 and 1.65 cm longer under ammonium sulphate. 150 kg nitrogen per hectare maximized length of rachis (26.74,27.85 cm) whereas, phosphorus @ 300kg/ha revealed maximum (26.26 and 27.38 cm) length of rachis. Number of flower maximum influenced by CAN revealed 39.69 and 40.83 flowers during both years.Nitrogen @ 150kg/ha maximized (40.80 and 41.20) number of flowers. Fertilization with calcium ammonium nitrate exhibited longest blossoming duration. Durability of spike increased consistently with increase in nitrogen levels up to 150/ha dose recording 21.41, 22.39 days duration during both experimental years. Phosphrous @ 200kg pro longed self life by 3.46 and 2.67 days when compared with control registering 20.89 and 22.33 days durability.