Research Note : EFFECT OF NPK ON PLANT GROWTH AND FLOWERING OF Amaryllis belladonna Rohit Kumar Sharma 1 , S. Saravanan 1 and Sunita Kumari 2* 1 Department of Horticulture, Allahabad School of Agriculture, Sam Higginbottom Institute of Agriculture, Tech- nology and Sciences, Deemed to-be University, Allahabad, INDIA 2 Department of Horticulture, G. B. Pant University of Agriculture & Technology, Pantnagar-263 145, Uttarakhand, India *Corresponding Author’s E-mail: sunitakumari.sean@gmail.com ABSTRACT : The study on effect of NPK on plant growth and flowering of Amaryllis belladonna was carried out at Department of Horticulture, Allahabad School of Agriculture, SHIATS, Allahabad during 2013-2014. The study showed that at 180 DAP, application of N :P :K 125 50 125 Kg/ha resulted in significantly maximum plant height (43.96 cm) and No. of leaves/plant (8.66), too late flower scape emergence (174.66 days), tallest flower scape (51.76 cm), maximum diameter of flower bud (2.42 cm) and flowers (5.66) and longest durability of flower (6.55 days). The earliest flower scape emergence (167 days) was recorded in T 1 (N P K 60 30 30 kg/ha) while total number of flower scapes/plant (3.33) and number of flowers/scape (4.10) were found maximum in T 5 (N P K 75 45 45 Kg/ha) and T (N P K 5 175 75 175 Kg/ha) respectively. Keywords : Amaryllis belladonna, nitrogen, phosphorus, potassium, growth, flower, yield. Amaryllis, is a monotypic genus of Amaryllidaceae family, also known as the Belladonna Lily. The single species, Amaryllis belladonna is a native of South Africa, particularly the rocky southwest region near the Cape. It is often confused with the Hippeastrum, a flowering bulb commonly sold in the winter months for its propensity to bloom indoors. Amaryllis is suitable for planting in the beds, pot, rockery, shrubbery borders, green houses, garden and also in landscaping (Jana and Bose, 5). Being a new crop, its fertilizer management is not known (Sheela, 11). Most of the soils are deficient in major nutrients particularly N, P & K, so judicial application of these nutrients may play a good role in successful production of Amaryllis. Nitrogen (N) has the quickest and pronounced effect on the plant growth that ultimately leads to good yield. Nitrogen is the constituent of different amino acids, proteins and chlorophyll which is essential for good growth of plant. Nitrogen deficiency can be characterized by stunted growth and flowering may also be reduced (Seeley, 9). Phosphorus plays an important role in maintaining quality of the flower and is essentially required for the proper root growth. Potassium (K) is needed for healthy roots and stems, and aids plants with the respiration process (Niedziela et al., 8). Amaryllis plant can be grown at a relatively low phosphorus soil status without loss of yield and quality. Hence, the present study was conducted to investigate the optimum doses of nitrogen, phosphorus and potash required for better yield and quality of lower and bulbs production in Amaryllis lily. The experiment was laid out in a Randomized Complete Block Design with three replications at the Department of Horticulture, SHIATS, Allahabad during 2013-14. Nitrogen, phosphorus and potassium doses in 12 combinations (T 0 -control, T 1 -N :P :K 60 30 30 Kg/ha, T 2 -N :P :K 75 45 45 Kg/ha, T 3 - N :P :K 125 50 125 Kg/ha, T 4 -N :P :K 150 60 150 Kg/ha, T 5 -N :P :K 175 75 175 Kg/ha,T 6 -N :P :K 200 100 100 Kg/ha, T 7 -N :P 225 125 :K 225 Kg/ha, T 8 - N :P :K 250 150 250 Kg/ha, T 9 - N :P :K 300 200 300 Kg/ha, T 10 -N :P :K 325 225 325 Kg/ha and T 11 -N :P :K 350 250 350 Kg/ha) were tested on the Amaryllis belladonna. Nitrogen, phosphorus and potassium were applied in the form of Urea, Single Super Phosphate (SSP) and Muriate of Potash (MOP), respectively. Full dose of phosphorous, potassium and half dose of nitrogen was applied at the time of bulb planting and half dose of nitrogen was applied in two splits at 30 and 60 days after bulb planting. The plant growth and flowering attributes viz. plant height (cm), number of leaves/ plant, days required for scape emergence, number of scapes/plant, length of scape (cm), diameter of flower bud (cm), number of HortFlora Research Spectrum www.hortflorajournal.com Vol. 6, Issue 2; 131-133 (June 2017) ISSN: 2250-2823 Article’s History: Received:12-02-17; Revised:23-04-17; Accepted:22-05-2017 NAAS Rating : 3.78