Effects of Nitrogen, Phosphorus and Potassium on Growth and Development of <I>Gladiolus hybrida</I>

Abstract

Effects of nitrogen, phosphorus and potassium levels on growth and development of Gladiolus hybrida cv. Spitfire were studied. The experiment consisted of 3 factors i.e: 1) three levels of nitrogen at 100, 200 and 300 mg/l, 2) two levels of phosphorus at 50 and 100 mg/l and 3) three levels of potassium at 50, 100 and 200 mg/l. The plants were supplied with 3 I of nutrient solution per m² (20 plants) twice a week. Other mineral elements were supplied at the same concentration in each treatment i.e. Mg 25, Ca 50, B 0.247, Mn 0.446, Zn 0.23, Cu 0.02, Mo 0.013 and Fe 0.611 mg/l. It was found that plants supplied with nitrogen concentration at 100 mg/l significantly promoted plant height, days from anthesis until senescence and number of cormels more than other treatments. Plants supplied with phosphorus concentration at 100 mg/l gave significantly higher result in plant height, number of florets per spike, fresh weight of corm and com diameter. The concentration of potassium did not affect plant growth. The result from this experiment indicated that the optimal concentrations of nitrogen, phosphorus and potassium in nutrient solution for gladiolus were 100, 100 and 50 mg/I respectively.