Development of Gladiolus in function of nitrogen fertilization and corm diameter

Abstract

The Gladiolus is one of the most cultivated ornamental plants in Brazil, though there are few scientific information related to culture. The aim of this study was to evaluate the effect of nitrogen fertilization and corm size on growth and flowering of Gladiolus grandiflorus ‘San Remo’. The experiment was conducted in the area of Jardinocultura of Universidade Federal da Grande Dourados (UFGD) in Dourados - MS. The experimental design was completely randomized and the treatments in subplots, and the plot consisting of the diameters of the bulbs (large between 40 and 55 mm, medium between 20 and 40 mm and small than 10 mm) and the subplots of three nitrogen dose (30, 50 and 70 kg ha-1), with 10 repetitions. Evaluated the number of leaves, the leaves length, the beginning of flowering, the number of buttons per spike floral, the durability of the flower, the time of flowering and the number of cormilhos. The spikes produced were classified as Class III. Nitrogen fertilization was more efficient for the growth of corms medium and small size, with doses greater than 50 kg ha-1 provided better results. Corms large size and the aplication of 30 kg ha-1 nitrogen fertilization delayed the beginning of flowering. It is recommended to use medium-size corms and nitrogen fertilization of 50 kg ha-1 for the cultivation of Gladiolus gran­diflorus ‘San Remo’.