Evapotranspiração, adubação e densidade de plantas de helicônia irrigada por microaspersão em cultivo protegido.

Abstract

: A research was carried out from September/03 to March/04 in greenhouse conditions with 50% shading, at EMBRAPA Experimental Station, in Paraipaba, CE, with the target of to assess the behavior of Heliconia psittacorum L x H. spathocircinada (Arist), Alan Carle s variety, by sprinkler irrigation system, in greenhouse conditions, facing different levels of fertilization and plants density. The irrigations were accomplished every time that the matrix potential reached 10 kPa. The crop evapotranspiration was determined by the soil-water budget for a 0,60m depth. The deep drainage and capillary rise were determined by the Buckingham-Darcy s model. Soil water storage variance was determined by the Reichardt equation (1985). The Doorenbos and Kassan model (1979) was used to determine crop coefficient, kc, at initial, crop development and blooming stages. In order to analyze density of plants were used 5,000; 6,600 and 10,000 plants/ha. In relation to fertilization s levels there was no statistical difference at 5% probability level. There was no influence in plants height by the spacing. The density of 5,000 plants in combination with fertilization level 3 showed average value of 7.9 leaves/plants. The values of crop coefficient for initial, crop development and blooming stages were 0.29; 0.60 and 0.92 respectively.