Manejo da adubação potássica e da irrigação localizada na cultura do pinhão manso no cerrado

• Autor(a) principal: Costa, Fernando Rezende da
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/5051
• topic: Manejo de irrigação; Nutrição de plantas; Déficit hídrico; Biocombustível; Irrigation management; Plant nutrition; Water deficit; Biofuel; ENGENHARIA DE AGUA E SOLO::IRRIGACAO E DRENAGEM

The cultivation of jatropha is attracting great interest for the production of biodiesel. Despite irrigation and fertilization contribute to the better development of the culture, few research has been done about this. So the objective of this study was to evaluate the effect of irrigation levels and dose of potassium fertilization on the growth of aerial part and seed productivity of jatropha, and levels of irrigation on the distribution of roots of culture. The experiment was conducted in the experimental area of the School of Agronomy from Federal University of Goiás, during the period of two years. Was evaluation twelve of epochs respectively in the first and second agricultural year, in intervals of thirty days, coinciding with the dates of the characteristics evaluated. In evaluating the growth of the aerial part of the culture, the treatments consisted of four levels of irrigation, being: N0 = rainfed (control), N40 = 40% of Class A pan evaporation (ECA), N80 = 80% ECA, and N120 = 120% ECA, four rates of potassium fertilization: K40 = 40 kg ha-1 K2O, K80 = 80 kg ha-1 K2O; K120 = 120 kg ha-1 K2O, and K160 = 160 kg ha-1 K2O, based on the first year of fertilization. For analysis of seed productivity of jatropha, used the same irrigation treatments and potassium fertilizer used in the analysis of growth the aerial part. Already the system root was evaluating by monolith methodology in the treatments with 80 kg ha-1 of K2O to four levels of irrigation, sampled in three depth: 0- 25, 25-50 e 50-100 cm in five position in relation the stem of culture. The design was a randomized block with four replications. The irrigation system used was microsprinkler with frequency the irrigation to three times of week, by Monday, Wednesday and Fryday. Was evaluated the following parameters of crop growth culture: plant height, crown projection area, stem diameter, number of branches in the main branch and root distribution. Potassium fertilizer and irrigation levels promoted significant increase in the parameters of vegetative growth of plants jatropha grown in the Cerrado. The level medium the irrigation of 115% to ECA and 125 kg ha-1 to K2O, was showed the best result, but the levels of irrigation not influenced the root density the jatrophas plant cultivate in Cerrado the plant roots tended to be distributed in the topsoil and near the emitter. The effective root depth of jatropha is 0.50 m. The applied rates of potassium fertilization did not affect the seed yield of jatropha, while the irrigation level of 67% ECA maximized productivity, reaching 658 kg ha-1.