Effects of Different Levels and Combinations of Nitrogen and Potassium Content in the Seed Oil of Castor bean (Ricinus communis L.) irrigated with sewage and raw water treaty.

A mamoneira (Ricinus communi Linn) à uma planta bem adaptada Ãs condiÃÃes de semi-aridez, sendo considerada um grande potencial econÃmico para a RegiÃo Nordeste. A irrigaÃÃo com esgoto domÃstico tratado Ã, tambÃm, considerada uma alternativa para as regiÃes com escassez hÃdrica, devido ser uma fonte de Ãgua para essas regiÃes, alÃm de proporcionar economia de fertilizantes. O Ãleo extraÃdo das sementes da mamona, apÃs o processo de esterificaÃÃo, pode ser utilizado como biodiesel. O objetivo desse trabalho foi avaliar a potencialidade do uso de esgoto sanitÃrio tratado em lagoas de estabilizaÃÃo na irrigaÃÃo da mamona, mediante a utilizaÃÃo de diferentes nÃveis e combinaÃÃes de macronutrientes (NitrogÃnio e PotÃssio) aplicados na adubaÃÃo, e verificar o teor de Ãleo nas sementes produzidas. O experimento foi realizado em uma Ãrea anexa à EstaÃÃo de Tratamento de Esgotos da Cidade de Aquiraz, na RegiÃo Metropolitana de Fortaleza. A cultivar da mamona foi a BRS 149 Nordestina, a qual foi irrigada com Ãgua de poÃo e esgoto domÃstico tratado por lagoas de estabilizaÃÃo, pelo sistema de microaspersÃo. O experimento teve duraÃÃo de 8 (oito) meses, janeiro a agosto de 2007. Foram implantadas duas Ãreas distintas: Ãrea para irrigaÃÃo com Ãgua de poÃo (1.320m2), e Ãrea destinada à irrigaÃÃo com esgoto tratado (1.277,25m2). Cada Ãrea possuÃa 04 blocos, 04 repetiÃÃes. As repetiÃÃes constavam de 17 parcelas, com 06 plantas. As parcelas foram numeradas de 1 a 17, indicando o tipo de adubaÃÃo a ser aplicada. A adubaÃÃo dos tratamentos variaram segundo as quantidades de NitrogÃnio (00, 30, 60, 90 Kg/ha) e PotÃssio (00, 30, 60, 90 Kg/ha). Avaliaram-se a influÃncia da irrigaÃÃo com esgoto domÃstico tratado na produtividade e na produÃÃo do Ãleo nos diversos tratamentos. Em geral, nÃo houve diferenÃas significativas. A produtividade foi influenciada pela adubaÃÃo nitrogenada, na qual as maiores produtividades foram obtidas para o tratamento N2K2. As maiores percentagem de Ãleo durante a irrigaÃÃo com efluente tratado foram 60,78 e 61,22 %, obtidas, respectivamente, para os tratamentos N1K2 e N3K2, enquanto que para os tratamentos irrigados com Ãgua as maiores percentagens de Ãleo foram 61,27 e 60,89, obtidas, respectivamente, para os tratamentos N0K2 e N2K2.The castor bean (Ricinus communis Linn) is a plant well adapted to conditions of semi-arid and is considered a great economic potential for the Northeast Region. Irrigation with treated domestic sewage is also considered an alternative for those areas with water shortages due to be a source of water for these areas, while providing savings in fertilizer. The oil extracted from the seeds of the castor oil, after the process of esterification, can be used as biodiesel. The aim of this study was to evaluate the potential use of treated sewage into the stabilization ponds for irrigation of castor oil, using different levels and combinations of nutrients (nitrogen and potassium) fertilizer applied in, and check the oil content in seeds produced. The experiment was conducted in an area annexed to the treatment of sewage from the city of Aquiraz, in the metropolitan region of Fortaleza. A cultivar of castor oil was the BRS Nordestina 149, which was irrigated with well water and domestic sewage treated by the stabilization ponds, and micro system. The experiment lasted for 8 (eight) months from January to August 2007. Were implanted two distinct areas: area for irrigation with water from pool (1.320m2), and area for the irrigation with treated sewage (1277.25 m2). Each area had 04 blocks, 04 repetitions. The repetition appeared on 17 plots, with 06 plants. The plots are numbered from 1 to 17, indicating the type of fertilizer to be applied. The fertilization of the treatments varied according to the quantities of nitrogen (00, 30, 60, 90 kg / ha) and potassium (00, 30, 60, 90 kg / ha). The influence of irrigation with treated domestic sewage on productivity and production of oil in various treatments. Overall, there were no significant differences. The yield was influenced by nitrogen fertilization, in which the greatest yields were obtained for the treatment N2K2. The highest percentage of oil during irrigation with treated effluent were 60.78 and 61.22%, obtained respectively, for treatments N1K2 and N3K2, while for the treatments irrigated with water the highest percentages of oil were 61.27 and 60.89, obtained respectively, for treatments N0K2 and N2K2