Fontes e doses de nitrogênio para mamoneira de porte baixo no sistema plantio direto

Abstract

IVFontes e doses de nitrogênio para mamoneira de porte baixo no sistema plantio direto Nitrogen fertilizers and rates in castor bean hybrids under no-till system

Content of Nitrogen, Phosphorus and Potassium in Castor Bean Irrigated With Saline Water and Doses of Nitrogen

“…equal to 0.6 dS m -1 ; and 6.3 to 11.2 g kg -1 when irrigated with higher water salinity (4.6 dS m -1 ) consisting of increase per unit increase of ECw 14.2 and 11.0% for TN and TP, respectively. These trends are similar to Moro et al (2012) when evaluating different sources of nitrogen in fertilizers in the cultivation of hybrid Savannah; the authors found phosphorus content in shoots between 2.7 to 3.3 g kg -1 . Severino et al (2008) in a study with BRS Northeastern observed phosphorus content in plant tissue ranging from 2.9 to 10.6g kg -1 , using different substrates.…”

“…From this point on, increases to the highest level saline were observed, where TK obtained in the leaves was 45.3 g kg -1 . Crusciol et al (2012) evaluated the extraction and exportation of macronutrients by Savannah castor hybrid and they found at 97 days after emergence, 9.9 g kg -1 of K during the 2005/2006 season and 10.6 g kg -1 of K in the 2006 harvest at 100 days after emergence. The reduction in potassium absorption is possibly related to the increased concentration of sodium in root, through inhibiting the absorption of potassium due to the competitive relationship between these cations (Kawasaki et al, 1983); as well as it is associated with competition for uptake at the level of membrane sites (Bloom & Epstein, 2006).…”