NÍVEIS CRÍTICOS DE FÓSFORO EM MILHO CULTIVADO EM SOLOS DE DIFERENTES MINERALOGIAS

• Main Authors: FÁBIO BROGGI, ALEXANDRE CAMPELO DE OLIVEIRA, FERNANDO JOSÉ FREIRE, EMÍDIO CANTÍDIO ALMEIDA DE OLIVEIRA, ALEXANDRE TAVARES DA ROCHA, MARIA BETÂNIA GALVÃO DOS SANTOS FREIRE
• Format: Article
• Language: English
• Published: Universidade Federal Rural do Semi-Árido 2014-01-01
• Series: Revista Caatinga
• Online Access: http://www.redalyc.org/articulo.oa?id=237132753020

The P critical levels in plants depend from soil characteristics which reflect phosphate buffer power. In Pernambuco, soils mineralogical characteristics change at different regions where corn is cultivated. To evaluate P critical levels in corn plants in soil cultivated in different soils and contact periods of this element in the soil, aiming to study the relationships between these critical levels and P adsorption, it was realized an experiment using subsuperficial samples of a Vertissolo Ebânico órtico (VEo) (Mollisol), clay textured with predominance of 2:1 clay mineral and a Nitossolo Vermelho distroférrico (NVdf) (Nitosol), high clay content, predominantly hematitic, colleted at the semi - arid and humid regions of Pernambuco State, Brazil, respectively. The P doses were defined in function of the levels 0; 0.2; 0.4; 0.8 and 1.0 from the P Maximum Capacity of Adsorption (CMAP) of each soil and were incubated by 90; 60; 30; 15; and 0.5 days. The experiment was real- ized into a greenhouse in a factorial scheme (5x5x2), five P levels, five incubation periods and two soils, in randomized blocks delineation with three replicates each. Corn plants were more efficient to utilize P in NVdf, the soil with higher CMAP. The corn shoot critical levels decreased in accordance to the period of incubation in VEo, the soil with lower CMAP.