Caviglia, O.P.; Van Opstal, N.V.; Gregorutti, V.C., Melchiori, R.J.M.

CAVIGLIA, O.P.; VAN OPSTAL, N.V.; GREGORUTTI, V.C., MELCHIORI, R.J.M.

Congreso; IX Congreso Nacional de Maíz – Simposio Nacional de Sorgo; 2010

AIANBA

Nitrogen (N) and plant density in maize can affect canopy size and crop ability to capture and use the available resources (i.e. water and solar radiation). The objective of this work was to evaluate evapotranspiration (ET), radiation capture (RFAint), water- and radiation-use efficiencies (EUA and EUR, respectively). We tested the hypothesis that N and plant density affect RFAint, EUA and EUR without an evident impact in ET. Three experiments were carried out at Paraná, Argentina (31º50’S; 60 º31’ W). Treatments were a combination of two factors: N rate (0 and 200 kg N ha-1) and plant density (high, intermediate and low, A, M B, respectively). Densities were 4.0-4.5, 7.5 9.0-10.0 plants m-2 for A, M, and B, respectively. The interception of solar radiation and soil moisture (up to 1.2 m) were periodically recorded. Aboveground biomass and grain yield were measured at maturity. N and plant density affected canopy size, RFAint, EUA and EUR, whereas ET was not affected by factors. In the three years, yield was increased by N for 16-34% (P