Tuesday, November 14, 2006
154-1

Effect of maize (Zea mays) plant arrangement on weed and crop productivity.

Horacio A. Acciaresi, Maria S. Zuluaga, Marcelo Asborno, and Hugo O. Chidichimo. Facultad de Cs. Agrarias y Forestales (UNLP), CC 31, (1900) La Plata, Argentina

Uniform spatial pattern in maize (Zea mays) has been suggested as a technological alternative to obtain grain yield increases, due to a better use of resources. This technology could reduce intraspecific competition while favoring crop aggressiveness against weeds. The objective was to analyze the effect of maize row arrangement on crop grain yield and weed biomass. Field experiments were conducted during 2004/2005 and 2005/2006 growing seasons. Three maize hybrids with two-plant arrangement (0.70 and 0.35 m between rows) were tested. A greater photosynthetic photon flux density (PPFD) interception with a lower weed dry matter in regular row arrangement was obtained. Maize yield was greater in the regular plant arrangement than in the rectangular plant spacing. This increased crop yield was related to a better crop resource use that allows for an improved maize aggressivity against weeds. The use of an uniform spatial pattern appeared as an interesting alternative to increase both the crop yield potential and competitive ability against weeds in rainfed maize production systems