Resumo

ACEVEDO BARONA, Marco A et al. EFFECTS OF PLANTING DENSITY AND NITROGEN FERTILIZATION ON THE GRAIN YIELD OF RICE CULTIVAR CENTAURO IN VENEZUELA ¹. Agronomía Trop. [online]. 2011, vol.61, n.1, pp.15-26. ISSN 0002-192X.

In order to evaluate the effect of planting density and nitrogen fertilization on the grain yield, Oryza sativa L. of CENTAURO, trials were established during the 2006- 2007 irrigation cycle in the three main production areas of the country. The design was a randomized complete block arranged in stripes, the (DN) is located in the main plots and (Ds) in the secondary plots with three replications. grain yield was evaluated in kg ha^-1, adjusted to 12% moisture. Analyses of variance were conducted individual and group, Tukey mean analysis and multivariate analysis of principal components. The analysis individually and group by location allowed to detect significant differences (P ≤ 0.01) for DN in all locations and significant differences Ds in Barinas, DNxDs interaction was highly significant in Barinas and guarico, while in portuguesa it was not detected possibly due to high experimental variation. All these results suggest that the cultivar cENTAURo presents a differential response to nitrogen application (120 ≤ DN ≤ 200) kg ha^-1 for grain yield. The group analysis the sources of variation in DN, Loc, DNxDs and DNxLoc were significant at 1% and 5%, respectively. The variation is predominance in the locations, followed by DNxloc, DN and DNxDs. It was found that the principal components analysis and the use of dual representations (Biplot) are useful for studying the interaction of both factors (DNxDs

Palavras-chave : Oryza sativa L; agricultural mana gement; nitrogen; planting density; cultivar CENTAURO.