The objective of this experiment was to evaluate the effect of different plant populations and row spacing on dry matter accumulation, grain yield and yield components of irrigated drybean. The experiment was conducted during the 1997/98 growing season in the experimental field of the Rural Engineering Department of the Federal University of Santa Maria, Santa Maria - RS, Brayl. The cultivar BR-FEPAGRO 44 - Guapo brilhante, (type II) was submitted to three plant populations (175, 250 and 325 thousand plants há-1) and three row spacing (35, 50 and 65cm). A factorial completely randomized design was used with four replications. Sprinüer irrigations were appiied when maximum crop evapofranspiration, determined based on class A evaporation pan, indicated na accumulated value of 25mm. Results demonstrated that the different plant populations and row spacing did not affect grain yield and grain weight. However, the number ofseeds per legume and legumes per plant increased as plant population decreased. The reduction in row spacing increased shoot dry matter during grain filling period. The cultivar BR-FEPAGRO 44 - Guapo brilhante presented great plasticity of grain yield components mainly because the reduction in plant population resulted in higher grain yield of individual plants.
irrigation; crop system; drybean; evapotranspiration
