Competition limits of the yield components of the common bean ‘BRS Ártico’ with white grains

Abstract

The objective of this study was to determine the limits of competition of yield components and ideal plant popula­tion for the common bean cultivar BRS Ártico, with white grains. Five plant populations, resulting from the sowing of 7, 10, 13, 16 and 19 seeds per meter, were compared in an experiment conducted at Embrapa Rice and Beans, in the autumn-winter season of 2015, with an experimental design of randomized blocks with four replica­tions. The yield was broken down into three components, number of plants ha^-1 (NP), number of grains per plant (NGP) and grain weight (GW). An upper boundary curve, formed by a horizontal line and a hyperbola, was defined for each component as a function of the NP. The later the competition limit is determined in the cycle, the lower is its value, being equal to 190,000, 140,000 and 125,000 plants ha^-1, respectively, for number of pods per plant, NGP and GW. The maximum possible yield increases with NP to the lowest competition limit, 125,000 plants ha^-1, and after, there are adjustments between successive components, stabilizing this yield regardless of NP.