Print version ISSN 0100-8358
PARREIRA, M.C; ALVES, P.L.C.A and PENAHERRERA-COLINA, L.A. Weeds influence in common bean as a function of spacing and plant density. Planta daninha [online]. 2011, vol.29, n.4, pp. 761-769. ISSN 0100-8358. http://dx.doi.org/10.1590/S0100-83582011000400006.
Hypothesis is that reducing the density and the spacing between the lines, the period prior to the interference of weeds will be reduced by the bean crop. The aim of this study was to determine the period prior to weed interference (PPI) with the bean crop in terms of row spacing and population density. Treatments consisted of eight periods of weed coexistence with the crop: 0-10, 0-20, 0-30, 0-40, 0-50, 0-60, 0-70 and 0-80 days after crop emergence. The periods of coexistence were applied in two experiments, using two spacings, 0.45 and 0.60 m in two plant densities amounts per seed, 10 and 15 plants per meter. For each row spacing and seed density, the experimental design used was the randomized blocks, with four repetitions per treatment. Grain yield of the crop showed decreases of 16, 40, 36 and 58% when the coexistence with the weed was during all the cycle of the crop for row spacing of 0,45 m and seeding density of 10 and 15 plants per meter; and row spacing of 0,60 m and seeding density of 10 and 15 plants per meter, respectively. The period prior to weed interference (PPI) occurred in 28, 26, 22 e 14 days after crop emergence, respectively.
Keywords : Jaboticabal; Phaseolus vulgaris; plant density; grain yield.