Pesquisa Agropecuária Brasileira
Print version ISSN 0100-204X
BEZERRA, Antônio Aécio de Carvalho; TAVORA, Francisco José Alves Fernandes; FREIRE FILHO, Francisco Rodrigues and RIBEIRO, Valdenir Queiroz. Canopy and yield characteristics of a bunch-type cowpea under different population densities. Pesq. agropec. bras. [online]. 2009, vol.44, n.10, pp. 1239-1245. ISSN 0100-204X. http://dx.doi.org/10.1590/S0100-204X2009001000005.
The objective of this study was to evaluate the effects of different population densities on the morphologic characteristics and grain yield of a modern bunch-type cowpea line [Vigna unguiculata (L.) Walp.]. The experiment was carried out in 2002, in a randomized block design, with a factorial arrangement 3x5, with three between-row spacings (0.4, 0.5 and 0.6 m) with five plant populations (105, 2x105, 3x105, 4x105, and 5x105 plants ha-1), and four replicates. There were no significant interactions among the factors for any of the characters. The number of nodes in the main stem, number of seeds per pod, and the weight of 100 seeds were not significantly influenced by row spacing and plant populations. Increases in the population density caused significant reductions in the number of lateral branches, number of pods per plant, and grain yield per plant. There was an increase of 16,7% in grain yield from the population of 100 thousand to the 500 thousand plants per hectare. The different arrangements of cowpea plants promoted changes in the morphology, yield components, and grain yield.
Keywords : Vigna unguiculata; row spacing; stand; grain yield.