Productivity of Dry Grains of Cowpea [Vigna unguiculata (L.)] Creole Cultivar (Canupum), as a Function of Different Planting Densities

Aims: Cowpea [Vigna unguiculata (L.)] is a legume of great importance, being a source of food rich in protein, being essential for human nutrition and produced during the rainy season in the semi-arid region of Brazil. In this sense, the objective was to study the efficiency of different planting densities on cowpea productivity in the Brazilian semi-arid region.

Place of Study: The experiment was conducted from September to December 2021 at the Rafael Fernandes experimental farm, in the district of Alagoinha (5º03'37 "S, 37º23'50" W), northwest of Mossoró, State of Rio Grande do Norte, Brazil,

Study Design and Methodology: The experimental design used was randomized complete blocks with five treatments (1.0; 2.0; 3.0, 4.0 and 5.0 plants hole-1) with four replications. Each plot consisted of dimensions of 3.5 m x 4.8 m, with six rows of 4.8 m in length, with a total area of 18.2 m2, with the useful area being the four central rows, with dimensions of 2.8 x 4.8 m, with an area of 13.44 m2, for collecting dry grains.

Agronomic Characteristics of Cowpea [Vigna unguiculata (L.)]: Number of pods, expressed in units ha-1 (NV), length of pods, expressed in cm (CPV), weight of one hundred grains, expressed in grams (P100G), dry grain productivity, expressed in kg ha-1 (PG), number of grains pod-1, expressed in units (GV), dry grain index, expressed in percentage (IGS) and pod production, expressed in grams (PV) of cowpea, Creole cultivar (canapum).

Conclusions: The highest grain productivity was influenced by planting densities, with the density of 3.4 plants per pit being the one that resulted in the highest productivity (409.78 kg ha-1). For the characteristic weight of 100 dry grains, the density of one plant per hole was the one that promoted the highest average weight with a maximum value of 28.24 g.

For farmers who cultivate in a family farming system, a planting density of three plants per hole is recommended.