Development of cowpea (Vigna unguiculata (L.) Walp.) in different pot sizes

Cowpea is a crop of great economic and nutritional importance, used for human and animal consumption, particularly in semi-arid regions. Its growth and development depend on adequate conditions for the expansion of the root system and the establishment. Therefore, the objective of this study was to determine the effect of pot size on the shoot and root development of cowpea. The experiment was conducted in a greenhouse at the Department of Plant Science, Federal University of Ceará, in Fortaleza, Ceará, Brazil. Seeds of the Setentão variety were used in a completely randomized experimental design with five replications. The plants were grown in pots with volumes of 5, 11, 18, and 25 dm³, and shoot and root system traits were evaluated, including stem, leaves, pods, dry seeds, and roots. The data were subjected to analysis of variance and mean comparison tests, as well as correlation and principal component analyses. Pot size significantly influenced plant development and the most of the evaluated traits showed strong positive correlations, indicating a close interdependence between shoot and root system variables. Principal component analysis explained 65.7% of the total observed variation. Among the evaluated pot volumes, the 18 dm³ pot showed the best overall performance, considering vegetative, productive, and root traits, and is therefore recommended for cowpea studies and production under pot conditions.