Efficiency in the use of phosphorus by cowpea genotypes

Abstract

Cowpea (Vigna unguiculata (L.) Walp.) is an edible legume with good ability to fix nitrogen and not demanding soil fertility. However, some genotypes may have a greater ability to utilize the nutrients available in the soil for their growth. Thus, the objective of this work was to evaluate the efficiency of phosphorus (P) use in genotypes of cowpea. The experiment was conducted in the field and the experimental design was a randomized complete block design with four replicates arranged in a 2 x 5 factorial scheme. The treatments consisted of two P doses (0 and 60 kg ha^-1 of P₂O₅) and five bean genotypes (Paulistinha, BRS Xiquexique, Pingo de Ouro, Corujinha, and Costela de Vaca). Each plot was formed by four plant rows, measuring 3.0 m in length, spaced 1.0 x 0.3 m, and with two plants per hole. The genotypes responded significantly to the increase in P levels in the soil, with increases in the number of seeds per pod, number of pods per plant, productivity, dry mass, and plant P accumulation. "BRS Xiquexique" was efficient and responsive, and it could be indicated as the most appropriate for cultivation in the region. "Corujinha" is the most suitable cultivar for production in high levels of P among the creole genotypes evaluated. "Costela de Vaca" and "Paulistinha" can be indicated for low P production in the soil. low P production.