We evaluated 64 lines and four cultivars of cowpea, in two different trials of planting density, under some environments of the São Francisco valley during the years 2004 and 2005, under rainfed and irrigated conditions, with the objective of identifying an adequate cowpea cultivar for the region. The trials were conducted in a randomized blocks design, with three replications, in two planting densities (100,000 and 200,000 plants/ha). Grain yield, genetic parameters, tolerance to some viruses, 100-grain weight, days for grain maturity and some cooking parameters were evaluated in both trials. A strong interaction genotype x environment was observed. The yield averages under irrigated conditions doubled the yield under rainfed grown conditions, for both densities. Some lines did not present virus symptoms, contrasting with the most damaged genotypes BR 17 Gurguéia and Canapu. The 100-grain weight was around 20.0 g in both planting densities. The 'Canapu' presented the highest value of grain water imbibing before cooking, differing significantly from all genotypes. Only the negative phenotypic correlations between percentage of grain water imbibing after cooking x expansion volume after cooking was significant. The line PC 95-05-12-2-2, which presented viruses notes close to one (without symptoms), grain yield higher than the mean, 100-grain weight around 24 g, broad stability, repeatability, and with attractive grain color and shape, was released as a new cowpea cultivar for region with the name of BRS Pujante.
Vigna unguiculata; cowpea; genotype x environment
