Cowpea (Vigna unguiculata (L.) Walp.) is the most important grain crop in the Brazilian semi-arid region. The objective of this work was to evaluate eighteen genotypes under irrigated and rainfed conditions in Petrolina, PE, and Juazeiro, BA, Brazil, in the years of 1995, 1996, 1997 and 1998.The experiment consisted of two trials, which were replicated five times in a randomized block design, with four replications. The grain yields corrected to ideal stand by covariance were analyzed by different statistical procedures. Variations in soil fertility, crop management and rainfall average were enough (P<0.01) to modify the grain yield of the genotypes. The Balinha genotype, selected and maintained by small farmers, showed better yield performance, 1,779 kg/ha, under irrigation conditions than traditional cultivars recommended by research centers. Under rainfed conditions, the results showed good genotypes, like EPACE 10 cultivar and TE 901781F line, with 1,343 kg/ha and 1,176 kg/ha, respectively. EPACE 11, with 1,497 kg/ha, showed good performance under both conditions. All results showed that it is necessary to develop specific genotypes for different environments and social conditions, with special focus on irrigated conditions.
Vigna unguiculata; genotype environment interaction; adaptation; grain; yields
