Componentes de produção de genótipos de feijão macassar sob lâminas de irrigação.

Abstract

The cowpea has economic importance, social and to feed. However, the Brazilian semiarid region presents water limitations for cultivation. Thus, it is important to identify genotypes and efficient irrigation leveis. The objective was to study the components of production of cowpea genotypes under irrigation leveis, checking the tolerance to water stress and efficiency in water use. The experiment was carried out in the field, in the municipality of Pombal, PB, under semi-arid climate conditions. The experimental design was a randomized blocks, in a factorial 4 x 5, for four cowpea genotypes (Costela de Vaca, Pingo de Ouro, Paulistinha and BRS Marataoã) and ave irrigation leveis with (40, 60, 80, 100 and 120% of evapotranspiration real- ETr) in four replications. Data were evaluated by analysis of variance. We evaluated the characteristics length, mass and number of pod beans, number of pods per plant, production and efficiency in water use. There was a significant interaction between all factors, except for mass with grains per pod and number of pods per plant. The Costela de Vaca and Pingo de Ouro are not suitable for mechanical harvestingl The BRS Marataoã did not change the physical characteristics of the pods in function of irrigation, with acceptable performance in blade 230,69mml The Costela de Vaca genotype cow and Paulistinha were more productive, with satisfactory yield with application 162,84mml The genotype Pingo de Ouro is lesa productive under water restrictionl The Paulistinha was tolerant the most water scarcity , increasing efficiency in water use in decreasing the applied blade.