Desenvolvimento do feijoeiro submetido ao estresse por déficit hídrico

Abstract

The cultivation of this crop in our region is carried out predominantly under the rainfed regime, where the irregularity of rains and high temperatures has contributed considerably to the water deficit and, consequently, reduction and / or total loss of production. Although this type of bean is considered a species adapted to drought, this adaptation varies within the species. The objective of this research is to identify how to grow cowpea (Vigna unguiculata L) more tolerant to water stress. This work was developed with four varieties (Corujinha, Macaíba Branca, Roxinho and Sempre Verde), these are the most planted in the State of Paraíba. The present experiment was carried out under greenhouse conditions. The treatments resulted from the combination of the four cowpea cultivars with four available water values (AD1 = 40, AD2 = 60, AD3 = 80 and AD4 = 100% of the crop evapotranspiration - ETc), throughout the cycle of culture. The experimental design was randomized blocks in a 4 x 4 factorial scheme, with three replications, totaling 16 treatments and 48 plots. Plant height, stem diameter, number of leaves, leaf area, aerial phytomass and root phytomass were evaluated. The “cultivar” and “water deficit” effects were evaluated in a factorial scheme through analysis of variance with the “F” test. Polynomial regression analysis was performed on the factor “water deficit”, as it is a quantitative factor, in order to explain, through mathematical models, the effect of water deficit on each variable studied. Regarding the factor “cultivars”, as it is qualitative, the Tukey test was applied to compare the averages. The water depths applied significantly influenced the cultivars, the height of the plants, the diameter of the stem, the number of leaves, the leaf area and the phytomass of the aerial part. The cultivar roxinho presented the highest averages in most of their parameters.