Physiological responses in cowpea varieties under different levels of shading

Abstract

The Brazilian Northeast present awide diversity of species cultivated by small and medium farmers, among these is the cowpea or cowpea [Vigna unguiculata (L.)Walp.]. How is a region of high level of solar radiation variations directly affect the growth and development of plants. The aimof this study was to evaluate the influence of solar radiation on the vegetative growth of cowpea cultivars, BRS Acauã and BRSPujante under different levels of shading. Plants of these varieties were grown in polyethylene pots (12 L) and were subjectedto the following shading levels: 0 (full sunlight), 30, 50 and 70% retention of sunlight. The parameters evaluated were: plantheight and diameter, chlorophyll a and b, photosynthesis, stomatal conductance, transpiration, fresh and dry matter. From theresults obtained, it can be stated that shading favors the vegetative growth of cowpea varieties, with the restriction level of solarradiation by 50% and 70% respectively ideal for BRS Acauã and BRS Pujante.