Lonchocarpus cultratus (Vell.) A.V.G. Azevedo & H.C. Lima (Fabaceae) growth under different shade and water availability conditions

Abstract

Light and water availability are among the environmental factors that most influence plant growth and development. The ability to acclimate to shade and tolerate drought can be assessed by growth characteristics. Thus, the objective of this study was to analyze the effect of water availability and shading on the initial growth of Lonchocarpus cultratus, a tree species, common name ‘embira-de-sapo’, abundant in several areas of South and Southeastern Brazil. The experiment was arranged in a 3x2 factorial completely randomized design. The plants were kept under 0%, 50%, and 80% shading and two conditions of water availability (daily irrigation - ID and twice a week - NDI). The variables height, root length, dry biomass of leaves, stem, and root were evaluated at 30, 60 and 90 days after emergence (DAE). Total, a, and b chlorophyll, mycorrhizal colonization, and nodulation were determined. Death of young plants maintained at 0% NDI occurred at the beginning of growth. At 90 DAE, plants kept under 80% shading and ID showed the highest height and etiolated plants due to the reduction of light intensity in this treatment. Over the experimental period, 0% and 50% shaded plants irrigated daily had the highest percentage of mycorrhizal colonization, and nodulation was observed in all plants regardless of the treatment.