Qualidade de mudas de Ormosia arborea (Vell.) Harms produzidas sob diferentes condições de luminosidade e alagamento

Abstract

Ormosia arborea (Vell.) Harms is an arboreal species of wide occurrence, with characteristics typical of late secondary, it becomes indispensable actions that aim its propagation and conservation. The plants are exposed to several natural stressors, among them the water stress caused by the excess of water that limits the development of plants considered not adapted. Brightness is also an important factor influencing plant growth and development. Thus, two experiments were carried out to find answers on the emergence of seedlings under different light availability, as well as responses of the plants when submitted to flooding of the substrate associated with different light sources. Both experiments were performed with 30% and 70% shading in full sun. Destructive analyzes (growth measures and enzymatic analysis) and non destructive analyzes (gas exchange and chlorophyll fluorescence) were performed. O. arborea plants emerge more and less under shading levels (30 and 70%) and the seedlings present higher initial growth, gas exchange and photosynthetic efficiency of PS II when grown under 70% shading. Under flooding the flooded plants survived for 80 days and after the flooded period they present adaptive characteristics, such as hypertrophied lenticels. However, they reduce their photosynthetic potential and the quality of the seedlings. As with flooded treatments, the control treatment funn sun (C0) also proves to be inappropriate for the production of seedlings of this species.