HOW THE GROWTH OF AMAZONIAN SPECIES OF HIGHT ETHNOBOTANICAL VALUE AFFECTED BY LIGHT STRESS?

The Amazon is a biome where in recent decades climate change has caused the increase in physiological plasticity of certain plant species. This plasticity characterized as resilience strategy of these species to environmental stress conditions such as light stress. The objective of this study was to evaluate the influence of shading on growth in height and leaf area of species Annona muricata L., Dipteryx odorata (Aubl.) Willd. AndCopaifera langsdorffiiDesf. The variables were TCA (Absolute Growth Rate) and TCR (Relative Growth Rate) in height and leaf area of young plants subject to the restriction of photosynthetically active radiation (PAR) for 4 months (50% light) and full sun in greenhouse conditions. Multivariate analysis jointly by the Hotelling showed significant differences (p <0, 0001) in height and leaf area beteween Graviola (soursoup), Cumaru (tonka bean) and Copaiba under two light levels. However, the Hotelling test specific to each species, showed that soursoup presented better growth rates in height and leaf area under 50% of light, the opposite was observed for Tonka bean (p = 0,0166 ). For Copaiba, rates of height growth were better to 100% of light and leaf area under 50% light. The Bartlett test showed similarity coefficient (phi = 68,01%) when the species were in full sun and dissimilarity (phi = 21,49%) under restriction. Regression analysis did not show a unique pattern of growth in different levels of shading, since the species plants have different strategies in their morphophysiological behavior when subjected to light stress.