ECOPHYSIOLOGY OF THE TREE SPECIES Cedrela fissilis Vell. (Meliaceae) SUBMITTED TO FLOODING

Abstract

ECOPHYSIOLOGY OF THE TREE SPECIESCedrela fi ssilis Vell. (Meliaceae) SUBMITTED TO FLOODING ROCHA, G. A.; ROMANATTI, P. V.; OLIVEIRA, F. M.; CUNHA NETO, A. R.; PEREIRA, F. J.; POLO, M. Ecophysiology of the tree species Cedrela fi ssilis Vell. (Meliaceae) submitted to fl ooding. CERNE, v. 24, n. 4, p. 323-333, 2018. HIGHLIGHTSCedrela fi ssilis trees survived in all treatments due to a marked development of cortical intercellular spaces in fl ooded plants The stem periderm thickness was reduced by fl oodingThe superoxide dismutase activity was decreased, but the activities of the ascorbate perioxidases and catalase in the leaves were increased.Young Cedrela fi ssilis trees partially tolerate fl ooding since they developed ecophysiological changes in order to survive in this condition. ABSTRACTSoil water saturation requires different adaptative strategies by tree species that live under such conditions. We aimed to study the responses that ensure fl ooding tolerance by tree species and so provide support for recovery projects with degraded areas subject to fl ooding. We evaluated the ecophysiology of Cedrela fi ssilis under different water saturations, including anatomical traits, gas exchange parameters, antioxidant system analysis and growth. We subjected 100 day-old plants to three treatments: Control (FC) where the substrate was kept at fi eld capacity; Flooded Roots (FR), where the substrate remained submerged but with no surface layer of water, and Flooded Stem (FS), with a water layer accumulation of around 3.0 cm over the substrate, fl ooding part of the stems. The plants were kept under such conditions for 90 days. Plants survived in all treatments due to a marked development of cortical intercellular spaces in fl ooded plants. However, photosynthesis and other gaseous exchange were limited under FR and FS treatments. In addition, the periderm thickness was reduce by fl ooding and there was an accumulation of starch grains in the parenchyma cells of the xylem, cortex and pith of the stem. There was also a signifi cant lipid peroxidation on the leaves under FR and FS treatments. The superoxide dismutase activity was decreased, but the activities of the ascorbate perioxidases and catalase in the leaves were increased. We concluded that young Cedrela fi ssilis plants partially tolerate fl ooding since they developed ecophysiological changes in order to survive in this condition. Consequently, this species is a good candidate for the reforestation projects in environments where intermittent fl ooding occurs, such as riverside and riparian forests. v.24 n.4 2018 ECOPHYSIOLOGY OF THE TREE SPECIES Cedrela fissilis VELL. (MELIACEAE) SUBMITTED TO FLOODING 324 CERNE ROCHA et al.

Does silicon inEugenia myrcianthes Nied. seedlings under water stress contribute in the tolerance and recovery?

“…The behavior of E. myrcianthes seedlings can be attributed in our research to the plasticity of the seedlings and the perception of the stress environment. Phenotypic plasticity can be determined as the advantage that a species has in response to a changing environment, being adaptive when it reaches similar or higher values for a given physiological trait in relation to its initial environment, without abiotic stresses (Becklin et ssilis, under seasonal ooding (Rocha et al 2018). E. myrcianthes seedlings under water stress (de cit and ooding) showed sensitivity of the photosynthetic apparatus, with regard to the photochemistry of photosynthesis, it is important to highlight that, after periods of water stress, the plants reached recommended values and close to their respective controls, showing once again the physiological plasticity of the species.…”