Respuesta fisiológica de especies arbóreas al anegamiento. Nuevo conocimiento sobre especies de interés en el arbolado urbano de Bogotá

Abstract

Los efectos del calentamiento global en las zonas urbanas hacen preponderante el estudio de especies arbóreas en diferentes condiciones de estrés abiótico, como el anegamiento. En este estudio se analizó el comportamiento fisiológico de seis especies nativas con cuatro niveles de anegamiento, determinando el estado hídrico, el comportamiento fotosintético y la pérdida de electrolitos. De acuerdo a los parámetros evaluados, se recomienda establecer Quercus humboldtii y Ficus tequendamae en zonas con altas precipitaciones y con tendencia al anegamiento debido a la tolerancia que se evidenció. Esto permite que estas zonas en Bogotá mantengan el arbolado urbano bajo escenarios de cambio climático. La estabilidad de las membranas celulares y la eficiencia máxima fotosintética del fotosistema II pueden ser usados como marcadores de tolerancia a condiciones de anegamiento en árboles.

Chlorophyll fluorescence and other physiological parameters as indicators of waterlogging and shadow stress in lulo (Solanum quitoense var. septentrionale) seedlings

“…The reduction of the RWC after 6 d of waterlogging was possibly caused by the low absorption and transfer of water to the leaves, negatively affecting cellular turgor (Moreno and Fischer, 2014) as caused by anoxia conditions in the root system (Moreno et al, 2019), a situation that can damage numerous metabolism processes in plants (Yan et al, 2018). Similarly, six tree species in Bogota constantly decreased their RWC with an increase in waterlogged time between 0 and 28 d (Moreno et al, 2019).…”

“…The reduction of the RWC after 6 d of waterlogging was possibly caused by the low absorption and transfer of water to the leaves, negatively affecting cellular turgor (Moreno and Fischer, 2014) as caused by anoxia conditions in the root system (Moreno et al, 2019), a situation that can damage numerous metabolism processes in plants (Yan et al, 2018). Similarly, six tree species in Bogota constantly decreased their RWC with an increase in waterlogged time between 0 and 28 d (Moreno et al, 2019). The plants with up to 3 d of waterlogging (DWA) without any influence on the RWC or recovery time may have activated mechanisms that diminished the water potential in the plant cells through the synthesis of compatible osmolytes, such as proline, soluble sugars, or glycine betaine in order to maintain a water potential gradient that favored water intake (Oh and Komatsu, 2015).…”

“…The strong decrease in the F v /F m ratio was especially evident in the plants with 9 d of waterlogging and 12 of recovery, with values below 0.7, which indicated severe stress that generated serious damage in PSII (Moreno et al, 2019) and showed, according to Ashraf (2012), the inability of the plants to regenerate Rubisco under these stressful conditions. In the other treatments, with levels that exceeded 0.7, the functioning of PSII was not impaired (Bansal et al, 2019); rather, there was a dynamic photoinhibition, without presenting real damage to the photosystems (Moreno et al, 2019).…”

“…Obviously, the flooding stress was increased by the conditions of shading, increasing the leakage of electrolytes, which is related to oxidative stress (Moreno et al, 2019). Similar results were found by Bansal et al (2019) in black beans, in which the membrane stability decreased as a result of the greater loss of electrolytes generated by the conditions of the lack of oxygen in the radical system (waterlogging for 10 d starting at 30 d after sowing), which was also manifested by cell membrane damage by ROSinduced peroxidation of membrane lipids (Andrade et al, 2018).…”

“…A reduction in the maximum quantum efficiency of PSII, when the condition of waterlogging stress is increased, is common in many different plant species (e.g. black beans, Bansal et al, 2019;pitanga, Mielke and Schaffer, 2010; and several tree species, Moreno et al, 2019). Most likely, the decrease in F v /F m in the flooded lulo indicated that it adversely affected the photochemistry of photosynthesis in these stressed plants (Mielke and Schaffer, 2010), while Janowiak et al (2002) observed tomato damage in the light-harvesting complex of PSII in waterlogged plants.…”