Article
Spanish
ID: <
rcV8YeY40d6JepKwMaFoO>
Abstract
Plant flooding inhibits water absorption, causes static closure and reduces photosynthetic rate (A). In tolerant species, these physiological responses are reversed over time. In a seasonally flooded forest in Brazil, we proposed to validate a model to explain the initial responses and acclimatisation to flooding of different plant species. The first response observed was the static closure, which appeared to be caused by an increase in the xylematic content and foliar of abscisic acid (ABA). The decrease in static conductance (g s) was accompanied by a decrease in the photosynthetic rate (A), a decrease in the relative static limitation of photosynthesis (Ls) and an increase in the relative mesophylar limitation (Lm). In the peak of flooding A and GS, the values of drained plants were taken up. Although a decrease in the concentration of intercellular CO2 (Ci) product of A decrease may cause chronic photoinhibition, no decreases in the potential quantum yield of PSII (Fv/Fm) were found. Increases in Lm with decrease in Ls suggest that the static closure was not the main cause of the reduction of A, which was accompanied by a decrease in the total soluble protein content (PST), an indirect measure of the rubial content. At times of peak flooding, all variables that had changed due to the rise in water took over the values of drained plants, indicating acclimatisation to this environment.