TEMPORAL VARIATION OF THE TOTAL PHENOLIC COMPOUNDS CONCENTRATION IN Vochysia divergens Pohl. (VOCHYSIACEAE) LEAVES IN THE BRAZILIAN PANTANAL

Abstract

The total phenol concentration present in Vochysia divergens Pohl. (Vochysiaceae) leaves in the Pantanal was analyzed. Work was carried out between September/2012 and June/2013 which is made up by the dry season (September/2012), the beginning of the rising water (December/2012), the high water (March/2013) followed by the receding water period (June/2013). For the purpose of the research fifteen trees were selected, five from each sample area. The phenolic content in the leaves was obtained from the samples which were dried, steeped with ethanol: water and centrifuged. The extract was used to determine the concentration of total phenols using the Folin-Ciocalteu spectrometric method. There was no difference among the sampling areas; however the values were different in relation to seasonal periods. The lowest concentration was recorded in the dry season (young leaves) increasing gradually at the beginning of the rising water, with higher levels at the end of high water and receding water season. The highest concentration of phenols occurred during the receding water period (end of the life cycle of V. divergens leaves), followed by high and rising water periods. The increase in phenol concentration is associated with the Pantanal flood cycle, and related to the phenology of the V. divergens leaves.

Canopy Ant Assemblage (Hymenoptera: Formicidae) in Two Vegetation Formations in the Northern Brazilian Pantanal

“…Variations in plant phenology are directly related to the availability of food resources for ants, considering, for example, the increase of these resources during fruiting and flowering events, as well as the reduction in leaf fall and renewal periods (Basset et al, 2003;Castaño-Meneses, 2014). Besides this the phenology of V. divergens depends on the Pantanal's hydrological regime, with flowering during the dry period, fruiting during the rising water and high water periods, and foliage renewal during the receding water and dry periods (Nunes-da- Cunha & Junk, 2001;Uriu et al, 2017). The occurrence of the flowering, fruiting and foliage exchange stages may directly or indirectly impact assemblages in canopies, as well as that observed for other arthropod groups in the Pantanal (Battirola et al, 2009;Marques et al, 2006Marques et al, , 2014Meurer et al, 2015;Yamazaki et al, 2016).…”

“…The monodominant areas correspond to seasonally flooded forests with predominance of Vochysia divergens Pohl. (Vochysiaceae), regionally known as cambará, a tree species considered invasive to the Pantanal's natural fields (Pott & Pott, 1994;Arieira & Nunes-da-Cunha, 2006;Signor et al, 2010;Uriu et al, 2017). This kind of forest is 5-19 m high and it is common to find other tree species such as Calophyllum brasiliense Cambess.…”

Phytochemical variation among populations of Fouquieria splendens Engelm. (Fouquieriaceae)

“…There is an interest in understanding how secondary metabolites allow plant species and populations to adapt to changing environmental conditions (Sundqvist et al 2012), which may be crucial for determining distribution patterns of phytochemicals in plants (Darrow & Bowers 1997). Knowledge of abundance, diversity, and distribution of secondary compounds, like phenolics, is essential for the understanding of the ecological interactions, contributing to a better comprehension of the functioning of ecosystems (Uriu et al 2017), for instance, how chemical diversity within populations helps to prevent herbivores from developing resistance to defense compounds (Laitinen et al 2000).…”

Reproductive Phenology of Macrophyte Community in Response to Wetland Flooding Cycle

“…In the second year, the flood cycle was temporally normal, emergent species flowered in the phase with the lowest water level, though without correlation, we observed in the field this phenological "behaviour" of emitting flowers at the end of receding, in shallower depths. Besides morphological and physiological adaptations, the plants present phenological strategies, allowing the synchronization of the reproductive phenophases, seed dispersal and leaf change under different seasonal conditions (Uriu et al 2017), what can explain such investment of the emergent species in phases when the shortage of resources begins.…”

“…The phenological reaction in response to environmental stressing factors (Schat & Van Beckhoven 1991, Haugaasen & Peres 2005 is easily evidenced in wetlands under seasonal floods (Junk & Piedade 1997, Thomaz et al 2007. In the Pantanal, the water regime strongly influences the phenology of the vegetation (Grace 1989, Maia & Piedade 2000, Nunes-da-Cunha & Junk 2001, Bertazzoni & Damasceno-Júnior 2011, Fava et al 2011, Marestoni 2011, Catian et al 2017, Uriu et al 2017, organizing mainly the macrophyte community by function of seasonal flood (Prado et al 1994, Gratani 2014, Ortega et al 2015, Catian et al 2018.…”