The effects of phosphate on physiological responses and carbohydrate production in Ulva fasciata (Chlorophyta) from upwelling and non-upwelling sites

• DOI: 10.1515/bot-2020-0051
• Publication Date: 2021-01-15T00:27:36Z
• Authors: Tiphane Andrade F...; Nuno Tavares Martins; Lígia Ayres-Ostrock; Estela M. Plastino; Alex Enrich-Prast; Vinícius Peruzzi ...
• Keywords: 2. Zero hunger; 0106 biological sciences; 01 natural sciences

Abstract Phosphorus is a key macronutrient in macroalgal physiology, including carbohydrate anabolism. To determine the effects of phosphorus on different physiological parameters, we cultivated Ulva fasciata specimens from distinct localities (upwelling and non-upwelling sites) presence phosphate concentrations (0, 2, 4 µM <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <m:mrow> <m:msubsup> <m:mtext>PO</m:mtext> <m:mn>4</m:mn> <m:mn>3</m:mn> <m:mo>−</m:mo> </m:mrow> </m:msubsup> </m:math> ${\text{PO}}_{4}^{3-}$ ). After 15 days, growth rates were similar (approx. 12% day −1 ) contents had increased individuals both sites. In upwelling site, high all treatments (71% dry mass), whereas site under highest concentration showed lowest content (46% DM). Nevertheless, observed higher uptake concentration, indicating stress response to elevated nutrient concentrations. Individuals sites with maintained healthy photosystems over experimental period ( F v / m = 0.788), those absence evidence photosystem impairment, as indicated by progressive decline maximum quantum yield. Altogether, our results indicate that origin influence U. broad environmental variation, such events, can show productivity.