Effects of high temperature and nitrogen availability on the growth and composition of the marine diatom Chaetoceros pseudocurvisetus. (6th April 2022)

• Record Type: Journal Article
• Authors: Flanjak, Lana; Vrana, Ivna; Cvitešić Kušan, Ana; Godrijan, Jelena; Novak, Tihana; Penezić, Abra; Gašparović, Blaženka
• Editors: Foyer, Christine
• Is Part Of: Journal of experimental botany. Volume 73:Number 12(2022)
• Page Start: 4250
• Page End: 4265
• Publication Date: 2022-04-06
• Subjects: Biochemical response -- Chaetoceros pseudocurvisetus -- diatom -- global warming -- lipid remodelling -- nitrogen stress -- physiological response; Botany -- Periodicals; Botany, Experimental -- Periodicals; Plant physiology -- Periodicals; 580
• DOI: 10.1093/jxb/erac145
• Languages: English
• ISSNs: 0022-0957

Abstract

Abstract: The assimilation of inorganic nutrients by phytoplankton strongly depends on environmental conditions such as the availability of nitrogen and temperature, especially warming. The acclimation or adaptation of different species to such changes remains poorly understood. Here, we used a multimethod approach to study the viability and physiological and biochemical responses of the marine diatom Chaetoceros pseudocurvisetus to different temperatures (15, 25, and 30 °C) and different N:P ratios. Nitrogen limitation had a greater effect than high temperature on cell growth and reproduction, leading to a marked elongation of setae, decreased phosphorus assimilation, increased lipid accumulation, and decreased protein synthesis. The elongation of setae observed under these conditions may serve to increase the surface area available for the uptake of inorganic and/or organic nitrogen. In contrast, high temperatures (30 °C) had a stronger effect than nitrogen deficiency on cell death, nitrogen assimilation, chlorophyll a accumulation, the cessation of setae formation, and cell lipid remodelling. Significant changes in thylakoid lipids were observed in cells maintained at 30 °C, with increased levels of digalactosyldiacylglycerol and sulfoquinovosyldiacylglycerol. These changes may be explained by the role of galactolipids in thylakoid membrane stabilization during heat stress. Abstract : Environmental stresses such as increasing temperature and nitrogen deficiency affect different cell, physiological and biochemical processes of the marine diatom Chaetoceros pseudocurvisetus, as well as having synergistic effects.