Ünal D.Işik N.O.Sukatar A.2019-10-262019-10-2620101300-01521300-0152https://doi.org/10.3906/biy-0810-3https://hdl.handle.net/11454/19896In order to contribute to the understanding of its response to metal stress, Ulva lactuca (L.) was treated with different concentration of chromium (VI) (0.2, 0.5, 1, and 5 mM K2CrO4), and alterations in Fv/Fm ratio (maximal photochemical efficiency of PSII) and cell viability were investigated. Significant alterations of the maximal photochemical efficiency of PSII (Fv/Fm) ratio were observed in response to the increase in chromium concentration. The Fv/Fm ratio decreased in Ulva lactuca following 2 h treatment with 1 and 5 mM Cr(VI) solution. The cell viability was decreased in cells exposed to higher Cr(VI) concentrations. Thallus cell morphology was altered in thalli exposed to chromium. A cytotoxic effect of chromium was demonstrated for the first time using acridine orange/ethidium bromide staining in macroalgae. In 1 and 5 mM of Cr(VI) treated samples, the rate of necrotic cells increased about 76.93% and 84.23%, respectively. © TÜBİTAK.tr10.3906/biy-0810-3info:eu-repo/semantics/closedAccessAcridine orange/ethidium bromide stainingChromium VIPhotosynthesisUlva lactucaArticle342119124Q2