Physiological effects of ultraviolet radiation on invasive Grateloupia turuturu

Invasive species are organisms that enter an ecosystem as a result of anthropological activities. These species compete with native species in the environment where they settle, threatening the ecological structure and changing biodiversity. Grateloupia turuturu, known as an invasive species, was reported for the first time in May 2015 from the coast of Bandırma in Turkey and it was determined that it is now distributed in Erdek and Mudanya coasts. In general, invasive species are known to have a wide tolerance to ecological variables. Therefore, the aim of this study was to determine the physiological effects of UVR on G. turuturu species and to investigate the responses of G. turuturu species to UVR. For this purpose, G. turuturu samples were cultured in 3 different light regimes (photosynthetically active radiation, UVA and UVB) and their physiological responses were investigated. The data obtained showed that the photosynthetic activity and nitrate reductase enzyme activities of the samples exposed to UVR increased, whereas the accessory pigment content did not change. In conclusion, G. turuturu is able to utilize UVA energy as light sources in photosynthesis and is tolerant but not sensitive to UVR. Therefore, it is thought that G. turuturu may be advantageous in competition with local species.