This study aimed to test the effectiveness of physical and chemical procedures for surface decontamination of Bostrychia binderi Harvey. For this, thalli were washed and immersed in chemical solutions (5% liquid detergent, 1% povidone iodine and 0.2% sodium hypochlorite) at different times and combinations. After treatments the thalli were cultivated in laboratory to verify possible negative effects caused by the procedures to alga. Contaminating organisms in the algal culture medium were quantified at the end of cultivation. Washing, spraying, removing of macrofauna individuals with tweezers, thalli immersion in 5% liquid detergent for 60 seconds, after in 0.2% sodium hypochlorite for 2 minutes were effective procedures to eliminate all contaminants analyzed. Thalli immersion in 1% povidone iodine did not affect negatively the thalli growth, whereas immersion in 0.2% sodium hypochlorite for 5 minutes affected. For establishment of Bostrychia’s unialgal cultures we recommend the proposed protocol in this study.

Este estudo objetivou testar a eficácia de procedimentos físicos e químicos para descontaminação da superfície de Bostrychia binderi Harvey. Para isto, talos foram lavados e imersos em soluções químicas (detergente líquido 5%, iodopovidona 1% e hipoclorito de sódio 0,2%) em diferentes tempos e combinações. Após os tratamentos, os talos foram cultivados para verificar possíveis efeitos negativos causados ​​pelos procedimentos à alga. Contaminantes no meio de cultura dos talos foram quantificados no final do cultivo. Procedimentos de lavagem, remoção física de indivíduos da macrofauna, imersão de talos em detergente líquido 5% por 60 segundos, depois em hipoclorito de sódio 0,2% por 2 minutos, foram eficazes para eliminar os contaminantes analisados. Imersão de talos em iodopovidona 1% não afetou o crescimento dos talos, enquanto que imersão em hipoclorito de sódio 0,2% por 5 minutos afetou. Para estabelecimento de culturas unialgais de Bostrychia recomendamos o protocolo proposto neste estudo.

RESUMO Este estudo objetivou testar a eficácia de procedimentos físicos e químicos para descontaminação da superfície de Bostrychia binderi Harvey. Para isto, talos foram lavados e imersos em soluções químicas (detergente líquido 5%, iodopovidona 1% e hipoclorito de sódio 0,2%) em diferentes tempos e combinações. Após os tratamentos, os talos foram cultivados para verificar possíveis efeitos negativos causados pelos procedimentos à alga. Contaminantes no meio de cultura dos talos foram quantificados no final do cultivo. Procedimentos de lavagem, remoção física de indivíduos da macrofauna, imersão de talos em detergente líquido 5% por 60 segundos, depois em hipoclorito de sódio 0,2% por 2 minutos, foram eficazes para eliminar os contaminantes analisados. Imersão de talos em iodopovidona 1% não afetou o crescimento dos talos, enquanto que imersão em hipoclorito de sódio 0,2% por 5 minutos afetou. Para estabelecimento de culturas unialgais de Bostrychia recomendamos o protocolo proposto neste estudo.

ABSTRACT This study aimed to test the effectiveness of physical and chemical procedures for surface decontamination of Bostrychia binderi Harvey. For this, thalli were washed and immersed in chemical solutions (5% liquid detergent, 1% povidone iodine and 0.2% sodium hypochlorite) at different times and combinations. After treatments the thalli were cultivated in laboratory to verify possible negative effects caused by the procedures to alga. Contaminating organisms in the algal culture medium were quantified at the end of cultivation. Washing, spraying, removal of macrofauna individuals with tweezers, thalli immersion in 5% liquid detergent for 60 seconds, after in 0.2% sodium hypochlorite for 2 minutes were effective procedures to eliminate all contaminants analyzed. Thalli immersion in 1% povidone iodine did not affect negatively the thalli growth, whereas immersion in 0.2% sodium hypochlorite for 5 minutes affected. For establishment of Bostrychia unialgal cultures we recommend the protocol proposed in this study.

ABSTRACT Global change and coastal eutrophication are affecting macroalgae worldwide. We analyzed the effects of increased water temperature (25, 28 and 32 °C) and eutrophication on the growth of Bostrychia binderi and Bostrychia montagnei in a range of salinities (18, 24, 30, 36 and 42 PSU) through three independent multifactorial experiments. Both species had higher growth at 25 °C than at 28 and 32 °C (warming scenario projected by IPCC), suggesting a negative effect of ocean warming. The species showed a broad tolerance to the range of salinities tested, with higher growth at 36 and 42 PSU, as a local adaptation strategy. Oligotrophic seawater significantly affected the growth of both species because the lowest growth was found in this condition, whereas highest growth was found with increased availability of nutrients, which is probably because estuaries are nutrient-rich environments due to continental runoff. High temperatures, low salinities and few nutrients had negative interactive effects on the growth of both species. Our results show that ocean warming can be detrimental to the studied macroalgae, and that both species are tolerant to eutrophication, with B. montagnei being more sensitive than B. binderi. Our results also reinforce the euryhaline characteristic of the genus Bostrychia.