Combined Effects of Temperature and Nutrient Availability on Growth and Phlorotannin Concentration of the Brown Alga <i>Sargassum patens</i>(Fucales;Phaeophyceae)

作     者：Hikaru Endo Kentaro Suehiro Junji Kinoshita Xu Gao Yukio Agatsuma 

作者机构：Graduate School of Agricultural Science Tohoku University Sendai Ja-pan 

出 版 物：《American Journal of Plant Sciences》 (美国植物学期刊（英文）)

年 卷 期：2013年第4卷第12期

页      面：14-20页

学科分类：1002[医学-临床医学] 100214[医学-肿瘤学] 10[医学] 

主　　题：Climate Change Plant-Animal Interaction Anti-Herbivore Defense Secondary Metabolite Habitat-Forming Macroalga 

摘      要：Global warming is predicted to affect plant-herbivore interactions. However, little is known about the effects of temperature on marine plant secondary chemistry and how these effects may impact plant-herbivore interactions. As marine macroalgae can become physiologically stressed due to warm water temperatures and nutrient-poor conditions during summer, we conducted a culture experiment to test the combined effects of temperature (10°C, 20°C, 30°C) and nutrient availability (seawater enriched with 25% PESI medium and non-enriched seawater) on relative growth rate (RGR) and concentration of phlorotannins (i.e., defensive compounds) in the upper and lower parts of shoots of the brown alga Sargassum patens. RGR was affected by temperature but not by nutrient availability. Phlorotannnin concentration was affected by nutrient availability but not by temperature, although there was a significant interaction between temperature and part of the shoots. Correlations between RGR and phlorotannin concentration were significant for the upper part of the shoots but not for the lower part. These correlations were slightly positive in the nutrient-enriched medium but negative in the non-enriched medium. These results suggest that temperature affects phlorotannin concentration of S. patens indirectly via changes in the growth rate and that its effect depends on the part of the shoot and nutrient availability.