Effects of Diuron, Terbuthylazine and Isoproturon on Photochemical and Non-Photochemical Quenching of Ectocarpus siliculosus

• Published in: IOP Conference Series: Earth and Environmental Science
• Main Author: Hashim M.A.; Kamaruddin S.A.; Yam M.F.; Khazali A.S.; Kamil K.A.; Nasir N.A.H.A.; Brown M.T.
• Format: Conference paper
• Language: English
• Published: Institute of Physics 2022
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85130239943&doi=10.1088%2f1755-1315%2f1019%2f1%2f012015&partnerID=40&md5=ff8250f8221cd51491412f38a92ef90e

The influence of anthropogenic discharges on the environment is an increasing concern among environmental toxicologists. This investigation set out to analyse the impacts of selected herbicides; diuron, terbuthylazine and isoproturon on two strains of Ectocarpus siliculosus with different pollution histories, LIA4 and Es524. Evaluation of their effects on photochemical quenching (qP) and non-photochemical quenching (qN) indicators have demonstrated negative impacts of all herbicides on both strains. From the results, diuron shows to exert significant negative effect at concentration as low as 5 μg L-1 followed by terbuthylazine at 10 μg L-1 (qP) and 5 μg L-1 (qN), and isoproturon at 100 μg L-1 (qP) and 50 μg L-1 (qN). Non-photochemical quenching (qN) indicator was found to exhibit greater sensitivity to the herbicides compared to photochemical quenching (qP). In both strains of E. siliculosus, the three herbicides were ranked in order of toxicity: diuron > terbuthylazine > isoproturon. This investigation provides new information on ecotoxicology of herbicides towards brown algae. © Published under licence by IOP Publishing Ltd.