Allelopathic inhibitory effect of the macroalga Pyropia haitanensis (Rhodophyta) on harmful bloom-forming Pseudo-nitzschia species. (December 2020)

• Record Type: Journal Article
• Authors: Patil, Vishal; Abate, Rediat; Wu, Weiwei; Zhang, Jiawei; Lin, Huina; Chen, Changping; Liang, Junrong; Sun, Lin; Li, Xuesong; Li, Yang; Gao, Yahui
• Is Part Of: Marine pollution bulletin. Volume 161:Part A(2020)
• Publication Date: 2020-12
• Subjects: Allelopathy -- Growth inhibition -- Harmful algal bloom (HAB) -- Pseudo-nitzschia -- Pyropia haitanensis; Marine pollution -- Periodicals; Marine Biology -- Periodicals; Water Pollution -- Periodicals; Mer -- Pollution -- Périodiques; Publications périodiques; Pollution des mers; Lutte antipollution; Electronic journals; 363.7394
• DOI: 10.1016/j.marpolbul.2020.111752
• Languages: English
• ISSNs: 0025-326X

Abstract

Abstract: The blooms of harmful microalgae represent a prominent threat to fisheries, public health, and economies throughout the world. Recent studies have shown that certain macroalgae release allelochemicals that can inhibit the growth of bloom-forming microalgae. In this study, we found that the macroalga Pyropia haitanensis significantly inhibited growth of the harmful bloom-forming microalgae Pseudo-nitzschia pungens and Pseudo-nitzschia multiseries . The inhibitory-effect of the live thali of P. haitanensis was highest, followed by that of dry powder, water-soluble extract, and culture medium filtrate. The Pseudo-nitzschia species died 96 h after exposure to 5–10 g fresh-weight L −1 of P. haitanensis live thalli. Furthermore, an aqueous extract of P. haitanensis suppressed the growth of P. pungens and P. multiseries, thereby indicating that P. haitanensis contains stable allelopathic substances that cause the observed inhibitory-effects. On the basis of these findings, we conclude that the macroalga P. haitanensis would have potential utility in controlling the blooms of Pseudo-nitzschia species. Highlights: Red macroalga Pyropia haitanensis inhibits the bloom-forming and toxic Pseudo-nitzschia species. Supplementation of P. haitanensis at 5 and 10 g FW L −1 completely inhibits the Pseudo-nitzschia species. Various treatments confirm that P. haitanensis releases stable allelochemicals which inhibits Pseudo-nitzschia sp. Inhibition potency of P. haitanensis varies with the cell densities of the microalgae.