The occurrence of bleaching stripe disease inGracilaria corticataand controlling of the disease using quorum quenching approach

Abstract

In the present study, the Gram-negative bacteria Vibrio and Pseudoalteromonas species associated with Gracilaria corticata found to be opportunistic pathogens that caused bleaching stripe disease on its host. Consortium of these pathogens induced maximum disease symptoms with 27.3 mm long bleaching stripe. Presence of Gram-positive bacteria Bacillus reduced the disease appearances in the co-culture of Gram-negative bacteria. Each Gram-negative bacteria had capability to produce two different types of AHLs. For the first time found that in the addition of (Z-) - 4- Bromo- 5- (bromomethylene) - 2(5H)- furanone with co-culture of pathogenic bacteria and host fronds significantly minimized the bleaching stripe symptoms. Incubating of pathogenic bacteria with 8 and 10 μm ml(-1) of furanone did not able to induce disease symptoms. The present study will help to understand the chemical interaction between Gram- positive and negative bacteria in marine environment. This article is protected by copyright. All rights reserved.