I. Moreno-garrido et Jp. Canavate, Assessing chemical compounds for controlling predator ciliates in outdoor mass cultures of the green algae Dunaliella salina, AQUACULT EN, 24(2), 2001, pp. 107-114
Effects of different chemical compounds on ciliates grazing outdoor mass cu
ltures of Dunaliella salina were studied. These taxonomically undetermined
ciliates were capable of clarifying dense algal cultures within 2 days and
tolerated a wide salinity range (up to 215 ppt). Treatments of micro-algal
cultures with either formaldehyde, ammonia, hydrogen peroxide or metronidaz
ole were inappropriate since lethal doses for the ciliate: also eliminated
algal cells, However, the use of quinine sulphate rapidly destroyed ciliate
s while keeping algal cells alive. A 24-h LC100 at 12-14 mg 1(-1) quinine s
ulphate was found for the ciliate, whereas a 72-h EC50%, at 14.5 +/- 0.6 mg
1(-1) was found Tor Dunaliella. The application of a dose of 10 mg 1(-1) q
uinine to contaminated outdoor algal mass cultures completely eliminated ci
liates within a short time, and allowed the algal population to start recov
ering. (C) 2001 Elsevier Science B.V. All rights reserved.