Mitchell, C. A., 1987, Growth of Halodule wrightii in culture and the effects of cropping, light, salinity and atrazine: Aquatic Botany, v. 28, no. 1, p. 25-37. Abstract: The interaction of three environmental variables, light, salinity and cropping, with the effects of the herbicide atrazine on Halodule wrightii Ascherson was investigated in the laboratory. Atrazine at 30 ppm caused a significant reduction in survival or ramets, production of new ramets, above-ground biomass and growth, when compared to H. wrightii not exposed to atrazine. The three levels of each environmental condition did not alter the toxicity of atrazine to H. wrightii . Keywords: plant-culture, sea-grass, light-effects, salinity-effects, herbicides, toxicity-tests, Halodule-wrightii, cropping