Physiological responses of Ankistrodesmus acicularis to diuron

Abstract

The impact of diuron on the fresh water alga Ankistrodesmus acicularis was investigated. Parameters studies were the effect on photosynthetic pigments, growth rate, ¹⁴C-photoassimilation, carbohydrate, protein, and free amino acids contents, adenosine triphosphate (ATP), uptake of nitrate and diuron by algal cells. Photosynthetic pigments [chlorophylls (a) and (b) contents and total carotenoids] of diuron—treated algae were significantly decreased compared to control. Carbohydrate, protein, and free amino acids contents of treated algae were significantly decreased in response to diuron treatments. The values of EC₅₀, which exert 50% inhibition, were calculated by Probit test which varied with respect to the exposure time. Decreased in ¹⁴C-photoassimilation and ATP were in harmony with the decrease of other determined metabolic activities.

Keywords:

• Algae
• Toxicity
• Diuron
• Herbicide
• Photosynthesis
• Uptake