Effect of pH on growth and biochemical responses of Dunaliella bardawil and Chlorella ellipsoidea.

The goal of the present investigation was to study the effect of pH on growth and biochemical responses of Dunaliella bardawil and Chlorella ellipsoidea when exposed to different pH values. The two tested microalgae could grow in a wide range of pH (4-9 for D. bardawil and 4-10 for C.

Differential effects of thiobencarb toxicity on growth and photosynthesis of Anabaena variabilis with changes in phosphate level.

A thiobencarb dose of 3 mg L(-1) reduced the protein content of Anabaena variabilis, whereas it elevated the carbohydrate content. Measurements of Anabaena growth, photosynthetic activity, and respiration rate revealed that the high dose of phosphate (0.53 mM) exerted no additional toxic effect to thiobencarb toxicity.

Effect of pendimethalin on growth and photosynthetic activity of Protosiphon botryoides in different nutrient states.

The effect of pendimethalin on the green alga Protosiphon botryoides was investigated. Results indicate that specific growth rate, cell number, chlorophyll a level, and dry weight yield significantly decrease with increasing pendimethalin concentrations, while protein and carbohydrate contents increase significantly. On the other hand, photosynthetic activity decreases whereas dark respiration increases with high pendimethalin concentrations.

Chlorophyll a fluorescence and photosynthetic activity as tools for the evaluation of simazine toxicity to Protosiphon botryoides and Anabaena variabilis.

On studying the effect of simazine on Protosiphon botryoides and Anabaena variabilis, data revealed that chlorophyll a content and dry weight were decreased with the increase in simazine concentration. High concentration of simazine (0.8 mg L(-1)) reduced gross photosynthesis and carbohydrate content, whereas protein content and respiration rate were increased.