الفهرس 
Tested alga:Only 14 pages are availabe for public view
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Abstract
Growth of the green alga Dunaliella parva was studied and optimized under some factors such as different light intensities(250 ~ 700 μ mol m-2 s-1) and qualities (blue- green- red) beside the control (400 μ mol m-2 s-1 and white light).Effect of different salinity levels of NaCl (0.5, 1, 2, 2.5 and 3.5 M) beside the control (1.25 M NaCl) was also studied, the growth was monitored by cell number, pigment content((Chl a),(Chl b) and carotenoids).The optimal growth and the highest the photosynthetic efficiency FV / Fm) were recorded at light intensity of 400 μ mol m-2 s-1, white light and 1.25 M NaCl. Activity of antioxidant enzymes (catalase, peroxidase, ascorbic acid oxidase) and ascorbate content were determined and varied according to the growth conditions. The grown alga under the optimal conditions was exposed to different stresses (nitrogen, phosphorus starvation, salinity and (MnCl2) either singly or combined. Then protein, carbohydrate and glycerol contents were determined in algal cells. Under nitrogen and phosphorus starvation either singly or combined, the growth rate and the metabolic activities were decreased. Under salt stress(2.5 M NaCl) combined with N starvation and heavy metals stress, glycerol production increased, while synthesis of glycerol decreased under salt stress of 1 M NaCl and P starvation