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The lethal and sublethal effects of the seed oils of two indigenous plants of the Algerian Sahara, Peganum harmala L. (Zygophyllaceae) and Datura stramonium L. (Solanaceae), were investigated. Administration of 60 μl of oil by forced oral injection using a micropipette to the L5 larvae of Schistocerca gregaria Forsk. (Orthoptera: Acrididae) revealed the deterrent effect of these oils on treated larvae. The treatment resulted in various toxicological symptoms, such as intense defecation, diarrhea, weight loss, reduction in motor activity, delay and difficulty in molting and, in the most extreme cases, the death of treated individuals. During the treatment of L5 larvae of S. gregaria with P. harmala seed oil, various toxicological symptoms appeared: 81.81% of individuals presented with diarrhea; 68.18% of individuals lost weight; 72.72% exhibited reduced motor activity, and 100% of surviving individuals experienced a delay in their molt. On the other hand, in L5 larvae treated with D. stramonium seed oil, 77.27% of individuals had diarrhea, 100% showed weight loss and 100% of individuals reduced their motor activity. D. stramonium seed oil has been shown to be more toxic than P. harmala seed oil. The oral administration of 60 μl of D. stramonium seed oil caused the blocking of the phenomenon of exuviation in 100% of the treated L5 larvae, resulting in death after 16 days. While P. harmala seed oils caused 50% mortality after 12 days, the 50% surviving individuals were able to complete their imaginal molt with difficulties, which resulted in malformations. The estimated lethal time 50 (LT50) in larvae (L5) treated with D. stramonium seed oil was 3.67 days. It was more toxic than the LT50 obtained in larvae (L5) treated with the oil of P. harmala seeds, which was 12 days. The food intake in L5 larvae of S. gregaria treated with D. stramonium seed oil was 0.28 ± 0.18 g/day, it was lower than the average daily consumption recorded in the L5 larvae treated with P. harmala

The lethal and sublethal effects of the seed oils of two indigenous plants of the Algerian Sahara, Peganum harmala L. (Zygophyllaceae) and Datura stramonium L. (Solanaceae), were investigated. Administration of 60 μl of oil by forced oral injection using a micropipette to the L5 larvae of Schistocerca gregaria Forsk. (Orthoptera: Acrididae) revealed the deterrent effect of these oils on treated larvae. The treatment resulted in various toxicological symptoms, such as intense defecation, diarrhea, weight loss, reduction in motor activity, delay and difficulty in molting and, in the most extreme cases, the death of treated individuals. During the treatment of L5 larvae of S. gregaria with P. harmala seed oil, various toxicological symptoms appeared: 81.81% of individuals presented with diarrhea; 68.18% of individuals lost weight; 72.72% exhibited reduced motor activity, and 100% of surviving individuals experienced a delay in their molt. On the other hand, in L5 larvae treated with D. stramonium seed oil, 77.27% of individuals had diarrhea, 100% showed weight loss and 100% of individuals reduced their motor activity. D. stramonium seed oil has been shown to be more toxic than P. harmala seed oil. The oral administration of 60 μl of D. stramonium seed oil caused the blocking of the phenomenon of exuviation in 100% of the treated L5 larvae, resulting in death after 16 days. While P. harmala seed oils caused 50% mortality after 12 days, the 50% surviving individuals were able to complete their imaginal molt with difficulties, which resulted in malformations. The estimated lethal time 50 (LT50) in larvae (L5) treated with D. stramonium seed oil was 3.67 days. It was more toxic than the LT50 obtained in larvae (L5) treated with the oil of P. harmala seeds, which was 12 days. The food intake in L5 larvae of S. gregaria treated with D. stramonium seed oil was 0.28 ± 0.18 g/day, it was lower than the average daily consumption recorded in the L5 larvae treated with P. harmala

This study examines the inventory of the arthropodological fauna of two humid zones in the Ouargla cuvette (Northern Sahara Algerian East) which are Hassi Ben Abdallah lake and the Sebkhet Sefioune lake. For a systematic inventory of species, different techniques are used. This inventory reveals a fauna which is rich of 151 species. These species are divided into 85 families, 11 orders and 3 classes (Ostrachoda, Arachnida and Insecta). The Insecta class is better represented with 9 orders grouping 74 families. It is followed by that of the Arachnida with 1 order counting 10 families. The Ostrachoda are the least represented with 1 order and one family. At the lake of Hassi Ben Abdallah, 90 species of arthropods are inventoried. They are distributed among 63 families. For Sebkhet Sefioune Lake and during the period from July 2014 to June 2015, 101 species are listed, spread over 59 families. It is noted that 39 species listed in 35 families are common to both lakes in Ouargla cuvette. However, 50 species are found only at Hassi Ben Abdallah Lake with 22 families, While 61 species are grouped into 19 families which are captured only at Sebkhat Sefioune Lake. This station has more species, but fewer families. However, it should be noted that the order Odonatoptera is absent at this lake. The proliferation in these two humid zones of an arthropodological fauna is better suited to the hypothesis of an improvement in trophic resources than to a direct action of climatic factors. Keywords: humid zones, Ouargla, Hassi Ben Abdallah lake, Sebkhet Sefioune lake, arthropods, arid zone.

This study examines the inventory of the arthropodological fauna of two humid zones in the Ouargla cuvette (Northern Sahara Algerian East) which are Hassi Ben Abdallah lake and the Sebkhet Sefioune lake. For a systematic inventory of species, different techniques are used. This inventory reveals a fauna which is rich of 151 species. These species are divided into 85 families, 11 orders and 3 classes (Ostrachoda, Arachnida and Insecta). The Insecta class is better represented with 9 orders grouping 74 families. It is followed by that of the Arachnida with 1 order counting 10 families. The Ostrachoda are the least represented with 1 order and one family. At the lake of Hassi Ben Abdallah, 90 species of arthropods are inventoried. They are distributed among 63 families. For Sebkhet Sefioune Lake and during the period from July 2014 to June 2015, 101 species are listed, spread over 59 families. It is noted that 39 species listed in 35 families are common to both lakes in Ouargla cuvette. However, 50 species are found only at Hassi Ben Abdallah Lake with 22 families, While 61 species are grouped into 19 families which are captured only at Sebkhat Sefioune Lake. This station has more species, but fewer families. However, it should be noted that the order Odonatoptera is absent at this lake. The proliferation in these two humid zones of an arthropodological fauna is better suited to the hypothesis of an improvement in trophic resources than to a direct action of climatic factors. Keywords: humid zones, Ouargla, Hassi Ben Abdallah lake, Sebkhet Sefioune lake, arthropods, arid zone.

In order to identify the diversity and the characterization of a group of predatory insects which is Mantodea, a special study of this group took place in a dryland habitat which is Ghardaïa (Algerian septentrional Sahara). Catches come from several sampling sites corresponding to several habitats (Reg, Wadi and palm grove). Twelve species belonging to five families are inventoried of which 2 species are endemic; Eremiaphila mzabi and Eremiaphila moreti not yet reported in Algeria.The palm grove accommodate the largest species richness (S = 9 species). Mantidae is the richest family (S = 4). The palm grove has a diversity index H' going from 1.42 bit to 1.66 bit and equitability E varies between 0.73 and 0.75. A gradient of vegetation cover reveals stratification in three habitats: palm grove, river and Reg. This heterogeneity of landscapes seems to influence Mantids diversity which is proportional to the vegetation cover, except for the genre Eremiaphila. Mantids identified in these habitats can be classified in three groups, a first group strictly related to palm grove, a second subservient to the natural habitat Reg and a third group with no net belonging, being simultaneously present in both habitats. An inter-habitat variability is emphasized and strata preferences can be distinguished for each species of. The feeding activity of Mantodea is estimated by analyzing their faeces. The diet of mantis confirms their strong entomophagy. For Sphodromantis viridis, the diet is composed of 42.7% of Hymenoptera followed by 19.7% of Aranea (H = 1.68 bit, L = 0.22; E = 0.38). For Amblythespis granulata, analysis of the content of feces reveals 37.7% of Orthoptera (H = 1.58 bits, Simpson’ index = 0.20 and equitability = 0.42). This potentially gives them an impact on populations of prey species.

In order to identify the diversity and the characterization of a group of predatory insects which is Mantodea, a special study of this group took place in a dryland habitat which is Ghardaïa (Algerian septentrional Sahara). Catches come from several sampling sites corresponding to several habitats (Reg, Wadi and palm grove). Twelve species belonging to five families are inventoried of which 2 species are endemic; Eremiaphila mzabi and Eremiaphila moreti not yet reported in Algeria.The palm grove accommodate the largest species richness (S = 9 species). Mantidae is the richest family (S = 4). The palm grove has a diversity index H' going from 1.42 bit to 1.66 bit and equitability E varies between 0.73 and 0.75. A gradient of vegetation cover reveals stratification in three habitats: palm grove, river and Reg. This heterogeneity of landscapes seems to influence Mantids diversity which is proportional to the vegetation cover, except for the genre Eremiaphila. Mantids identified in these habitats can be classified in three groups, a first group strictly related to palm grove, a second subservient to the natural habitat Reg and a third group with no net belonging, being simultaneously present in both habitats. An inter-habitat variability is emphasized and strata preferences can be distinguished for each species of. The feeding activity of Mantodea is estimated by analyzing their faeces. The diet of mantis confirms their strong entomophagy. For Sphodromantis viridis, the diet is composed of 42.7% of Hymenoptera followed by 19.7% of Aranea (H = 1.68 bit, L = 0.22; E = 0.38). For Amblythespis granulata, analysis of the content of feces reveals 37.7% of Orthoptera (H = 1.58 bits, Simpson’ index = 0.20 and equitability = 0.42). This potentially gives them an impact on populations of prey species.

The date, fruit of the date palm, constitute the staple food of Saharan people. The study of its composition enables not only its valuation, but also offers it the possibility of being used as raw material in various bioproducts eleboration. The objective sought through this study aims to the chemical characterization and evaluation of the antioxidant activity of three varieties of dates : Ghars (date with soft consistency), Deglet-Nour (date with semi-dry consistency) and Degla-Beida (date with dry consistency) of Ouargla oasis harvesting at "Tmar" stage (full maturity). Sugars were identified by thin layer chromatography, the minerals were analyzed by atomic absorption spectrophotometer, the cellulose by Weende’s method, pectins by calcium pectate. The phenolic compounds were measured using Folin-Ciocalteu method, the flavonoids by aluminum trichloride method of and the condensed tannins by the butanol-HCl method. The antioxidant activity was measured by the inhibition test of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical. The results showed that the three varieties of dates are rich in iron, magnesium and potassium and constitute a significant source of calcium. The variety Deglet-Nour is the richest in phenolic compounds with 14.23±0.73 mg of gallic acid equivalents/100 g of dates. The flavonoids content ranges between 0.20±0.05 and 2.39±0.08 mg of rutin equivalents/100 g of dates, the the condensed tannins varies between 0.008±0.00 and 0.06±0.08 mg of tannic acid equivalents/100 g of dates. The ethyl acetate extract of the variety of date Ghars has a high antioxidant activity with an EC50 of 5.72 mg/ml. These results show that the dates of Saharan region of Ouargla can be a good source of natural antioxidants and minerals.

In order to identify the diversity and the characterization of a group of predatory insects which is Mantodea, a special study of this group took place in a dryland habitat which is Ghardaïa (Algerian septentrional Sahara). Catches come from several sampling sites corresponding to several habitats (Reg, Wadi and palm grove). Twelve species belonging to five families are inventoried of which 2 species are endemic; Eremiaphila mzabi and Eremiaphila moreti not yet reported in Algeria.The palm grove accommodate the largest species richness (S = 9 species). Mantidae is the richest family (S = 4). The palm grove has a diversity index H' going from 1.42 bit to 1.66 bit and equitability E varies between 0.73 and 0.75. A gradient of vegetation cover reveals stratification in three habitats: palm grove, river and Reg. This heterogeneity of landscapes seems to influence Mantids diversity which is proportional to the vegetation cover, except for the genre Eremiaphila. Mantids identified in these habitats can be classified in three groups, a first group strictly related to palm grove, a second subservient to the natural habitat Reg and a third group with no net belonging, being simultaneously present in both habitats. An inter-habitat variability is emphasized and strata preferences can be distinguished for each species of. The feeding activity of Mantodea is estimated by analyzing their faeces. The diet of mantis confirms their strong entomophagy. For Sphodromantis viridis, the diet is composed of 42.7% of Hymenoptera followed by 19.7% of Aranea (H = 1.68 bit, L = 0.22; E = 0.38). For Amblythespis granulata, analysis of the content of feces reveals 37.7% of Orthoptera (H = 1.58 bits, Simpson’ index = 0.20 and equitability = 0.42). This potentially gives them an impact on populations of prey species.

The date, fruit of the date palm, constitute the staple food of Saharan people. The study of its composition enables not only its valuation, but also offers it the possibility of being used as raw material in various bioproducts eleboration. The objective sought through this study aims to the chemical characterization and evaluation of the antioxidant activity of three varieties of dates : Ghars (date with soft consistency), Deglet-Nour (date with semi-dry consistency) and Degla-Beida (date with dry consistency) of Ouargla oasis harvesting at "Tmar" stage (full maturity). Sugars were identified by thin layer chromatography, the minerals were analyzed by atomic absorption spectrophotometer, the cellulose by Weende’s method, pectins by calcium pectate. The phenolic compounds were measured using Folin-Ciocalteu method, the flavonoids by aluminum trichloride method of and the condensed tannins by the butanol-HCl method. The antioxidant activity was measured by the inhibition test of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical. The results showed that the three varieties of dates are rich in iron, magnesium and potassium and constitute a significant source of calcium. The variety Deglet-Nour is the richest in phenolic compounds with 14.23±0.73 mg of gallic acid equivalents/100 g of dates. The flavonoids content ranges between 0.20±0.05 and 2.39±0.08 mg of rutin equivalents/100 g of dates, the the condensed tannins varies between 0.008±0.00 and 0.06±0.08 mg of tannic acid equivalents/100 g of dates. The ethyl acetate extract of the variety of date Ghars has a high antioxidant activity with an EC50 of 5.72 mg/ml. These results show that the dates of Saharan region of Ouargla can be a good source of natural antioxidants and minerals.