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El Harrach, Algeria

Mimeche F.,University Of Msila | Biche M.,National Agronomic Institute
AACL Bioflux | Year: 2015

Length-weight (L-W) relationships for 4 non-native cyprinid species collected in the Ain Zada reservoir (North-East of Algeria): Cyprinus carpio (Linnaeus, 1758), Hypophtalmichthys molitrix (Valenciennes, 1844), Hypophtalmichthys nobilis (Richardson, 1845) and Carassius auratus gibelio (Bloch, 1782). The values of the exponent b are in the L-W relationships ranged from 2.43 to 3.37. This is the first L-W parameters reported for four non-native freshwater fish in Algeria. © 2015 BIOFLUX SRL. All rights reserved. Source


Jebari S.,National Research Institute for Rural Engineering | Jebari S.,Lund University | Berndtsson R.,Lund University | Lebdi F.,National Agronomic Institute | Bahri A.,African Development Bank
Hydrological Sciences Journal | Year: 2012

Agricultural use and related water erosion may lead to significant changes in the sedimentological and hydrological characteristics of watersheds, and therefore negative consequences for rural development. This research aimed to put present-day soil erosion of the important Mejerda catchment into a historical context. The catchment of Wadi Mejerda in northern Tunisia has experienced soil erosion due to weather and human impacts for thousands of years. We used historical texts and results from archaeological research that go back to 1000 BC, as well as data collected during the last century. Soil erosion from different types of agricultural landscape management was analysed together with information on the soils' production potential, the hydrographic network and flood frequency. The results showed that water erosion has increased the hydrographic network by 65 km and increased the deltaic plain by as much as 15 km2/century. However, soil productivity has decreased significantly. Moreover, due to in channel sedimentation and river choking, the number of flooding occurrences has multiplied over the last century. Finally, it is shown that water erosion follows a specific cycle of degradation throughout the watershed. These findings should be considered for better water and soil management in the context of semi-arid areas. © 2012 Copyright 2012 IAHS Press. Source


Morsi A.,National Agronomic Institute | Mimeche F.,University Of Msila | Biche M.,National Agronomic Institute
AACL Bioflux | Year: 2015

The age and growth of Algerian barbel, Luciobarbus callensis (Valenciennes, 1842), in El- Harrach River (North of Algeria) were studied in samples taken from catches of local fishermen obtained between June 2013 and May 2014. The maximum length was 25.5 cm (TL - total length) in females and 23.5 cm in males. Among 1000 specimens representing 7 age classes (from 0+ to 6+), fishes of 2+ and 4+ was dominant (79.8 %). The population of L. callensis consists of 834 individuals matures (357 females and 477 males). The calculated overall sex ratio is 1:0.74 (Chi² X² = 58.59, P<0.01). Length- weight relations were calculated for females, males, immature and all specimens. Isometric growth was observed for the both sex and immature with slopes (b values) of the length-weight relationships ranged from 3.021±0.027 (males) to 3.070±0.055 (immature). The Von Bertalanffy equation for the theoretical growth in length was: Lt = 26.249[1-e-0.23(t-0.281)] for males and Lt = 23.158[1-e-0.31(t-0.213)] for females. © 2015, BIOFLUX SRL. All rights resereved. Source


Ghalmi N.,National Agronomic Institute | Malice M.,University of Liege | Jacquemin J.-M.,Walloon Agricultural Research Center | Ounane S.-M.,National Agronomic Institute | And 2 more authors.
Genetic Resources and Crop Evolution | Year: 2010

Twenty landraces of cowpea (Vigna unguiculata (L.) Walp.) scattered throughout Algeria were compared through morphological and genetic characterization. At the morphological level, for qualitative characters there was no intra-landrace variation and for quantitative characters the variations were low except for landrace NAG2 Three different cultigroups were located in Algeria: Biflora that was dominant in the Sahara, Melanophtalmus in the North and Unguiculata including one landrace in Kabylia and two in Sahara. The AMOVA analysis indicated that the genetic variation was lower within than among agro-ecological regions. A Mantel test, revealed a correlation between the qualitative morphological data and the geographical data (R = 0.28; P < 0.01), indicating that the degree of morphological change among landraces was roughly proportional to the geographical distances separating them. Genetic diversity was analyzed by using 11 random amplified polymorphic DNA (RAPD) and 12 inter-simple sequence repeat (ISSR) markers. No intra-landrace variability was found. The eleven RAPD primers yielded 77 bands, of which 45 (58.44%) were polymorphic; the genetic similarity ranged from 66.0 to 96.7%. The twelve ISSR primers provided a total of 104 bands, of which 65 (62.5%) were polymorphic; the genetic similarity ranged from 62.8 to 97.8%. cluster analysis showed a good match between genetic background and geographical distribution, which was confirmed by the results of the Mantel test. In particular, geographical data and genetic data were found to be correlated: (R = 0.33; P < 0.01) for RAPD, (R = 0.37; P < 0.01) for ISSR, and (R = 0.33; P < 0.01) for a combined RAPD-ISSR dataset. Moreover, despite the absence of significant correlation between morphological and RAPD data (R = 0.14; P = 0.14), significant correlations between morphological data and both ISSR (R = 0.27, P < 0.05) and a combined RAPD-ISSR dataset (R = 0.22, P < 0.05) were noted. ISSR markers were better linked to morphological variation than were RAPD markers. However, despite this, genetic distances among these landraces were found to be essentially the same no matter which markers were used. © Springer Science+Business Media B.V. 2009. Source


Nouani A.,University of Boumerdes | Nouani A.,National Agronomic Institute | Moulti-Mati F.,Mouloud Mammeri University | Belbraouet S.,University of Moncton | Bellal M.M.,National Agronomic Institute
African Journal of Biotechnology | Year: 2011

Crude enzymatic extract obtained from five fermentations (300 g of wheat bran) was characterized by a clotting activity of 0.34 ± 0.08 UP/ml with a strength ratio of 1/1: 200. The comparative study of the summaries from 2 purification protocols showed that it is possible to recover 6% of the initial proteins with a 44.54% activity after gel filtration (protocol I), which appeared more technically sound when compared to ion-exchange (1.80% of total proteins with a 23% performance) (protocol II). The protein homogeneity (a single electrophoretic band) of the monomeric protease was confirmed by both methods after precipitation with 80% saturated ammonium sulphate. Moreover, the fractional precipitation technique with this salt (40 and 80%) was useless in the experimental conditions employed and an important loss of activity was observed (28.53%) with a 3-fold purification. In another part of the study, without ammonium sulphate precipitation, the gel filtration enabled the elimination of almost 97% of the inactive proteins and improved the activity performance by 55.13%, while multiplying the specific activity of the coagulant by a factor of 20.88 against a 6.75-fold purification with ionexchange and the appearance of a more or less 20 kDa peptide after electrophoresis. The proteolytic activity of the purified extracts had a similar appearance to a more pronounced kinetic when compared with the reference rennet. The purification protocols did not seem to have an impact on the isolated protease activity. © 2011 Academic Journals. Source

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