Category: Volume 27
Hits: 11583

Etude des peuplements piscicoles de la retenue du barrage de Sidi Salem

S. MILI^1,2*

R. ENNOURI²

H. LAOUAR³

N. BEN ROMDHANE⁴

H. MISSAOUI²

¹Unité de recherche : Exploitation des milieux aquatiques, Institut Supérieur de Pêche et d’Aquaculture de Bizerte, BP 15, 7080 Menzel Jemil, Tunisie.

²Institut National des Sciences et Technologies de la Mer, 28, rue 2 mars 1934 Salammbô, 2025, Tunis, Tunisie.

³Centre Technique d’Aquaculture, 5, rue du Sahel Montfleury, 1009 Tunis, Tunisie.

⁴Direction Générale de la Pêche et de l’Aquaculture, 30, Rue Alain Savary, 1002, Tunisie

Abstract - The study of fish populations in reservoirs is essential for sustainable management of the freshwater fisheries. The sampling technique used was based on the European standard CEN prEN 14757. This technique (multi-mesh gillnets) was adapted to Tunisian dams. A stratified random sampling was implemented according to the depth and area of the dam. Samplings were conducted in Sidi Salem reservoir between April and May 2014. The fish communities were composed by 7 species: roach, rudd, carp, pike-perch, phoxinel and two species of mullet (Liza ramada and Mugil cephalus). The weight and numeric yield was average (114 ind / 1000m² and 8.08Kg / 1000m²). The majority of catches were obtained at depths less than 12m. Populations of Mullet and carp show a strong deficit indicating a state of over-exploitation and insufficiency of stocking. Sidi Salem reservoir has a well balanced and abundant population of roach, rudd and pike-perch. However, this dam presents a remarkable deficiency of autochthon fish. Diversity indices indicate a little diversity in this dam. Additionally, we identified that the stock of mullet was declining and of eels was lack in this survey. This reservoir required a support from fisheries managers.

Keywords: Sampling, fish populations, Sidi Salem reservoir, multi-mesh gillnets.

Résumé - La gestion durable de la ressource ichtyque dans les retenues de barrages est basée sur l’étude des peuplements piscicoles qui y sont présents. La technique d’échantillonnage est inspirée de la norme européenne CEN prEN 14757. Cette méthodologie a été adoptée aux barrages tunisiens. Un échantillonnage stratifié aléatoire a été mis en œuvre selon la profondeur et la superficie du barrage de Sidi Salem. Cette retenue a été prospectée entre le mois d’avril et le mois de mai 2014. Les peuplements piscicoles inventoriés sont composés de 7 espèces : le gardon, le rotengle, la carpe commune, la phoxinelle de la calle, le sandre et les deux espèces de mulet (Mugil cephalus et Liza ramada). Les rendements enregistrés sont moyens sur le plan pondéral et numérique (8,08Kg /1000m²et 114 ind/1000m²). La majorité des captures a été obtenue à des profondeurs inférieures à 12m. Le mulet et la carpe montrent un fort déficit indiquant un état de surexploitation et une insuffisance de l’ensemencement. La retenue de Sidi Salem abrite des populations de gardon, de rotengle et de sandre bien abondantes et équilibrées. Cependant, ce barrage présente une carence remarquable en poissons autochtones. Les indices de diversité indiquent que les peuplements étudiés sont peu diversifiés au niveau du barrage de Sidi Salem. De plus, nous avons décelé un déclin du stock du mulet ainsi que l’absence de l’anguille et du silure dans le barrage prospecté. Cette retenue d’eau nécessite une intervention des gestionnaires de la pêche.

Mots clés: Echantillonnage, peuplements piscicoles, barrage Sidi Salem, filets multi-mailles.

Category: Volume 27
Hits: 7014

Diallel analysis of the resistance to powdery mildew (Erysiphe graminis f.sp. hordei ) in barley (Hordeum vulgare L.)

M. A. Bargougui

School of Higher Education in Agriculture of Mateur

Abstract - A complete diallel cross including five barley genotypes was analyzed to study the genetic interaction between barley “Hordeum vulgare” and powdery mildew “Erysiphe graminis f. sp. hordei”. The results revealed an important genetic variability. The resistance is expressed as a dominant character. The genetic decomposition of variance showed preponderant general combining ability, which let us to expect good selection efficiency. Such assumption is sustained by very high narrow sense heritability equal to 0.70. This study highlights that the varieties Manel and INAT102 as good sources of genetic resistance to barley powdery mildew. These two lines and their hybrids may be used as good head. According to the results, a genetic improvement program on the resistance to barley powdery mildew can be based on pedigree method to take advantage of the transgression within progenies.

Keywords: Combining ability, Breeding program, Erysiphe graminis f. sp. Hordei, genetic resistance resources, Hordeum vulgare L., narrow sense heritability.

Category: Volume 27
Hits: 5507

Aperçu sur les approches utilisées dans la modélisation de l’écoulement de l’eau et du transport des solutés dans les sols

Revue Bibliographique

S. Kanzari ^1*

H. Sahraoui ¹

S. Ben Mariem ¹

R. Ilahy²

¹ Institut National de Recherche en Génie Rural, Eaux et Forêts, Rue Hédi Karray Ariana, Tunisie.

² Institut National de Recherche Agronomique de Tunis, Rue Hédi Karray Ariana, Tunisie.

Abstract - In countries where water shortages, poor quality of its waters and its soils are pronounced. The study of natural resource pollution risks is done through the use of numerical models. In this bibliographic review we present the main modeling approaches used for simulating water flow and solute transport in the soil and the various advantages and limitations of these models.

Keywords: Soil, Numerical models, Bibliographic Review.

Résumé - Dans les pays où les problèmes de pénurie d’eau existent et où la qualité des eaux et des sols est souvent médiocre. L’étude des risques de pollution des ressources naturelles passe par l’utilisation de modèles mathématiques. Dans cette revue bibliographique, on présente les principales approches de modélisation utilisées pour la simulation de l’écoulement de l’eau et du transport des solutés dans les sols ainsi que les différents avantages et limites de ces modèles.

Mots clés: Sol, modèles numériques, revue bibliographique.

Category: Volume 27
Hits: 7898

Effet de la provenance et du solvant d’extraction sur la teneur en composés phénoliques et les potentialités antioxydantes des graines de fenouil (Foeniculum vulgarae Mill.)

I. BETTAIEB REBEY*

J. SRITI

B. BESBESS

K. MKADDMINI HAMMI

I. HAMROUNI SELLAMI

B. MARZOUK, R. KSOURI

Laboratoire des Plantes Aromatiques et Médicinales, Centre de Biotechnologie de Borj-Cédria, BP 901, 2050 Hammam-Lif, Tunisie

Abstract - Fennel (Foeniculum vulgarae Mill.) seeds of two geographic origins, Tunisia and India (IFS), were studied regarding their phenolic content and antioxidant potentialities. Seed phenolic contents and antioxidant activity appeared to be accession and solvent dependent. Extraction with 60% ethanol led to the highest polyphenol and flavonoid contents, respectively for Tunisian fennel seeds and Indien fennel seeds. DPPH scavenging activity, chelating ability and reducing power were maximal in 60% ethanol for both Tunisian and Indian fennel seeds. HPLC analysis revealed several phenolic compounds in F.vulgarae seeds, with quercetin-3-O rutinoside as major phenolics in Tunisian and Indian fennel seeds, respectively. Thus, phenolic composition of fennel seeds is also origin dependent. The overall results suggest the exploitation of fennel seeds as a low-cost renewable source for industrial processing in the fields of food industries and pharmaceuticals.

Keywords: Foeniculum vulgarae Mill, phenolic, solvant, provenance, antioxidant activity.

Résumé - Les graines de fenouil d'origine tunisienne et Indienne ont été étudiées quand à leur contenu en polyphénols et leur potetialités antioxydantes. Nos résultats ont permis de montrer que le solvant d'extraction ainsi que la provenance affectent significativement les teneurs des graines de F.vulgarae en composés phénoliques, polyphénols totaux et flavonoïdes ainsi que les activités antioxydantes. Un effet bénéfique a été obtenu par l’addition de 40% d’eau à ces solvants (éthanol, acétone et méthanol), ce qui a permis une meilleure extraction quantitative des composés phénoliques et une activité antioxydante plus importante. Parmi les solvants à 60%, l’éthanol est le plus recommandé dans ce type d’extraction. De plus, les extraits de la variété locale sont doués d’une activité antioxydante plus interessante par rapport à celle de la variété Indienne avec une différence significative entre les deux. La quercetine-3-O rutinoside, composé phénolique majeur détecté dans les graines de fenouil locales, contribue aux activités antioxydantes élevées de cette espèce. Ceci suggère l’importance de l’utilisation des extraits de graines de fenouil comme une nouvelle source naturelle d’additifs alimentaires et d’antioxydants puissants en industries alimentaires.

Mots clés: Foeniculum vulgarae Mill, polyphénols, solvant, provenance, activité antioxydante

Category: Volume 27
Hits: 7003

Genetic relationships and structure among goat populations from southern Tunisia assessed using microsatellites

M. Nafti ¹*

Z. Khaldi ²

B. Haddad ¹

¹ Department of Animal Production and Fishery Sciences, Institut National Agronomique de Tunisie, Tunis, Tunisia.

² Department of Animal Production, Centre Régional de Recherche en Agriculture Oasienne Degueche, Tozeur, Tunisia.

Abstract - The objectives of this study were to characterize the genetic variability of oases goat population from two major oases regions of southern Tunisia to reveal any underlying population structure, and to evaluate genetic diversity parameters. Here we apply recent methodologies to analyze the polymorphism of eight microsatellites in 225 unrelated individuals belonging to four goat populations from southern Tunisia to ascertain their relationships and the relative genetic contributions existing between populations and geographic areas. The complete dataset showed a strong population structure derived from both different ancestral origins and some geographical patterns of recent gene flow.

The results showed a high genetic variability within the Tunisian goat population, with 64 different alleles and a mean number of 8 ± 3.07 alleles per locus. The values of heterozygosity (He and Ho) ranged from 0.54 to 0.80. Obtained result allowed saying that the greater part of genetic diversity came from individual variations between animal. Goat populations are characterized by a high genetic variability and should be safeguarded pool of genetic diversity.

Keywords: Microsatellite, Population Structure, Goat, Polymorphism.

Category: Volume 27
Hits: 7872

Histological characterization of resistance and some alternative control for leaf spot disease in olive tree

F. Ouerghi^1,4

A. Rhouma²

S. Aloui³

N. Rassaa³

I. Hennachi⁴

B. Nasraoui³

¹ Office de Développement Sylvo-Pastoral du Nord-Ouest, Béja, Tunisia

² Institut de l’Olivier, Tunis Station, Université de Sfax, Sfax, Tunisia

³ Ecole Supérieure d’Agriculture du Kef, Université de Jendouba, Kef, Tunisia

⁴ Institut National Agronomique de Tunisie, Université de Carthage, Tunis, Tunisia

Abstract - Field trail was conducted on the reaction of four olive cultivars (Chetoui, Picholine, Arbequina and Meski) toward the leaf spot disease caused by Fusicladium oleagineum. The results showed that higher disease incidence tends to be associated with thinner cuticle (r=-0.69) and higher trichome density (r=-0.58) and diameter (r=-0.9) of the infected plant. Glasshouse experiments were, then, carried out to study the effects of nitrogen and potassium fertilizing post-inoculation treatment and two antitranspirants (Linseed oil and Vapor Guard) pre-inoculation spray on leaf spot disease incidence on susceptible olive variety, cv. Meski. Results showed that potassium treatment and the Linseed oil 7% or Vapor Gard 3% spray reduced significantly the disease incidence by means of 67% and 80%, respectively.

Keywords: Olive, antitranspirant, nitrogen, potassium, Linseed oil, Vapor Guard, incidence disease.

Category: Volume 27
Hits: 5559

Grain Yield Assessment of Genotype by Environment Interaction of Tunisian Doubled-Haploid Barley Lines

W. Feriani ¹*

S. Rezgui¹

M. Cherif ¹

¹Department of Agronomy and Biotechnology, National Agronomic Institute of Tunisia, Av Charles Nicolle 43, 1082 Tunis, Tunisia.

Abstract - The objectives of this study were to evaluate barley grain yield performance and to assess the genotype × environment interaction for this trait. Fifty-seven (57) doubled-haploid (DH) barley lines derived from cross between two Tunisian cultivars ‘Roho’ and ‘Line 90’ were screened for grain yield in four environments. The trials were laid out in randomized block with three replications at Mograne and Boussalem during two consecutive growing seasons 2009-2010 and 2010-2011. The least significant difference allowed identifying more performing lines than the two parents and the three checks in each environment. Pooled analysis of variance across environments showed the presence of genotype × environment interactions which explained 17.23% of the total variation of grain yield. The additive main effect and multiplicative interaction model captured 84.47% of genotype × environment interaction sum squares. Barley lines DH24, DH48 and DH14 exhibited best and stable performances for grain yield over the four environments. These potential lines could be recommended as progenitors in barley breeding programs for high grain yield.

Keywords: Hordeum vulgare, grain yield performance, G×E interaction, AMMI model.