Category: Volume 66
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Effect of irrigation with olive-mill waste-water on physiological and biochemical parameters as well as heavy-metal accumulation in common bean (Phaseolus vulgaris L.)

F. TAJINI^1*

A. OUERGHI^{1, 2}

K. HOSNI³

¹Unité de Physiologie Fonctionnelle et Valorisation des Bio-ressources : UR17ES27(ISBB), Beja- 9000,Université de Jendouba, Tunisie.

²Ecole Nationale Supérieure de Chimie de Paris, Chimie Paristech – PSL Research University, 11 rue Pierre et Marie Curie, 75005 Paris, France

³Unité de Physiologie et Biochimie de la Réponse des Plantes aux Contraintes Abiotiques, Faculté des Sciences de Tunis El Manar, Université de Carthage, 2092. Tunisie.

Abstract - The olive-mill waste-water (OMW) is rich in organic matter as well as mineral salts of potassium, sodium and magnesium. Thus, OMW is beneficial for the increase in biological activity and for restoring the fertility of soils. The response of two common bean genotypes (Phaseolus vulgaris L.), namely Coco blanc and BRB17, to irrigation with different concentrations of OMW ranging from 0 to 500 ml l^-1, was studied in greenhouse condition. Growth, leaf area, photosynthesis, stomatal conductance, chlorophyll content index, contents of nitrogen, proline, soluble sugars and heavy metals (Cu, Cd, Pb, Ni, Zn and Fe), were analyzed in shoots, roots and pods. Our results indicated that the OMW was toxic for common bean under irrigation, and increasing OMW concentration in the culture resulted in a parallel decrease in plant growth and leaf photosynthesis parameters, at 500 ml l^-1the decrease was above 50%. The heavy metals in OMW were translocated from roots to shoots and pods (food organs), and increasing OMW resulted in an increase in content of heavy-metals in plants, with the highest accumulation being in roots. The results showed that Coco blanc was more susceptible than BRB17 to the toxic effects of OMW (83.3% in shoot; 81.8% in root and 82.7% in leaf area and decrease in mineral nutrition NT=68.1% at 500ml l^-1). The study revealed the need for OMW valorization strategies, aimed at treating these effluents for use in soil fertility restoration and limiting toxic effects of OMW for production of safe food.

Keywords: Growth, gas exchange, heavy metal accumulation, olive mill wastewater, Phaseolus vulgaris L., toxic factor.

Category: Volume 66
Hits: 4067

Insecticidal activity of several Tunisian essential oils against two major pests of stored grain Rhyzopertha dominica (Fabricius, 1792) and Tribolium castaneum (Herbest 1797)

S. NCIBI¹

N. BARBOUCHE¹

S. HAOUEL-HAMDI²

M. AMMAR¹

¹Laboratoire de Bio-Agresseurs et Protection Intégrée en Agriculture, Institut National Agronomique de Tunisie, Université de Carthage, 43 Avenue Charles Nicolle 1082, Tunis, Tunisie

² Laboratoire de Biotechnologie Appliquée à l'Agriculture, Institut National de la Recherche Agronomique de Tunisie ,Université de Carthage, Rue Hedi Karray, 1004 El Menzah Tunis

Abstract - Essential oils (EOs) extracted by hydrodistilation from fifteen Tunisian plant species namely Pistacia lentiscus, Artemisia arborescens, Artemisia herba-alba, Cupressus sempervirens, Juniperus communis, Pelargonium graveolens, Lavandula angustifolia, Mentha pulegium, Rosmarinus officinalis, Salvia officinalis, Thymbra capitata, Laurus nobilis, Myrtus communis, Citrus aurantium, Ruta chalepensis, are tested for their insecticidal activities on adults of both pests of stored grains Rhyzopertha dominica (Bostrichidae) and Tribolium castaneum (Tenebrionidea). Fumigant toxicity bioassays showed that R. dominica is more sensitive towards these EOs than T. castaneum. L. angustifoliais the most effective essential oil followed by R. chalepensis essential oil with LC₅₀values of 11.14 and 14.82μl/l air,respectively. Moreover, M. pulegium and R. officinalis oils also exibited significant fumigant toxicity with LC₅₀ values of ~ 16.6μl/l air. Besides, T. castaneum was more tolerant to these EO except those from R. chalepensis(LC₅₀ = 21.03 μl /l air) and M. pulegium(LC₅₀ = 49.84μl /l air). Repellent activity against both insects showed th atC. sempervirens EO was the most effective against T. castaneumcompared with other treatments; it caused 100% repellency after 6 hours of exposure to the dose 0.15μl /cm² while M. communis EO was the most effective againstR. dominica after 24 hours of exposure at the dose of 0.076μl /cm². The ingestion toxicity of R. chalepensis and M. pulegium EOs showed the most important activity against the two insects withLC₅₀values of 131.86μl / l and 55.5μl / L forR. dominica respectively and with LC₅₀values of 121.8μl / l and 178.46μl / l for T. castaneum respectively. These results pointed out that among EO tested, those extracted from R. chalpensis, M. pulegium could be the target of further research to demonstrate their efficacy as biopesticides against stored grain insects.

Keywords: bioinsecticide, essential oils, Ruta chalepensis, Mentha pulegium, Rhyzopertha dominican, Tribolium castaneum

Category: Volume 66
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An analysis of sediment production and control in Rmel river basin using InVEST Sediment Retention model

S. BOUGUERRA¹

S. JEBARI²

J. TARHOUNI¹

¹National institute of agronomy of Tunisia. Tunis. Tunisia.

²National Research Institute for Rural Engineering. Water and Forestry. Tunis. Tunisia.

Abstract - Water erosion is a significant menace to land and water resources. It has a significant impact on agricultural production and sustainability of surface water resources under a Mediterranean climate system, especially in Tunisia. Identification and prioritization of critical erosion areas is an important aspect for policy makers. The aim of this paper is to determine the most vulnerable areas to soil erosion in the Rmel river basin situated in the Northeast of Tunisia, and to assess the effect of a catchment-scale implementation of soil conservation measures on soil loss and sediment yield. We used the InVEST (Integrated Valuation of Environmental Services and Tradeoffs) sediment retention model to provide spatially-explicit predictions of soil loss and sediment yield.Considering soil and water conservation measures, soil loss and sediment export decreased respectively by 4 and 0.9 ton/ha/year and sediment retention by 2 ton/ha/year.Comparing this value with the reservoir capacity, it indicates that risks related to reservoir sedimentation will also decrease.

Keywords: Sediment yield, sediment retention, InVEST SDR model, soil loss

Category: Volume 66
Hits: 5772

Phenotypic diversity of barley (Hordeum vulgare L. subsp. vulgare) landraces from the Center and the South of Tunisia and identification of potential area of on-farm conservation

I. BOUHAOUEL ^1,2*

M. MEDINI ²

H. BELHADJ ^1,2

O. SLAMA AYED ¹

C. JABRI ²

H. SLIM AMARA ¹

¹University of Carthage, National Agronomic Institute of Tunisia, Department of Agronomy and Plant Biotechnology, Genetics and Cereal Breeding Laboratory, 43 Charles Nicolle Street, 1082 - Tunis Mahragene, Tunisia.

²National Gene Bank, Leader Yasser Arafat Boulevard, 1080 - Charguia 1, Tunisia.

Abstract-Landraces represent a crucial reservoir of biodiversity and source of novel gene alleles for breeding programs and for sustainable agriculture towards climate change. In this context, a morphological characterization of 882 barley accessions collected from the Center (Mahdia) and the South (Gabes) of Tunisia was conducted using 24 qualitative and 3 quantitative traits related to the spike and grain characteristics. The phenotypic diversity was determined by the Shannon-Weaver diversity Index (H')and revealed that spike length (H′ = 0.83), aleurone color (H′ = 0.73) and intensity of the anthocyanin coloration of awn tips (H′ = 0.71) werethe most polymorphic traits. The genetic diversity within populations (H_S= 0.25) represented the major proportion of the total genetic diversity (H_T= 0.28). Data showed considerable gene flow (N_m = 4.17) and low genetic differentiation (G_ST = 0.11). This suggests that Tunisian barley landraces are closely related but have an intra-population variability.Regarding the surveyed areas, Mahdia showed a slightly higher phenotypic diversity compared to Gabes. In particular, the locality of Menzel Habib showing the highest polymorphismwas proposed as suitable place for the in situ/on-farm conservation of local germplasm. The factorial correspondence analysis showed that morphological markers play a relevant role in discriminating accessions than geographic regions. Row type, spike shape and density, rachilla hair type, and grain and aleurone color were the discriminatorytraitsofTunisian barley landraces.

Keywords: Barley,in situ conservation,landraces, morphological traits, Shannon-Weaver diversity index (H′)

Category: Volume 66
Hits: 3537

Place of modules dedicated to the environment in the curriculum of six Moroccan universities and analysis of environmental knowledge to teach

Place des modules dédiés à l’environnement dans le programme d’enseignement de six universités marocaines et analyse de savoir environnemental à enseigner

I. ZAHIR^1*

O. IYADAYEN¹

M. ETTAKI¹

M. MONASEF¹

¹Polyvalent laboratory in research and development, Department of Biology, Poly-disciplinary Faculty, Sultan MoulaySlimane University, BeniMellal, Morocco

Abstract -The study aims to explore the practices of the Moroccan university about the environment. To reach this, the research was based on the analysis of university curricula, the analysis of the environmental knowledge to be taught. The results show that at the scale of six Moroccan universities, there are 545 sectors, of which 345 (63.3%), do not offer environmental lessons. While the discipline that carries the highest number of modules related to the environment is geography, followed by those of biology and geology, all levels combined with predominance at the level of the license. The analysis of some environmental lessons of these three disciplines taught at the faculties of Sultan MoulaySlimane University in Beni Mellal and the Sidi Mohammed Ben Abdallah University in Fez shows that these courses are characterized by their wealth of information and environmental concepts.

Keywords: Environmental education, university education.

Category: Volume 66
Hits: 3392

Evaluation of antioxidant enzymatic activity in plasma of the dromedary (Camelus dromedarius) in Tunisia

K. BARHOUMI^1*

F. TANNICH¹

O. SOUILEM¹

¹Laboratory of Physiology and Therapeutics. University of Manouba. Ecole Nationale de Médecine Vétérinaire de Sidi Thabet,

Abstract – This study aimed to evaluate the antioxidant status in dromedary. The activity of some enzymes such as superoxide dismutase, catalase, peroxidase and some metal ions (calcium, magnesium, iron) were explored. A total of 40 dromedaries were divided into 4 groups: 10 young males (aged less than 1 year), 10 adult males (age varied from 3 to 5 years), 10 lactating females and 10 pregnant. The antioxidant status was assessed according to the age of the animal, the sex and the physiological situation of the female (pregnant, lactating). The results show an average activity in superoxide dismutase, catalase and peroxidase of 180.21 ± 8.21 kU/L, 105.84 ± 4.25 kU/L and 102.27 ± 4.75 mU/ L respectively. These enzymatic activities were more important in young animals (vs. adults) (p = 0.012, 0.025, 0.026 for superoxide dismutase, catalase and peroxidase respectively) and lactating (vs pregnant) females (p = 0.015, 0.028, 0.026 for superoxide dismutase, catalase and peroxidaserespectively). Besides, the variations of some metal ions were correlated positively; whereas no, statistically significant, variation was detected according to the sex of the animal (p = 0.07, 0.06, 0.12 for superoxide dismutase, catalase and peroxidase respectively).

Keywords: dromedary, superoxide dismutase, catalase, peroxidase, metal ions, plasma

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