Analyse qualitative des indicateurs de dégradation des oasis de Nefzaoui et étude quantitative de leurs impacts sur le niveau socio-économique des agriculteurs de la région.

N. KARBOUT^1,2*

L. DHAOUIDI³

A. BOUGHDIRI⁴

M. JAOUED¹

M. MOUSSA¹

H. BOUSNINA² 

¹Institute of Arid Area, Mednine, Tunisia.

²National Institutes in Agronomy of Tunisia, Carthage University, Tunisia

³ Regional Research Center for Oasis agriculture of Deguache, Tunisia.

⁴School of Higher Education of Agriculture in Mateur, Tunisia

Abstract – This research aims to identify the farmers’ perceptions on the degradation in oasis agrosystems, its impacts on the farmers’ livelihoods and the factors that may hinder the farmers’ decisions of adopting sustainable management practices. The case study was carried out in Nefzaoua oasis southern Tunisia. 179 from 286 agriculture semi-structured surveys were conducted with the farmers. The results showed that 100% of farmers are aware of the degradation process in their oases; they recognized the scarcity of water, the salinity of the soil, followed by the loss of biodiversity as the most visible signs of degradation. The degradation of the oasis has resulted in a reduction in productivity and a deterioration of farmers' livelihoods. Agricultural practices adopted by farmers were limited to the use of sandy amendments. This explains the state's intervention through capacity building programs for farmers and policies that encourage the sustainable development of the oasis and strengthen the active involvement of farmers in the decision-making process regarding the oasis management.

Key words: Farmers’ perception, oasis agrosystems, degradation, sustainability, date palm, Nefzaoua oasis, Tunisia

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Adaptation au changement climatique et impact sur la durabilité de l’agriculture pluviale dans le Bassin versant d’Oued Oum Zessar, Sud-est de la Tunisie

N. OUNALLI^1* 

M. SGHAIER²

¹Institut National de Recherche Agronomique de Tunis, Laboratoire d’Economie.

² Institut des Régions Arides Médenine, Laboratoire d’Economie et Sociétés Rurales.

Abstract - Tunisia has ratified the international conventions on climate change and has made significant efforts in developing national adaptation strategies to this phenomenon (MEP, 2001). The challenge of climate change concerns not only the integrity of ecosystems but also socio-economic activities, food security, the health and safety of populations, economic development, the migration of populations and the aggravation of political instability. , which essentially depend on the adaptive capacities of the communities concerned (Benjamin, 2007). In this context, this paper consists of a contribution to the impact assessment and the analysis of adaptation strategies of the local population of the Oued Oum Zessar watershed of the governorate of Medenine to climate change. The methodological approach adopted was based on data from socio-economic field surveys and a participatory consultation workshop with a multidisciplinary team composed of different experts. This workshop focused on a discussion of different scenarios related to natural resource development and conservation programs. Identification and selection of indicators of sustainability of agricultural production systems in the watershed were conducted. Land use functions, development indicators for these functions, and water and soil conservation scenarios are identified. The weighting and prioritization of criteria and indicators were also carried out during this participatory workshop.

Key words: Assessment, indicators, land use functions.

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W. TAYEB ^1*

S. BRAHIM ²

I. CHAIEB ³

¹National ¹Laboratory of Biochemistry, «UR Human Nutrition and metabolic disorders”, Faculty of Medicine», University of Monastir (TUNISIA).

²Laboratory of Biochemistry, «Unité 05/UR/09-09, Mécanismes Moléculaires et Pathologies », Faculty of Medicine, University of Monastir (TUNISIA).

³Regional Research Center of Horticulture and organic agriculture, Chott Mariem, University of Sousse, (TUNISIA)

Abstract – 2,4-Dichlorophenoxyacetic acid (2,4-D) and its derivatives are herbicides widely used to control the growth of broadleaf and woody plants. Although 2,4-D is well known to be moderately toxic, little information is available on its cytotoxicity and mechanism of its toxicity. The aim of the present study was to investigate the cytotoxic effects of different forms of 2,4-D on a laryngeal carcinoma cell line: HEp-2 cells. Cells were treated with 2, 4, 8 and 16 mM of 2,4-D; 2,4-D Na and “Désormone lourd”; cell viability and induction of apoptosis were determined. Apoptosis was analyzed by cell nuclear staining with Hoechst 33342 dye and DNA fragmentation. The second purpose of our study was to compare the cytotoxicity of 2,4-D alone or modulated by the cytoprotective effects of additional antioxidants such as vitamin-C. Our results indicated that (i) 2,4-D can be responsible for oxidative damage to HEp-2 cells (ii) 2,4-D is cytotoxic for HEp-2 cells in a concentration and time-dependant manner (iii) 2,4-D exerts its cytotoxic effects by the induction of apoptosis (iiii) antioxidant compounds should be associated to herbicide formulations to decrease their deleterious effects on cells.

Keywords: pesticide; cytotoxicity; HEp- 2 cells; IC₅₀; apoptosis.

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Analyse et modélisation de la production du liège en vue d’une gestion optimale: cas de la forêt de Ain Snoussi,Nord Ouest de la Tunisie.

B. STITI ^1,3

H. CHAAR ²

A. KHALDI ¹

B. HENCHI ³

¹Institut National de Recherches en Génie Rural, Eaux et Forêts (INRGREF), BP10. Ariana.Université de Carthage.Tunisie

²Institut National Agronomique de Tunisie (INAT). BP 48, Tunis 1082.Université de Carthage.Tunisie.

³Faculté des sciences de Tunis (FST). El Manar. 2092.Tunis. Université El Manar. Tunisie.

Abstract – Cork is a non-wood forest productwidely used in industry. Despite its economic importance, research in relation to corkgrowth and production has been scarce in Tunisia. The objective of this study is to characterize cork thickness and to fit a non-linear model for predicting cork weightas a support for management decision. For this purpose, samples of reproduction cork were examined on 233 trees selected in Ain Snoussicork oak forest, situated in Northwestern Tunisia. First, thickness was measured on cork samples then the former were sorted into 7commercial classes according to cork thickness.Volume and weight of cork samples were calculated as well as stripped surface which let to estimate cork productivity per metre square of stripped surface. The results showed a low mean cork thickness (23.8±2.3mm) considered unfit for stoppers. Moreover, thickness was estimated to be below the limit required for stoppers production (27 mm) in 69% of cork. Productivity average, equal to 5.16±0.59kg per m², was low. Besides, a model was fit betweenreproduction cork weight and three principal tree parameters: circumference over bark at breast height, debarking height and cork age.Thus, it is recommended to extend cork rotation in this forestto increase cork thickness and to monitor efficiently the cork debarking operation with a reasonable debarking index.Indeed, by means of the explanatory parameters of the established model it would be conceivable to define the duration of the rotation period that best suits each forest.

Key words: QuercussuberL., cork thickness, industrial stoppers, Productivity, non-linear regression, debarking operation, forest management.

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M. BEN-JABEUR*¹

Z. KTHIRI¹

L. SOMAI-JAMMALI²

W. HAMADA¹

E. AIT BARKA³

C. JACQUARD³

¹Laboratory of Genetics and plant breeding, National Institute of Agronomy (INAT), 43, Av Charles Nicolle, 1082 Tunis, Tunisia

²Ministry of Health, Unit of Environmental Health and Environmental Protection, Bab saadoun 1006 Tunis, Tunisia

³Unit of Induced Resistance and Plant Bioprotection, EA 4707, SFR Condorcet FR CNRS 3417, University of ReimsChampagne-Ardenne, Reims, France

Abstract – Biostimulants inducing plant defences is among the promising approaches to reduce the chemical pesticides use in wheat protection against Septoria leaf blotch caused by the hemibiotrophic Zymoseptori tritici. Within this scope, the effect of seed coating with the bacterium Paraburkholderia phytofirmans (PsJN strain) or thyme oil on triggering wheat systemic resistance to Septoria leaf blotch under controlled conditions was investigated using histopathological, physiological and biochemical approaches. Both products reducednecrosis, pycnidial density,associated with induction of programmed cell death, papillae accumulation in the biotrophic stage, and lowerperoxidase activity, H₂O₂, catalase and phenolic content in the necrotophic stage. Thyme oilinduced systemic acquired resistancewhile PsJN strain triggered induced systemic resistance to Septoria leaf blotch. 

Keywords: Biostimulants; programmed cell death; papillae; peroxidase; catalase; hemibiotrophic

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Effets des pratiques d’élevage sur le bien-être animal et la qualité du lait chez la vache Holstein en Tunisie

C. DAREJ¹

N. M’HAMDI¹

K. ATTIA¹

S. HAMZAOUI¹

H. M’HAMDI²

K. MRABET³

R. BOURAOUI⁴

¹National Agronomic Institute of Tunisia, 43 Av Ch Nicolle, 1082 Tunis, Tunisia

²Ministry of Agriculture, Water Resources and Fisheries, Tunisia (MARHP); CRDA of Ben Arous, Tunisia

³Ministry of Agriculture, Water Resources and Fisheries, Tunisia (MARHP); CRDA of Sousse

⁴Higher School of Agriculture of Mateur, Univerity of Carthage

Abstract – The main objective of this work is to study the effect of rearing practices on animals’ welfare and cow milk quality. A total of 53 farms were surveyed and 665 milk samples (1 sample per cow) were taken for physico-chemical and bacteriological analyzes. The results indicate that the sampled farms have an average forage area of ​​about 4.3 ha, and an average herd size of 12.55 dairy cows with an average production of about 17.79 l/cow/day. The analysis of feed allowed identifying 4 types of ration (R1, R2, R3, R4) with use frequencies of 11.32, 75, 47, 5.66 and 7.55% respectively. The results of physicochemical and bacteriological analyzis revealed an average density of 1028.2, average levels of fat and crud proteins of 38.6 g/l and 30.3 g/l respectively, a high rate of urea of 44.26 mg/dl, an average pH of 6.72 and a somatic cell count of 1656.87 × 10³ cell/ml. In terms of animal welfare, 86% of farms have an average state of good welfare and 14% have a bad state of animal welfare. The state of well-being at the farms visited varies from good to excellent. The average avoidance distance vary from 2 to 3 m with almost 56% of animals can be touched.

Key words: Breeding practice, feed, hygiene, milk, welfare, cow, Tunisia.

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