I. SOULI*^1,2

M. BAGUES²

B. LACHEHIB²

A. FERCHICHI³

¹ University of Tunis El Manar, Faculty of Sciences of Tunis, Department of Biology, 2092, El Manar II, Tunis, Tunisia

² Aridlands and Oases Cropping Laboratory, Institute of the Arid Areas of Medenine, Tunisia

³Rural Laboratory, National Institute of Agronomic of Tunisia, 43, Charles Nicolle, 1082, Tunis, Mahrajene, Tunisia

Abstract - The present study deals with the biotechnological valorization of dates having low market value, the production of the juice of eight cultivars of Tunisian date palm (Phoenix dactylifera L.) fruits grown in Gabes region (Oasis of Gabes, Tunisia) have analyzed their juice extracts for their nutritional quality, TPC, TFC, TCT and antioxidant activities using ABTS, DPPH, and FRAP assays. The analysis has shown that fruits of date cultivars contain a high amount of sugar (37.75-67.34 % FW) and the total sugars obtained by HPLC method showed that only DegletNour variety contains sucrose (non reducing sugar). But, a low content of fat (0.142–0.24% FW) and protein (1.19–2.89% FW) was found. For the minerals content, the fruit of dates are considered as very important sources of potassium and several minerals, followed in decreasing order by calcium, magnesium, sodium, iron, zinc and manganese. The obtained results have shown that all samples had the highest TPC, TFC, CTC, and the values of antioxidant of Trolox equivalent were higher in ABTS assay than those observed by DPPH and FRAP methods. A significant correlation was found between TPC, TFC, CTC and antioxidant activities. This syrup, produced by simple technological means, was rich in reducing sugars. These results suggest that this syrup, containing high nutriments value and natural antioxidants, might be more widely used by the food industry as a source of bioactive human health promoter phytochemicals.

Keywords: Date syrup, nutritional value, antioxidant activity

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D. Mansouri¹

N. Rassaa*²

A. Chalh¹

F. Bnejdi¹

M. El Gazzah¹

¹ Laboratory of biodiversity, biotechnology and climatic change, Biologic Sciences Department, faculty of sciences, university of Tunis El Manar, Tunisia.

² Laboratory of crop physiology, Higher School of Agriculture of El Kef, university of Jandouba, Tunisia

Abstract - Much is known about the physiological control of stomatal aperture to adjust water availability. In contrast, few studies were conducted on the stomatal development control to limit water loss. The objective of this study was to investigate stomatal density control in response to water deprivation for ten wheat genotypes: six varieties of Durum wheat and four varieties of Bread wheat. Three water regimes were applied. Separate statistical analysis of leaf area (LA) and stomatical density (SD) at three leaf stages showed significant differences between Durum wheat and Bread wheat and all varieties at each stage. Results reveled that SD increased with leaf stages. Drought reduced LA and induced various responses in terms of SD. In another hand, tolerance indices of SD was in concordance with results based on LA and reveled that only genotype "Mahmoudi" limited the stomatal development in response to water loss. These findings highlight the role that could be played to stomatal development during leaf expansion as a longer term to limit water loss from leaves. They also put the emphasis on the variability of stomatal response between genotypes. Finally, for eventual breeding program the key roles of SD should be considered to select better genotypes in terms of drought adaptability. Also, Mahmoudi should be recommended as potential genotype for drought tolerance.

Keywords: Water stress, Stomata density, Wheat, Variability.

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C. Kouki ¹

R. Bergaoui ¹

¹ Department of Animal Production, National Agronomic Institute of Tunisia, University of Carthage.

Abstract - 200 chickens, one day old, of Hubbard Classic heavy strain were distributed in 5 groups. A Quantitative feed restriction was used for broiler chickens slaughtered at different ages to estimate his impact on their performances, breast and thigh yields. Feed quantitative restriction (75% of a control group C fed ad -libitum during the experiment) was applied for two weeks as : R42 _21-35 chickens restricted from 21 to 35 d of age and slaughtered at 42 days , R49 _28-42 chickens restricted from 28 to 42 d and slaughtered at 49 days ; R56 _35-49 chickens restricted from 35 to 49 d and slaughtered at 49 days ; R63 _42-56 chickens restricted from 42 to 56 d and slaughtered at 63 days. After one week of re-feeding a sample of broilers of each group (C, R42, R49, R56, R63) was slaughtered in order to determinate the weight of the carcass, thigh, breast and to calculate the fat yields. Restricted broiler chickens R63 _42-56 have improved their feed conversion during the re-feeding period and had a similar body weight than those of ad- libitum group. Restricted broilers R56 and R63 improved significantly the gain weight during the re-feeding period. At 63 days of age the R63 had a similar breast and carcass weight to that of ad-libitum group contrary to others group having a breast and carcass’s weight significantly lower than ad-libitum broilers. The breast, thigh‘s and carcass yields of restricted chickens slaughtered at different age were not affected by feed restriction. This study showed that gizzard fat and abdominal fat weights of restricted group were significantly lower than those of ad-libitum group. However no significant difference between abdominal fat deposition yields of restricted and ad-libitum group to the different slaughtering ages. Mortality by ascites was reduced significantly at late ages (8 and 9 weeks of age) by feed restriction. A slaughter age of restricted broilers of 63 day may be effective for improvement of growth performances and reducing mortality of fast growth broilers breaded to late age for cutting.

Keywords: ascites, quantitative feed restriction, broiler chickens, slaughter age, breast and thigh yields.

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Conduite de l’irrigation de complément du blé dur dans quelques périmètres du nord de la Tunisie

M. Hammami ¹

A. Boughdiri ²

F. Ounaies ¹

S. SLIM ²

R. Soltani ¹

A. Sahbani ³

¹ School of Higher Education of Engineers in Rural Equipment of Medjez El Bab, University of Jandouba.

² School of Higher Education in Agriculture of Mateur, University of Carthage.

³ School of Higher Education in Agriculture of Mograne, University of Carthage.

Abstract - To ensure best water use effiency in the Northern Tunisia irrigated districts, several subsidies were provided for farmers. But though these encouragement, water productivity essentially for complementary irrigated winter wheat, remained insufficient. In order to assess the origins of such insufficient water productivity, diagnostic analysis were performed in three famous irrigated districts in the North of Tunisia where durum wheat is the predominant crop. The investigations were focused on the used irrigation systems, their suitability to the in situ conditions and on farm water management. Recorded results showed that sprinkler irrigation system is used in roughly 100% cases. Solid laterals with 3 bars nominal pressure sprinklers are the most frequent equipment. Water supplies were not always conforming to the crop water requirements. In fact, in some farms the diverted amounts were overestimated in december and/or under estimated in April. Water uniformity coefficient ranged within 68% and 80% and within 57% and 67,5% respectively in Medjez El Bab and Siliana irrigated districts. Recorded durum wheat productivity ranged within 2,8 and 4,7 ; 0,8 and 4,0 and 1,48 and 2,3 Kg/m³ respectively in Medjez, Mateur and Siliana irrigated districts.

Keywords: Northern Tunisia districts, durum wheat, on farm water management.

Résumé - Pour assurer l’autosuffisance en produits céréaliers tout en faisant face aux aléas climatiques en Tunisie, des subventions ont été accordés aux agriculteurs dans le but d’améliorer l’efficience d’utilisation de l’eau dans les périmètres irrigués. Toutefois, malgré ces incitations, la productivité de l’eau surtout en irrigation de complément du blé reste loin des prévisions. Afin de détecter les origines de cette faible efficience, des enquêtes et des suivis ont été réalisés dans trois périmètres irrigués du Nord : Medjez El Bab, Mateur et Siliana. Les investigations ont été focalisées sur l’adéquation des techniques d’irrigation adoptées aux conditions in situ et sur le pilotage des apports d’eau. Les résultats montrent que l’aspersion (avec des installations mobiles et asperseurs fixes) est pratiquée dans presque 100% des cas aux PPI Medjez et de Lakhmess (Siliana). Alors qu’à Mateur, les rampes souples avec arroseurs sur tri-pieds sont les plus fréquentes. Les apports d’eau n’étaient pas toujours conformes à l’évolution des besoins en eau de la culture avec des doses parfois excessives surtout au mois de décembre. L’uniformité de la distribution de l’eau à la parcelle était comprise entre 68% et 80%, entre 57% et entre 67,5% dans les PPI de Medjez El Bab et de Siliana respectivement. Outre la production en paille, la productivité de l’eau fluctuait entre 2,8 et 4,7 ; 0,8 et 4,0 et entre 1,48 et 2,3 Kg/m³ de grains aux PPI de Medjez, de Mateur et de Siliana respectivement. Ces rendements seraient plus intéressants si les compléments d’eau étaient assurés pendant les stades critiques de la culture. Un suivi des réserves en eau du sol permet certes de mieux ajuster les apports aux besoins et d’améliorer ainsi l’efficience de l’eau en irrigation de complément du blé.

Mots-clés: périmètres irrigués du Nord, blé dur, pilotage des apports d’eau

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Effet du fenugrec (Trigonella fænum græcum L.) sur les performances zootechniques et la mortalité des lapereaux en croissance

I.REKIK ¹

R. BERGAOUI ¹

¹ Department of Livestock Production: Agronomic National Institue of Tunisia: INAT, 43 Avenue Charles Nicolle, 1082 MAHRAJENE TUNIS - Tunisia

Abstract - The aim of this study was to test the impact of the fenugreek (Trigonella fænum graecum L) supplementation in the feed on growth performance and mortality in growing rabbits. 144 rabbits 35 days aged having a weight from 501.63g to 554.26g and were divided into three homogeneous groups receiving three diets (T₁, T₂ and T₃). Treatment T₁ is the control based on a standard concentrated feed and drinking water, treatment T₂ consisting of a mixture of standard feed and 4% fenugreek seeds soaked and then dried in an oven at 50 ° C for 4h and treatment T₃ is based on standard feed and water containing 4% water after soaking fenugreek.  The results showed a significant effect (P> 0.05) of the three diets on the average consumption of water by day and by rabbit (0.269; 0.308 and 0.335 respectively for T₁, T₂ and T₃₎. There is also a significant effect (p ≤ 0.05) in feed intake (g/rabbit/day) of the three groups (120.6 ± 3.57; 127.55 ± 4.89 and 112.47 ± 2.17 respectively for T₁, T₂ and T₃₎. In addition, the results showed that the fenugreek supplementation in the feeding of young rabbits has a significant effect on the growth of young rabbits as well as on animal mortality (p ≤ 0.05). Rabbits in group T₃ presented the highest final weight (2923.21 g ± 258.6) while the rabbits T₁present a weight of 2498, 28 g ± 156.97.The GMQ was influenced by the presence of fenugreek .The highest mortality is recorded at the T₁ group with 15% deaths throughout the experience while group T₃ have recorded 7.63% deaths.

Keywords: fenugreek – rabbits growth – GMQ – mortality

Résumé - Le but de la présente étude est de tester l’effet du fenugrec (Trigonella fænum græcum L) dans l’alimentation sur les performances zootechniques et la mortalité des lapereaux en croissance. On a utilisé 144 lapereaux âgés de 35 jours ayant un poids variant de 501,63g à 554,26g et qui ont été réparties en trois lots homogènes recevant trois régimes alimentaires (T₁,T₂ et T₃). Pour le traitement T₁ les lapereaux reçoivent un concentré standard et de l’eau potable, ceux du traitement T₂ reçoivent le concentré standard mélangé à 4% de graines de fenugrec trempées puis séchées dans l’étuve à 50°C pendant 4h. Les animaux du traitement T₃ le concentré standard et de l’eau contenant 4% d’extrait de graines de fenugrec. Les résultats ont montré un effet significatif (P>0,05) des trois régimes alimentaires sur la consommation moyenne journalière par lapereau de l’eau (0,269l; 0,308l and 0,335l respectivement pour T₁, T₂ and T₃₎. Les études ont montré aussi un effet significatif (P≤0,05) de l’ingestion alimentaire moyenne quotidienne des trois lots avec la consommation la plus élevée pour le lot T2 (soit 120,6g±3,57 ; 127,55g±4,89 et 112,47g±2,17 respectivement pour les lots T₁, T₂et T₃₎. En outre, les résultats ont prouvé que l’ajout de fenugrec dans l’alimentation des lapereaux a un effet remarquablement significatif sur la croissance des lapereaux aussi bien que sur la mortalité des animaux (P≤0,05). En effet, les lapereaux du lot T₃ ont présenté le poids final le plus élevé qui est de 2923,21g±258,6 alors que les lapereaux du lot T₁ sont les plus maigres sur toute la période d’engraissement présentant un poids de 2498,28g±156,97. Le GMQ est influencé par la présence du fenugrec. La mortalité des lapereaux la plus élevée est enregistrée au niveau du lot témoin avec 15 % de mortalité tout au long de l’essai alors qu’au niveau du lot T₃ nous n’avons enregistré que 7,63 %.

Mots-clés: fenugrec - performances zootechniques – GMQ – mortalité.

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F. ALJANE

N. SDIRI

Laboratoire d’Aridoculture et Cultures Oasiennes, Institut des Régions Arides de Médenine, Médenine 4119, Tunisia.

Abstract - In this study, the morphological characteristics, phytochemical composition and antioxidant activity of white (Morus alba L.), red (Morus rubra L.) and black (Morus nigra L.) mulberry fruits grown in arid regions of Tunisia was investigated. Fruit weight, organic acids, total soluble solids, reducing sugars, total phenolics, total anthocyanins, total flavonoïds, total carotenoïds and total antioxidant capacity (DPPH : 1,1 Diphényl 2 Pycril Hydrazil and ABTS : acide 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonique) were determined. The highest values of fruit weight (2.05 g), reducing sugars (5.02 and 5.75 g 100 g^-1 fresh weight), total phenolics (30.45 mg Gallic acid equivalent 100 g^-1 fresh weight) and total anthocyanins (10.05 mg cyanidin-3-glucoside equivalents 100 g^-1 fresh weight) were measured on Morus nigra. The white and the red mulberries have the highest levels of total soluble solids (19.20 %). Regarding malic acid and citric acid content, black mulberry fruits were the less acidic and determined 1.34 and 1.28 g/ l, respectively. Total antioxidant capacity by using DPPH methods of mulberry fruits was found between 66.62 % in Morus alba and 71.03 % in Morus nigra. The results of the study are helpful for attempting crop improvement in black mulberry for bringing to cultivation.

Keywords: Mulberry, Fruit weight, Organic acids, Reducing sugars, Total phenolics, DPPH, ABTS.

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