N. CHIHANI-HAMMAS ¹

L. HAJJI-HEDFI¹

Y. QING²

A. BADISS²

H. REGAIEG¹

N. HORRIGUE-RAOUANI ¹

¹ Biological Sciences and Plant Protection Department, Higher Agronomic Institute of Chatt-Mariem, B.P. 47, 4042, Sousse, Tunisia

² Agriculture and Agri-Food Canada (AAFC), Ontario, Canada

Abstract – Root-knot nematodes (RKN: Meloidogyne spp.) have a wide host range, what implies that multiple crops may be affected among them apple trees. Between 2013 and 2014, a nematological survey was carried out in apple trees from nurseries in Tunisia. Root galling caused by root-knot nematodes was observed. Infected tissues were examined and RKN species were identifiedThe morphological study based on perineal patterns of the females confirmed the presence of M. arenaria. In addition, the molecular identification was carried out and based on the internal transcribed spacer 1 (ITS1-5.8S-ITS2) gene. The sequences were compared with those of Meloidogyne arenaria in the GenBank database with high similarity (95%). This comparison confirmed the species identification and reconfirmed the morphological identification. Phylogenetic studies placed those populations with M. arenaria. To the best of our knowledge, this is the first report of this nematode associated with apple plant in Tunisia.

Keywords: ITS1, morphology, molecular identification, Phylogeny, Apple, Meloidogyne arenaria

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Effets de l’ablation de la queue sur les performances de reproduction des brebis de race Barbarine

Y. YAGOUBI¹

N. ATTI¹

¹ Carthage University, National Institute of Agronomic Research of Tunisia, Animal and Forage Productions Laboratory, rue Hédi Karray, 2080 Ariana, Tunisia.

Abstract – The fat tail of Barbarine ewes represents an obstacle to the natural mating, for that the assistance of an experimented shepherd is required. Hence, the aim of this study was to evaluate the effects of tail docking on Brown face Barbarine sheep performances. This experiment was conducted during July and August on 92 ewes, 30 months old, divided into three groups. In the first group (SQ), ewes underwent the tail docking at birth and the mating occurred without help of shepherd; in the QSB and QB groups, ewes were not subject to the tail docking. The mating for QSB occurred without help of shepherd however, for QB group, the shepherd assisted the ram during the mating. At the experiment beginning, ewes’ body weight (BW) averaged 40 ± 5 kg, their body condition lumbar score (BCS) was 1.8 ± 0.6, and the caudal score was 4 ± 0.8. All ewes received the same diet during the experiment. The ewes’ oestrus was daily controlled. They were regularly weighed and their body condition score was noted from the ewe’s mating to lambs’ weaning. High rates of oestrus were observed during the first 17 days of control which were 81, 73 and 73% for SQ, QSB and QB, respectively. Moreover, the returns of oestrus rates were low, limited to 3, 10 and 12% for SQ, QSB and QB. The fertility rate was 84.4, 86.7 and 86.7 % and the rate of prolificacy was 100, 100 and 103 % for SQ, QSB and QB, respectively, without significant difference between groups. As the fertility rates of ewes with and without a tail, assisted and unassisted by the shepherd in fight were similar, the presence of the shepherd in the mating seems unnecessary, at least in the natural mating season. The lamb’s growth parameters were similar among groups.

Keywords: fat-tailed sheep, tail docking, body condition score, oestrus, fertility

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Contribution de l’Amélioration Génétique à la Durabilité de la culture de blé dur en Tunisie

Bibliographic Review

R. HAMMAMI¹

M. S. GHARBI¹

¹ Laboratoire des Grandes Cultures Institut National de la Recherche Agronomique de Tunis- Université Carthage, Rue HédiKarray –2049 Ariana- Tunisie

Abstract – This bibliographical summary traces the contribution of genetic improvement to the sustainability of Tunisian durum wheat since the start of the cereals breeding program in 1906. Cereals are a major component in Tunisian agriculture in terms of grown area, the related socio-economic activity and it’s a main source of food stuff. Breeding yielded a high number of varieties and lines, through either crossing local cultivars or native parents and foreign material. Targeted crosses significantly enriched the gene pool manipulated at the program level and resulted in genetic gain in terms of productivity, disease resistance and drought tolerance. As a result, the grain yield of the recently released varieties is three to four times that of old varieties grown in the early twentieth century before the introduction of semi-dwarf wheats. Mexicain wheats due to theirhigh genetic yield potential, their wide adaptation and their better tolerance to biotic and abiotic constraints, currently occupy more than 90% of the areas planted. Thus, the impact of genetic improvement on Tunisian cereal production and particularly that of durum wheat is undeniable. However, the country is far from achieving its self-sufficiency, for this reason, there is an urgent need for the integration of the genome analysis-based tools to accelerate breeding process.

Keywords: Durum wheat, Breeding, sustainability, yield, diseases tolerance

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F. BEN ABDERKADER¹

G. KAIRO²

S. TCHAMITCHIAN²

M. BONNET²

M. COUSIN²

N. BARBOUCHE¹

L. P. BELZUNCES²

J. LUC BRUNET ²

¹ National Institute of Agronomy of Tunisia, Bioagressors and Integrated Protection in Agriculture (BPIA), University of Carthage, Tunis –TUNISIA

² INRA, UR 406 Abeilles & Environnement, Toxicologie Environnementale, Avignon, 84914, France.

Abstract – Many problems have been reported on honey bees colonies including fertility problems of queens resulted in production failure. Pesticides can be the cause of this failure in connection with the quality of sperm drone. Thus, the aim of this study was to assess the influence of exposure to syrup contaminated with clothianidin at 0.1 µg/L on semen parameters of drones. Results showed a significant decrease of semen volume and sperm concentration and an increase in sperm mortality rate. As for the energetic state, clothianidin increased cell redox potential, the ATP content of spermatozoa as well as the lactate dehydrogenase activity (LDH). It was concluded that exposure to clothianidin during the sexual maturity of drones could affect the semen quality.

Keywords: pesticides, drones, spermatozoa, fertility, metabolic state

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