Effet de la Saison de Culture et de la Densité des Plants sur les Adventices et la Production de la Cucurbite oléagineuse Citrullus lanatus (Thunberg) Matsum. & Nakai (Cucurbitaceae)

Citrullus lanatus a été cultivée sur 2 périodes de l’année (saison 1 : d’Avril à Juillet et saison 2 : de Septembre à Décembre 2006) à la ferme expérimentale de l’Université d’Abobo-Adjamé en Côte d’Ivoire. Ces études visaient à déterminer la densité de la cucurbite qui assure un contrôle biologique des adventices et celle qui permet une meilleure productivité de cette culture mineure. Le dispositif expérimental est un bloc complètement randomisé, subdivisé en parcelles élémentaires de 6 m × 6 m avec trois répétitions par traitement. Sept paramètres agronomiques chez la cucurbite et la densité d’adventices (estimée uniquement au cours de la 1ère saison) ont été analysés dans trois systèmes culturaux. L’analyse a été suivie de tests de comparaisons multiples. Il en ressort que l’augmentation de la densité de la cucurbite réduit le nombre d’adventices. Les résultats montrent également que les composantes de rendement de la cucurbite, excepté le nombre de fruits à l’hectare (NFHa), diminuent avec la densité de semis. Cette diminution est plus prononcée à la deuxième saison. Sur la base des résultats obtenus, il a été suggéré de cultiver C. lanatus, à forte densité pour lutter contre les adventices et à faible densité pour obtenir des effets bénéfiques au niveau de son rendement.Mots-clés : Citrullus lanatus – densité – adventives – rendement

Observations préliminaires de la variabilité entre quelques morphotypes de voandzou (Vigna subterranea L. Verdc., Fabaceae) de Côte d'Ivoire

Preliminary observations of variability between some morphotypes of bambara groundnut (Vigna subterranea L. Verdc., Fabaceae) from Côte d’Ivoire. Bambara groundnut (Vigna subterranea L. Verdc.), is a food legume mainly cultivated by women for whom it represents a source of income for the household. In Côte d’Ivoire, the cultivation of bambara groundnut is located in the western and northern parts of the country. These zones are characterised by contrasted agroecology including tropical rain forest and dry savanna. In these zones, bambara groundnut plays a key role in both food and culture of peoples. Four morphotypes of Côte d’Ivoire (ICU, BPR, RBU, NFU) were used in a preliminary study to assess the phenotypic variability between morphotypes. For each morphotype, 100 individuals were sampled to analyse 26 agromorphological traits selected from the list of bambara groundnut descriptors. Results of statistical analyses showed an important variability among morphotypes suggesting that 22 of these characters could be powerful to distinguish diversity among bambara groundnut morphotypes of Côte d’Ivoire. Three morphotypes (ICU, BPR and RBU) show a shorter reproductive cycle than the other (NFU). In our experimental conditions, morphotypes with a shorter reproductive cycle give a higher percentage of matured pods (87 to 95%), compared to morphotype NFU (60%). The morphotype ICU was particularly earlier, maturing 90 days after sowing (DAS), whereas the long reproductive cycle morphotype (NFU) required about 137 days. Based on the analysed agronomic traits, possibilities to improve bambara groundnut yield and to promote its cultivation in Côte d’Ivoire are discussed

Estimating Additive and Dominance Variance for Litter Traits in Purebred California White Kits Using Different Models

Reproductive and growth records of 82 purebred California white kits were used to estimate additive and dominance genetic variances using BULPF90PC-PACK. Estimates were obtained for litter size at birth (LSB) and at weaning (LSW); litter weight at birth (LWB) and at weaning (LWW); individual kit weight at birth (IKWB)and at weaning (IKWW)as well as neonatal (Nil) and morlality at weaning (WM). Two mixed model equations were adopted. The first model included fixed effects and random effects identifying inbreeding depression, additive gene effect and permanent environmental effects. The second model was similar to the first model, but included the dominance genotypic effect. Estimates of heritability from sire component of variance for LSB, LSW, LWB, LWW, IKWB and IKWW were 0.4810.53,0.41/0.44, 0.5010.55 ,0.491NA, 0.4410.47 and 0.48/0.56 from model 1 and 2 respectively. Proportions of dominance effect to total phenotypic variance from the dominance model were 0.222, 0.453, 0.206, 0.349, 0.417 and 0.521 for LSB, LSW, LWB, LWW, IKWB and IKWW respectively. Dominance effects, which are not transferable through gametes (haploid entities) but are recreated at random in the offspring, were found to influence the litter traits analyzed. Therefore, genetic evaluation with the dominance model (Model 2) was found more appropriate than the animal model (Model 1). Keywords: Additive, Dominance, Heritability, Inbreeding, Rabbi

Optimization of ISSR marker for African edible-seeded Cucurbitaceae species’ genetic diversity analysis

We applied a molecular approach using inter-simple sequence repeat (ISSR) markers on three African edible-seeded cucurbits (Citrullus lanatus L. Matsumura and Nakai, Cucumeropsis mannii L. Naudin and Cucumis melo var. agrestis L. Naudin). To obtain clear and reproducible bands on 1.5% agarose gels, we screened 21 ISSR primers and three parameters (annealing temperature, gel tray, and voltage and running time). The resolution of 11 ISSR markers was performed, with optimal annealing temperature (Ta) varying from 50 to 52°C. The best combination to obtain clear and well-distinguished band patterns was 1.5% agarose gel with a 20-lanes tray (6 mm width) at 80 V for 5 h. Applying the 11 ISSR primers on DNA extracted from an accession of C. lanatus, 66 bands with 4 to 11 bands per primer was observed.Keywords: ISSR, Cucurbits, genetic diversity, molecular markers, optimizatio

Relationship Between Gestation Length and Birth Weight in Nigerian Sheep and Their Crosses

Effect of genotype and birth weight on gestation length was evaluated using Nigerian breeds of sheep and their crosses. The study was carried out at the Sheep Project Unit of Small Ruminant Research Programme (SRRP) of National Animal Production Research Institute (NAPRI), Ahmadu Bello University, Shika-Zaria. The sheep breeds used were Balami, Uda and Yankasa. Heat (estrus) detection was carried out twice daily; in the morning (07:00-08:00 hours); and in the evening (16:00-17:00 hours) using apron fitted rams to pick does on heat. A total of 56 lambs were used for this study. The data obtained were subjected to analysis of variance using General Linear Model and Correlation Procedure of SAS. All the genotypes had similar gestation length with values between 150.3±0.61 days and 153.3±0.60 days, except for Balami pure breed (BAL X BAL) lambs that recorded a shorter gestation length (137.1±0.81 days). There was a wide variation in the birth weight of lambs with the crosses between Balami rams and Yankasa ewes recording a distinct birth weight of 3.5±0.08 kg while the crosses obtained using Yankasa rams on Uda and Balami ewes gave the lowest birth weights (1.7±0.19 and 1.4±0.18, respectively). Sex and litter type have no significant effect (P>0.05) on gestation length. Birth weight was however affected by sex of lambs and their litter type. Litter type was negatively correlated with birth weight (-0.372). Gestation length had a low and non-significant relationship with birth weight; litter type and lamb genotype. Lamb genotype does not have a significant relationship with litter type. Genetic improvement of Nigeria sheep breed is possible if the resources of within and between breed is exploited. Selection for a reduction in gestation length may indirectly increase prolificacy. (Animal Production 12(3): 135-138 (2010)Key Words : gestation length, birth weight, Nigerian Shee

Evaluation de la diversité agromorphologique des descendances hybrides de cocotier (Cocos nucifera L.) Nain Jaune Malaisie x Grand Vanuatu en Côte d’Ivoire

Ce travail vise à évaluer la diversité agromorphologique des descendances hybrides de cocotier Nain Jaune Malaisie x Grand Vanuatu tolérants à la maladie du jaunissement. Les observations ont porté sur 30 descripteurs liés aux stipes, feuilles, inflorescences et fruits. Les résultats montrent que 12 descripteurs permettent de discriminer les individus au niveau inter et intra-descendance. La structuration de ces descendances a révélé deux groupes. Il s’agit des descendances d15 qui se sont distinguées des autres. Les arbres de la descendance d15 sont caractérisés par une Circonférence du stipe à 20 cm du sol (134,52 cm), un Epaisseur de Pétiole (3,25 cm), une Largeur de Foliole (6,42 cm), un Nombre d’Epillets (40), un Nombre d’Epillet Sans Fleur femelle (23), un Diamètre polaire de la noix (20,03 cm) et une masse de la bourre (291,82 g) supérieures à ceux des autres descendances. Le Géniteur G15 qui donne des descendances robustes et présentant des aptitudes favorables à une bonne production est à sélectionner pour produire des hybrides NJM x GVT tolérants et haut producteurs.Mots clés: Cocotier, hybride, jaunissement mortel, diversité agromorphologique

Macronutrient composition of three cucurbit species cultivated for seed consumption in Côte d’Ivoire

Dry seeds from three indigenous cucurbits [Citrullus lanatus var. citroides (Thumb.) Matsum. & Nakai.,Cucumeropsis mannii Naudin, and Cucumis melo var. agrestis L.] largely cultivated in Côte d’Ivoire andconsumed as sauce thickeners were analyzed for their proximate composition and compared to a locallandrace of peanut (Arachis hypogae L.). The protein contents were 29.23±1.74, 36±2.17, 29.55±2.09, and24.79±0.44% for C. lanatus, C. mannii, C. melo, and A. hypogaea, respectively. The highest estimates offat content was observed with C. lanatus (56.67±4.90%) followed in decreased order by the peanut(48.17±1.60%), C. mannii (45.89±4.73%), and C. melo (42.67±3.43%). The carbohydrate content for C.lanatus was 9.87±3.52% and C. mannii and C. melo had 13.86±3.64 and 23.18±4.80%, respectively. C.melo was then the highest in carbohydrate content whereas A. hypogaea has the lowest value(6.39±2.66%). The crude fibre contents for C. lanatus, C. mannii, and C. melo averaged 2.87±1.07,2.30±0.85, and 2.94±0.75%, respectively. The three cucurbit species were markedly low in fibre value,compared to the analyzed peanut (17.14±3.82%). As expected on the basis of several published data,ash content of seeds from indigenous cucurbits was generally low: 1.33±0.52% (C. lanatus), 2.50±1.38%(C. mannii), and 1.67±0.82% (C. melo)

Relationship Between Gestation Length and Birth Weight in Nigerian Sheep and Their Crosses

Effect of genotype and birth weight on gestation length was evaluated using Nigerian breeds of sheep and their crosses. The study was carried out at the Sheep Project Unit of Small Ruminant Research Programme (SRRP) of National Animal Production Research Institute (NAPRI), Ahmadu Bello University, Shika-Zaria. The sheep breeds used were Balami, Uda and Yankasa. Heat (estrus) detection was carried out twice daily; in the morning (07:00-08:00 hours); and in the evening (16:00-17:00 hours) using apron fitted rams to pick does on heat. A total of 56 lambs were used for this study. The data obtained were subjected to analysis of variance using General Linear Model and Correlation Procedure of SAS. All the genotypes had similar gestation length with values between 150.3±0.61 days and 153.3±0.60 days, except for Balami pure breed (BAL X BAL) lambs that recorded a shorter gestation length (137.1±0.81 days). There was a wide variation in the birth weight of lambs with the crosses between Balami rams and Yankasa ewes recording a distinct birth weight of 3.5±0.08 kg while the crosses obtained using Yankasa rams on Uda and Balami ewes gave the lowest birth weights (1.7±0.19 and 1.4±0.18, respectively). Sex and litter type have no significant effect (P>0.05) on gestation length. Birth weight was however affected by sex of lambs and their litter type. Litter type was negatively correlated with birth weight (-0.372). Gestation length had a low and non-significant relationship with birth weight; litter type and lamb genotype. Lamb genotype does not have a significant relationship with litter type. Genetic improvement of Nigeria sheep breed is possible if the resources of within and between breed is exploited. Selection for a reduction in gestation length may indirectly increase prolificacy. (Animal Production 12(3): 135-138 (2010

Phenomenology of event shapes at hadron colliders

We present results for matched distributions of a range of dijet event shapes at hadron colliders, combining next-to-leading logarithmic (NLL) accuracy in the resummation exponent, next-to-next-to leading logarithmic (NNLL) accuracy in its expansion and next-to-leading order (NLO) accuracy in a pure alpha_s expansion. This is the first time that such a matching has been carried out for hadronic final-state observables at hadron colliders. We compare our results to Monte Carlo predictions, with and without matching to multi-parton tree-level fixed-order calculations. These studies suggest that hadron-collider event shapes have significant scope for constraining both perturbative and non-perturbative aspects of hadron-collider QCD. The differences between various calculational methods also highlight the limits of relying on simultaneous variations of renormalisation and factorisation scale in making reliable estimates of uncertainties in QCD predictions. We also discuss the sensitivity of event shapes to the topology of multi-jet events, which are expected to appear in many New Physics scenarios.Comment: 70 pages, 25 figures, additional material available from http://www.lpthe.jussieu.fr/~salam/pp-event-shapes