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See detailAttempted cultivation of Jatropha curcas L. in the lower Senegal river valley: story of a failure
Terren, Marieke ULg; Saverys; Jacquet de Haveskercke, Paul et al

in Tropicultura (2012), 30(4), 204-208

With the objective of determining whether it would be possible to sustainably produce Jatropha curcas L. seeds on the marginal land situated close to the Senegal River, a 6-hectare pilot plantation was ... [more ▼]

With the objective of determining whether it would be possible to sustainably produce Jatropha curcas L. seeds on the marginal land situated close to the Senegal River, a 6-hectare pilot plantation was cultivated under drip irrigation between September 2007-November 2011, close to the village of Bokhol (Lat. 16°31’N, Long. 15°23’W). A series of tests were conducted on this plot, in order to identify the best cultivation methods for the area (date, density and method of planting, appropriate type of pruning, fertilisers to be applied, irrigation method, etc.). The average yields obtained at this site, after four years of cultivation (less than 500 kg.ha-1 of dry seed), using the best known production techniques, are significantly lower than anticipated, compared to the available figures for the irrigated cultivation of Jatropha in other parts of the world. The main causes of this failure are the plant’s limited useful vegetation period of six months per year, instead of twelve, and the scale of attacks by a soilborne vascular disease, which destroyed over 60% of the plantation within four years. [less ▲]

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See detailPrincipal disease and Insect pests of Jatropha curcas L. in the lower valley of the Senegal river
Terren, Marieke ULg; Mignon, Jacques ULg; De Clerck, Caroline ULg et al

in Tropicultura (2012), 30(4), 222-229

Jatropha curcas L. seed oil is proven to be toxic to many microorganisms, insects and animals. Despite its toxicity, Jatropha is not pest and disease resistant. The following major pests and diseases ... [more ▼]

Jatropha curcas L. seed oil is proven to be toxic to many microorganisms, insects and animals. Despite its toxicity, Jatropha is not pest and disease resistant. The following major pests and diseases affecting Jatropha in the lower valley of the Senegal river have been identified: the leaf miner Stomphastis thraustica (Meyrick, 1908) (Lepidoptera, Gracillariidae), the leaf and stem miner Pempelia morosalis (Saalmuller, 1880) (Lepidoptera, Pyralidae) and the shield-backed bug Calidea panaethiopica (Kirkaldy, 1909) (Heteroptera, Scutelleridae), which can cause flower and fruit abortion. Damage from these pests was particularly great during the second year after the plantations were set up (2009) and before later receding. Nevertheless, the worst attacks were caused by a vascular disease transmitted through the soil, which killed 65% of the plants in four years. It is mainly characterised by collar and root rot, which causes foliage to yellow and wilt, before the plant eventually dies. These threats should increase if larger areas are planted with Jatropha. Considering the scale of the damage caused by these attacks in Bokhol, the development of an integrated pest management programme adapted to the local context should be considered. [less ▲]

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See detailIntérêts de mettre en place une filière courte basée sur la culture du jatropha (Jatropha curcas L.) dans la communauté rurale de Dialacoto
Barbier, Jérémy; Cissao, Malang; Tacourou, Bocar et al

Report (2012)

Opportunities to develop a local chain of production, transformation, and marketing based on jatropha cultivation were investigated from 2008 to 2012 in the rural community of Dialacoto (Tambacouda Region ... [more ▼]

Opportunities to develop a local chain of production, transformation, and marketing based on jatropha cultivation were investigated from 2008 to 2012 in the rural community of Dialacoto (Tambacouda Region, Eastern Senegal). The researches have mainly concerned how to integrate jatropha cultivation in existing cropping systems, the modalities to process the seeds with a manual Bielenberg press, and the opportunities for a local transformation and marketing of oil and oilcakes obtained by pressing seeds. The ways to integrate the cultivation of jatropha in the traditional farming systems were studied using two participatory investigation methods and by carrying out agronomic trials on experimental plots. An action research was conducted with three groups of six farmers in order to determine the best modalities of installation and maintenance of jatropha plants. The fields of 24 farmers where jatropha plants were installed as a sole crop, intercropped with cultivated annual plants, or as a living hedge were closely monitored. These fields were selected among the 295 plots that had been planted before or at the beginning of the project. Under the current conditions of remuneration of jatropha seeds in Senegal (65 Fcfa / 0,1 EUR kg-1 dry seeds), and given the low seed yield (less than 200 kg ha-1 for the best tended plots after five years) and the low precocity of the available planting material, the sole and the intercropping of jatropha is not profitable. The development of efficient intercropping systems adapted to the farmer's constraints seems possible, subject to the selection of varieties of jatropha both early and productive, and to an increase in the purchase price of the seeds. Substantial research involving directly the farmers remains to be carried out to develop these intercropping systems. The establishment of living hedges is for the moment the only installation method that can be recommended to farmers. In addition to providing supplementary income related to seed harvest, hedgerows provide different benefits appreciated by farmers: land demarcation, soil protection against wind and water erosion, improved soil water balance and windbreak effect favorable to crop development, crop protection against wandering ruminants, and enclosure for the cattle. These various benefits and the low risk taken by installing hedgerows explain that this method of planting was the most often selected spontaneously by farmers. The production cost of a liter of jatropha filtered oil using a Bielenberg press rises to 1056 FCFA (1.62 EUR). At such a cost, jatropha oil is not competitive compared to its direct use for diesel engines in rustic Lister type used to operate multifunctional platforms. The production of soap is the only local outlet with high potential for oil produced with a manual press. The price of locally produced soap with this oil is competitive compared to that of the industrial soap available on the market and its quality is highly appreciated by potential customers. The use of oil as a bio-pesticide and as fuel for lighting could be interesting opportunities but further investigations are needed to confirm this. This applies also to the use as fertilizer of the oilcakes produced by pressing seeds. [less ▲]

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See detailScaphandre La science rencontre l'art: L'alimentation
Haubruge, Eric ULg; Bay, Daniel ULg; Semal, Jean et al

in Haubruge, Eric; Bay, Daniel; Semal, Jean (Eds.) Scaphandre La science rencontre l'art (2012)

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See detaileffets de la substitution totale du tourteau d’arachide par la fève de coton glandless sur les performances zootechniques de poulets de chair au sénégal
Diaw, Mamadou; Dieng, Abdoulaye; Mergeai, Guy ULg et al

in Revue d'Elévage et de Médecine Vétérinaire des Pays Tropicaux (2012), 65(1-2), 17-23

The performances of broilers fed a diet in which the groundnut cake was totally replaced by glandless cottonseed kernels (FCG) were compared to those of animals fed an experimental control diet (Tém_E), a ... [more ▼]

The performances of broilers fed a diet in which the groundnut cake was totally replaced by glandless cottonseed kernels (FCG) were compared to those of animals fed an experimental control diet (Tém_E), a commercial diet (Tém_C), and a very simple diet containing only corn, FCG and a mineral and vitamin concentrate. From the start, the Tém_C and FCG animals showed the highest growths. After 43 days of breeding, there were major differences in body weights between the groups, essentially caused by differences in feed intake, so that the best growth rates were not necessarily linked to better feed conversion ratios. Low body weights, low intakes and high mortality levels were observed with the simple diet. [less ▲]

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See detailStudy of agronomic constraints to the dissemination of the cultivation of Jatropha curcas L. in Senegal
Terren, Marieke ULg; Saverys, S.; JACQUET DE HAVESKERCKE1, P. et al

Poster (2012)

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See detailAlien chromosome transmission and somatic elimination in monosomic addition lines of Gossypium australe F. Muell in G. hirsutum L
Sarr, Djibril; Lacape, Jean-Marc; Jacquemin, Jean-Marie et al

in Euphytica : International Journal of Plant Breeding (2012), 183

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See detailIn vitro culture of Jatropha curcas L (Culture in vitro de Jatropha curcas L.)
Medza Mve, S.D.; Mergeai, Guy ULg; Baudoin, Jean-Pierre ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2011), 15(4), 567-574

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See detailEvaluation agromorphologique et sélection des meilleures accessions de Pourghère (Jatropha curcas L.) introduites au Bénin
Ahoton, L. E.; Quenum, F.; Mergeai, Guy ULg

in International Journal of Biological and Chemical Sciences (2011), 5(4), 1619-1627

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See detailLes co-produits de la graine de coton en alimentation du poulet de chair
Diaw, Mahamadou Tandiang; Dieng, Abdoulaye; Mergeai, Guy ULg et al

in Annales de Médecine Vétérinaire (2011), 155

Cottonseed by-products arevery high in nutrients and theirchemical composition varieshighly according to the varietiesof cotton and the various treatmentsaiming at extracting oil.Their use in animal ... [more ▼]

Cottonseed by-products arevery high in nutrients and theirchemical composition varieshighly according to the varietiesof cotton and the various treatmentsaiming at extracting oil.Their use in animal nutrition, andparticularly in broilers, is especiallylimited by the free gossypolwhich can damage varioustissues and also decreases theperformances of growth and dietefficiency. The incorporation ofcottonseed meal in broilers dietmay be increased following chemicalbinding of free gossypol,but these methods have drawbacks.Ferrous sulfate denaturesfeed and the use of lysine to bindgossypol is limited by the expensivenessof this product while thebiological fermentation is verycomplex and inapplicable, as tonow, on a large way. Glandlessvarieties could be incorporatedat a very high level in diets andtherefore could contribute todecrease the protein feed requirements.Unfortunately, agronomicconstraints associated to thesecrops have limited the research inthis way. The production of varietiesin which gossypol secretionwould be inhibited before theseed germination should alleviatethe limitations associated to cottonby-products. [less ▲]

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See detailJATROPHA CURCAS IN SUB-SAHARAN AFRICA: THE BIG ILLUSION?
Mergeai, Guy ULg; Terren, Marieke ULg; Jacquet de Haveskercke, P. et al

Conference (2011)

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See detailInsecticidal effect of Jatropha curcas oil on the aphid Aphis fabae (Hemiptera: Aphididae) and on the main insect pests associated with cowpeas (Vigna unguiculata) in Niger
Abdoul Habou, Zakari; Haougui, A.; Mergeai, Guy ULg et al

in Tropicultura (2011), 29(4), 225-229

The insecticidal activity of Jatropha curcas has been evaluated on various crop pests. Oil concentrations of 0.5, 1, 2.5, 5, 10 and 15% were first tested on the black bean aphid (Aphis fabae Scop.) as ... [more ▼]

The insecticidal activity of Jatropha curcas has been evaluated on various crop pests. Oil concentrations of 0.5, 1, 2.5, 5, 10 and 15% were first tested on the black bean aphid (Aphis fabae Scop.) as part of an efficacy test conducted in the laboratory. During a second stage, the insecticidal efficacy of 5 and 7.5% oil concentrations was evaluated on the main pests infesting cowpea crops (Vigna unguiculata L.) as part of a field test conducted at the University of Niamey (Niger). The results obtained in the two tests demonstrate the biocidal effect of the treatments applied, which increases with the concentration. On the black bean aphid, the biocidal effect increases during the hours following the application of oil before reaching a peak after 4 days. On cowpeas, J. curcas oil concentrations of 5% and 7.5% make it possible to reduce the level of attack by aphids (Aphis craccivora) by 10 and 50% respectively compared to the control. A 50% and 75% fall in the number of thrips (Megalurothrips sjöstedti) and bugs (Anoplocnemis curvipes), respectively, can be observed under the same conditions. This treatment made it possible to greatly increase yields compared to the untreated control. [less ▲]

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See detailIsolation of five new monosomic alien addition lines of Gossypium australe F. Muell in G. hirsutum L. by SSR and GISH analyses
Sarr, D.; Lacape, J.-M.; Rodier-Goud, M. et al

in Plant Breeding (2010), 130

Gossypium australe F. Muell (2n + 2x = 26) is a wild perennial species possessing agronomic useful traits that would be interesting to introgress into G. hirsutum L. (2n = 4x = 52), the main cultivated ... [more ▼]

Gossypium australe F. Muell (2n + 2x = 26) is a wild perennial species possessing agronomic useful traits that would be interesting to introgress into G. hirsutum L. (2n = 4x = 52), the main cultivated cotton species. To isolate monosomic alien addition lines (MAALs) of G. australe in G. hirsutum, the [2(G. hirsutum X G. australe) X G. hirsutum] pentaploid (2n = 5x = 65) was backcrossed as male parent to G. hirsutum. Analysis of 42 BC1 plants and seven alien addition lines, already available, with 150 SSR markers developed from G. hirsutum revealed a cross-species amplification rate of 100% and a polymorphism rate of 56%. Eighty polymorphic SSR markers generated 87 G. australe-specific loci that have been assigned by a hierarchical cluster analysis to 13 linkage groups corresponding to the 13 chromosomes of G. australe. Analysis by SSR markers and genomic in situ hybridization of the self-progeny of disomic alien addition lines, backcross progeny of the pentaploid, allowed the isolation of five new MAALs. [less ▲]

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See detailEffect of GammaRay in the Progeny of Trispecific Hybrid [(Gossypium hirsutum x G. raimondii)² x G. sturtianum]
Diouf, Fatimata Bintou Hassédine ULg; Benbouza, H; Konan, O et al

in Notulae Botanicae Horti Agrobotanici Cluj-Napoca (2010), 38

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See detailDevelopment of Upland Cotton Plants Highly Resistant to the Reniform Nematode From the G. Hirsutum x G. Thurberi x G. Longicalyx Hybrid
Mergeai, Guy ULg; Konan, N.O; Baudoin, Jean-Pierre ULg

in Proceedings of the beltwide cotton improvement conference (2010)

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See detailAmélioration du taux de multiplication in vitro de Jatropha curcas L.
Medza Mve, S. D.; Mergeai, Guy ULg; Baudoin, Jean-Pierre ULg et al

in Tropicultura (2010), 28(4), 200-204

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See detailEffect of Groundnut Cake Substitution by Glandless Cottonseed Kernels on Broilers Production: Animal Performance, Nutrient Digestibility, Carcass Characteristics and Fatty Acid Composition of Muscle and Fat
Diaw, Mamadou Tandiang; Dieng, Abdoulaye; Mergeai, Guy ULg et al

in International Journal of Poultry Sciences (2010), 9(5), 473-481

A study has been conducted with broilers to assess, during the rainy season, the effects of groundnut cake substitution by glandless Cottonseed Kernel (CSK), at levels of 0, 25, 50 and 75%. The ... [more ▼]

A study has been conducted with broilers to assess, during the rainy season, the effects of groundnut cake substitution by glandless Cottonseed Kernel (CSK), at levels of 0, 25, 50 and 75%. The substitution improved linearly feed intake and animal growth, as well as carcass component weights and allometric parameters. The CSK increased the C18:2 n-6 to C18:1 n-9 ratio, as well in diet as in meat and subcutaneous fat. In order to explain the observed performances, the possibility is considered that broilers used preferentially C18:2 n-6 fatty acids for their metabolism. Complete glandless cottonseed kernels are probably highly valuable for broilers production in warm and wet conditions. [less ▲]

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See detailEffets de la substitution du tourteau d’arachide par la fève de coton conventionnel en production de poulet de chair au Sénégal
Diaw, Mamadou Tandiang; Dieng, Abdoulaye; Mergeai, Guy ULg et al

in Tropicultura (2010), 28(3), 139-147

A study has been conducted on 400 chicks to evaluate conventional cottonseed kernels on broilers production. Groundnut cake has been substituted by cottonseed kernels at 0, 25, 50 and 75% levels ... [more ▼]

A study has been conducted on 400 chicks to evaluate conventional cottonseed kernels on broilers production. Groundnut cake has been substituted by cottonseed kernels at 0, 25, 50 and 75% levels. Cottonseed kernel incorporation decreased significantly (p< 0.001) the growing parameters, feed intake, feed efficiency and nutrients digestibility of the experimental diets. This reduction was proportional to the level of substitution. The study suggests that only the level of gossypol in cottonseed kernels limits their incorporation in broilers diets and that this by-product should be excluded from the formulation in broilers production or that its level of incorporation should be limited to a maximal level of 10% when production duration is not a constraint for breeders. [less ▲]

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