122418 research outputs found
Sort by
Technical Support Mission to OLAM coffee plantations in Lao PDR : 28th January to 7th February 2013
No full textA visit of the four farms was made with the managers in charge. The report describes the observations on state of the four farms thanks to the information given by the managers and supervisors. Recommendations are made to improve some points, which relate to: - Improved weed control. The use of shade and legumes cover crop is suggested. - Some explanations about pruning techniques to justify the needed change. - A fertilization program for the coming years. In all farms, the percentage of weak coffee plants is very high, and it seems to be a consequence of planting with bent rooted seedlings. The state of the coffee production is quite low considering the age of coffee (4-years-old). Therefore, it is important that Olam manages its own nurseries. Two of the farms (Thevada and Khongtoun) are well located and in a very favourable area for growing quality Arabica coffee trees. On the other hand, the other two farms (Xekatam and Xepian) are in a drier area and coffee is grown on quite poor soils, mainly because the previous crops consisted of grasses and reeds. In both these farms, the soil nutrient levels are below the acceptable thresholds for coffee. There is need to drastically increase the organic matter and use of leguminous shade trees. In these farms, the use of irrigation is also strongly suggested to compensate for lack of rainfall. The last day, a summary of the observations and recommendations was reported to the director and all the staff
Amélioration de l'après récolte et valorisation du fonio en Afrique (Aval Fonio) : Rapport de l'atelier des WP l à 4 9-13 juin 2014 Bamako-Mali
No full textIntegrated natural resources management at meso scale: a process oriented approach to craft operational strategies for adaptation and vulnerability reduction to global change: AFROMAISON. Deliverable7.1
No full textL'utilisation de l'autocorrélation spatiale pour l'identification de zones à risque épidémiologique et socio-économique en santé animale : a case study on contagious bovine pleuropneumonia (CBPP) and cattle mobility in the Ethiopian highlands
No full textLa délimitation de structures géographiques intervenant dans les processus spatio-temporels de transmission des maladies animales contagieuses, constitue un enjeu fondamental pour la planification de programmes de contrôle adaptés. L'auteur propose une approche de géographie de la santé animale, appliquée à la régionalisation des risques. Elle est basée sur l'analyse spatiale du système territorial, et sur l'étude de l'autocorrélation spatiale locale. L'analyse est illustrée par une recherche sur la Péripneumonie contagieuse bovine et la mobilité de l'élevage, dans une petite région d'Ethiopie. Elle révèle la capacité des méthodes d'analyse à y rendre compte de plusieurs dimensions socio-économiques et épidémiologiques du risque. La constitution finale d'un portefeuille de cartes se révèle adaptée pour guider la décision sanitair
Troisième rapport annuel STD3 germplasm-hévéa. Contrat n. TS3*-CT92-0133. Etude et caractérisation de nouvelles ressources génétiques : leur utilisation en amélioration de l'hévéa, décembre 1994 - décembre 1995
No full textLa prospection flance-brésilienne de 1974 et la prospection internationale organisée par l'IRRDB en 1981, concernant l'espèce Hevea brasiliensis en forêt amazonienne, et l'introduction de ce matériel végétal, ainsi que d'un échantillonnage des prospections réalisées par Schultes en Colombie, sont à l'origine du développement d'un important projet relatif aux ressources génétiques de cet arbre. Ce projet, soutenu financièrement par l'Union Européenne, associe en partenariat l'IDEFOR-DPL en Côte d'Ivoire, l'IRA au Cameroun, le CIRAD à Montpellier et en Guyane et l'Université Catholique de Louvain-la-Neuve en Belgique. Ce rapport est celui de la troisième année d'exécution du projet (contrat n. TS3-CT92-0133) qui s'achèvera le 30 novembre 1996 et sera conclu par un rapport scientifique final. Les résultats obtenus par les différentes équipes au cours de l'année 1995 sont présentés dans ce documen
Deep-fat frying of cassava : influence of raw material properties on chip quality
No full textThirteen cultivars of cassava (Manihot esculenta Crantz) were used to obtain chips by deep frying slices of fresh cassava flesh in palm oil. The cultivars were representative of three different levels of four major characteristics (water, cyanide, starch and amylose content) in parenchyma. The effects of raw material composition and crop age (10 and 12 months) on mass transfer (dehydration and oil uptake), texture and colour were assessed for 1.5mm thick chips with a final water content of 0.04kg kg -¹ wet basis, corresponding to a water activity of about 0.3. Frying time varied from 70 to 90s and oil bath temperature from 140 to 160°C. All cultivars gave a high frying yield (>0.5 kg chips Kg-¹ fresh cassava) and a chip fat content of between 0.23 and 0.37 kg kg -¹ wet basis, with the highest frying yields and lowest fat contents being obtained from roots with the lowest water content and cyanide content. The intensity of darkening reactions increased in accordance with the level of reducing sugars, while the rigidity modulus of the chips was negatively correlated with the fibre content. The other characteristics (starch, amylose and total sugar content) were either not or poorly correlated with any of the chip quality parameters studied. Cyanoglucosides were only partially eliminated during frying (over 40% retention), so cultivars with a high cyanide content gave bitter chips. For a similar composition, drying rates and cooking rates were much lower when crop age increased. This could be attributed to a structural effect characterising crop age
Is acetyl/butyrylcholine specificity a marker for insecticide-resistance mutations in insect acetylcholinesterase ?
No full textSubstrate specificity has been widely studied in vertebrate cholinesterases and it has been shown that two phenylalanines in the acyl pocket of acetylcholinesterase govern the acceptance of the acetyl/butyryl moiety of the choline esters. As an insecticide-resistance mutation has been evidenced in the acyl pocket of Drosophila melanogaster and Musca domestica acetylcholinesterase we investigated the possibility of linking changes in acetyl/butyrylthiocholine specificity with mutations in insect acetylcholinesterase. We thus analyzed the effect of 28 mutations in Drosophila enzyme on acetyl/butyrylthiocholine, N-methyl/N-propyl-carbamates and ethyl/methyl-paraoxon preference. It appeared that the highest changes on acetyl/butyrylthiocholine and N-propyl/N-methyl-carbamates preference were due to mutations in the acyl pocket. Nevertheless, other insecticide-resistance mutations, not located in the acyl pocket, also modified these substrate preferences. Moreover, the effect of mutations in the acyl pocket was hidden when some other insecticide-resistance mutations were combined in the enzyme. Consequently, acetyl/butyrylthiocholine preference alteration cannot be used as a marker to localize a mutation in the insect AChE
Seasonal abundance of mango fruit flies (Diptera: tephritidae) and ecological implications for their management in mango and cashew orchards in Benin (centre and north)
No full textWe report the results of a large-scale (six orchards) and long-term (5-yr) study on seasonal population fluctuations of fruit flies (Diptera Tephritidae) in mango (2005–2009) and cashew (2007–2009) orchards in the Borgou Department, Benin. During the five consecutive years of mango fruit fly monitoring, 25 tephritid species were captured including three species of Bactrocera, 11 of Ceratitis, and 11 of Dacus, which is represented by 2,138,150 specimens in mango orchards. We observed significant differences in Bactrocera dorsalis (Hendel) counts between “high” and “low” mango production years from 2005 to 2008 but not in Ceratitis cosyra (Walker) counts. The native species, C. cosyra, the most abundant species during the dry season, peaked beginning of May, while the exotic species, B. dorsalis, the most abundant species during the rainy season, peaked in June. Preliminary results underlined the role of nine species of wild hosts and seven species of cultivated ones around mango orchards that played an important role in maintaining B. dorsalis in this Sudan zone all year round. The presence of C. cosyra stretched over 9 mo. During the first 14 wk of tephritid monitoring on cashew orchards situated near mango orchards, most flies (62%) were captured in traps positioned in cashew orchards, showing the strong interest of an early fly control on cashew before the mango season. According to these results, in the Sudan zone, effective and compatible control methods as proposed by the IPM package validated by the West African Fruit Fly Initiative project against mango fruit flies are proposed for a large regional tephritid control program in same zones of West Africa
Somaclonal variants of taro (Colocasia esculenta Schott) and yam (Dioscorea alata L.) are incorporated into farmers' varietal portfolios in Vanuatu
No full textTaro (Colocasia esculenta) and the greater yam (Dioscorea alata) are staples in Vanuatu. The aim of the present study was to assess the role of somaclonal variations in the varietal diversification of these two clonally propagated crops. The study was conducted in six villages located each on distinct islands of Vanuatu, Melanesia. Overall, 203 varieties of taro and 80 varieties of yam were collected and DArTs were used for analysis. The overall quality of the DArT markers was high for both species. The percentage of polymorphic clones detected on the DArT array was low for taro (3 %) and high (13 %) for yam, with respectively 202 and 499 polymorphic clones. Each variety was characterized by its multilocus genotype based on its DArT presence/absence profile. For taro, the 203 varieties were represented by 126 unique genotypes and 34 distinct multilocus lineages (MLLs). The high number of unique genotypes and the presence of few varieties sharing a clonal origin, generated a high varietal richness index (R = 0.83). For yam, the 80 varieties were represented by seven unique genotypes and 16 MLLs. The low number of unique genotypes and the presence of numerous varieties sharing a clonal origin generated a low varietal richness index (R = 0.26). Possible factors contributing to these contrasting results are discussed. DArT markers provide evidence that somaclonal variants of taro and yam are selected as new varieties. Strategies aiming at strengthening communities' capacity to adapt to forthcoming changes should consider the introduction of allelic diversity into farmers' varietal portfolios