273 research outputs found
Study of the Root System of Local and Improved Sorghum Cultivars Grown in Mali
Roots play a fundamental role in plant growth by supplying water and mineral to the stem and
leaves. These underground organs are much less known than the aerial organs mainly due to the
difficult access to the root systems in soil. In spite of this, only a few studies were conducted on
roots. Given the importance of roots for plant growth, a better understanding of their functioning
may help solve some issues such as water stress that can affect the performance of the crops. A
total of 100 sorghum cultivars collected in the Sahelian zone of Mali an area receiving an annual
rainfall of 200 to 600 mm, were used in a root characterization study. The plant materials were
composed of 4 races and 5 intermediates sorghum races. Seeds of the entries were planted
directly in PVC tubes of 1m containing soil and arranged in completely randomized design with
three replications; in one planting date. Each tube was planted in a dugout ground to 50 cm deep.
The tubes were distant of 0.50 m within each row and 0.75 m between rows. The trial was watered
from the tap every two days until harvest. The results showed high variability among the varieties
studied for root length and root density, with a root length reaching over 1.00m. The study did not
identify any pattern in the root systems of the four races and their five intermediates races.
However, there was a positive correlation between root length and density indicating an increase in
root length correspond to an increased root density. The diversity found in the root system could be
a basis for improving root architecture in breeding populations and the evaluation of the behaviour
of the sorghum varieties with different root systems in water stress conditions
Efficacite de lâhydroxyde de cuivre contre la nervation noire du chou (Brassica oleracea l.) Causee par la bacterie xanthomonas campestris pv. Campestris
Pour tester lâefficacitĂ© de lâhydroxyde de cuivre contre la nervation noire du chou, des expĂ©rimentations ont Ă©tĂ© conduites sur le site maraĂźcher de HouĂšto (commune dâAbomey-Calavi), au cours desgrande et petite saisons de pluies de lâannĂ©e 2013. Le dispositif de bloc alĂ©atoire complet dispersĂ© Ă quatre rĂ©pĂ©titions et cinq traitements a Ă©tĂ© utilisĂ©. Les parcelles tĂ©moins, traitĂ©es avec lâoxyde de cuivre 1 kg/ha et avec lâhydroxyde de cuivre aux doses de 2,25 kg/ha, 3 kg/ha et 4,5 kg/ha Ă©taient les traitements Ă comparer. La sensibilitĂ© de Xanthomonas campestris pv. campestris (Xcc) Ă lâhydroxyde de cuivre, lâincidence et la sĂ©vĂ©ritĂ© de la nervation noire du chou Ă©taient les paramĂštres Ă©valuĂ©s au cours des expĂ©rimentations. La bactĂ©rie Xcc a Ă©tĂ© positivement confirmĂ©e. Pendant la grande saison de pluies, la sĂ©vĂ©ritĂ© a Ă©tĂ© significativement faible dans les parcelles traitĂ©es avec lâhydroxyde de cuivre aux doses de 3 kg/ha (7,11 %) et 4,5 kg/ha (7,09 %). Par contre, en petite saison de pluies, la maladie sâĂ©tait faiblement manifestĂ©e sur tout le site expĂ©rimental avec une sĂ©vĂ©ritĂ© infĂ©rieure Ă 0,05 %. Lâincidence Ă©tait aussi plus Ă©levĂ©e au cours de la grande saison de pluies (79,6 % Ă 82,5 %) comparĂ©e Ă la petite saison de pluies (0,9 % Ă 1,6 %). Les doses de 3 kg/ha et 4,5 kg/ha dâhydroxyde de cuivre ont Ă©tĂ© les plus efficaces contre la nervation noire du chou.Mots clĂ©s : Nervation noire du chou, hydroxyde de cuivre, efficacitĂ©, Xanthomonas campestris pv. campestrisEnglish abstractEfficiency of copper hydroxide on cabbage (Brassica oleracea l.) Black rot caused by xanthomonas campestris pv. CampestrisTo test the efficiency of copper hydroxide against the cabbage black rot, trials were conducted on the garden site of Houeto village (Abomey-Calavi), during the big and the short rainy seasons in 2013. The randomized complete block design with four repetitions and five treatments have been used. Untreated control plot, plot treated with copper oxide at 1 kg/ha and plots treated with copper hydroxide at 2.25 kg/ha, 3 kg/ha and 4.5 kg/ha were the five considered treatments. The susceptibility of Xanthomonas campestris pv. campestris (Xcc) to the copper hydroxide, the incidence and the severity of cabbage black rot, were the evaluated parameters during the two trials. Xcc was positively confirmed. During the big rainy season, the severity was significantly low in plots treated with copper hydroxide at 3 kg/ha (7.11 %) and 4.5 kg/ha (7.09 %). While during the short rainy season, the disease was weak in the whole experimental site with a severity varying between 0.02 % and 0.03 %. The incidence was also high during the big rainy season (79.6 % to 82.5 %) and weak during to the short rainy season (0.9 % to 1.6 %). The doses of 3 kg/ha and 4.5 kg/ha of copper hydroxide were efficient on cabbage black rot.Key words : Cabbage black rot, copper hydroxide, efficiency, Xanthomonas campestris pv. campestri
Development and Utilisation of Improved WhiteSeeded, Tan-Plant Grain Sorghum Cultivars in Mali
The pedigree breeding method was successfully adopted to develop high yielding, white-seeded, grain sorghum cultivars with other attributes including âtanâ plants, sensitivity to photoperiod and excellent adaptation to the Sudanian and Sahelian agro-ecological conditions in Mali. The new cultivars possess an excellent grain quality which added value for processing. The breeding process included crossing of local guinea race cultivars and improved or introduced Caudatum race varieties, selected from F2, F3, F4, F5 and F6 generations, conducting yield and grain quality trials of advanced lines on station and on-farm with farmer participatory selection. Processing quality of the grain was evaluated through measuring the decortication yield of each cultivar using the TADD (Tangential Abrasive Dehuller Device); measuring shelf life of processed flour in bags made of polyethylene for 3 months; manufacturing of new products by partially substituting wheat flour with flour of new sorghum varieties in pastry and biscuits. The study revealed a series of improved lines with "tan" plants, white grain, Guinea race type characterised by a loose panicle, long glumes and a hard grain. The best example of new cultivars NâTenimissa, was described as the first white, âtanâ plant, straw-coloured glume, photoperiod sensitive and high yielding sorghum cultivar with a white endosperm, and a thin pericarp developed in Mali. The cultivar has almost the same decortication yield with already adopted varieties by farmers. Its flour yield is similar to that of local guinea cultivars, and its flour is nearly as white as wheat flour. The analysis of various organoleptic parameters indicated that partially substituting wheat with 20% sorghum flour made the preferred biscuit by consumers prompting the commercial manufacturing of a biscuit called Deliken by the General Alimentation du Mali (GAM). A commercial sorghum supply chain was initiated by linking smallholders producing the new cultivar to a grain trader for selling the grain to the industry. This shows a path for the future in the diversification of uses of a local staple crop, sorghum. It is based on a strong Public-Private Partnership to link smallholders to the commercial supply chain, providing an incentive for farmers to grow new and highly productive cultivars for the development of value-added products
Field experiments of Anopheles gambiae attraction to local fruits/seedpods and flowering plants in Mali to optimize strategies for malaria vector control in Africa using attractive toxic sugar bait methods
<p>Abstract</p> <p>Background</p> <p>Based on recent studies in Israel demonstrating that attractive toxic sugar bait (ATSB) methods can be used to decimate local anopheline and culicine mosquito populations, an important consideration is whether the same methods can be adapted and improved to attract and kill malaria vectors in Africa. The ATSB approach uses fruit or flower scent as an attractant, sugar solution as a feeding stimulant, and an oral toxin. The ATSB solutions are either sprayed on vegetation or suspended in simple bait stations, and the mosquitoes ingesting the toxic solutions are killed. As such, this approach targets sugar-feeding female and male mosquitoes. This study examines the attractiveness of African malaria vectors to local fruits/seedpods and flowering plants, key biological elements of the ATSB approach for mosquito control.</p> <p>Methods</p> <p>Three field experiments were conducted at sites in Mali. The attraction of <it>Anopheles gambiae </it>s.l. to 26 different local fruits and seedpods was determined at a site in the semi-arid Bandiagara District of Mali. Wire mesh glue traps with fruits/seedpods suspended on skewers inside were set along a seasonal lagoon. Seven replicates of each fruit/seedpod species were tested, with a water-soaked sponge and a sugar-soaked sponge as controls. The attraction of <it>An. gambiae </it>s.l. to 26 different types of flowering plants was determined at a site near Mopti in Mali. The flowering plants held in a water-filled buried container were tested using the same glue traps, with controls including water only and sugar solution. Six replicates of each selected plant type were tested on transects between rice paddies. Additional studies using CDC light traps were done to determine the relative densities and periodicity of <it>An. gambiae </it>s.l. attraction to branches of the most highly attractive flowering plant, branches without flowers, human odor, and candescent light.</p> <p>Results</p> <p>Of the 26 fruits and seedpods tested, 6 were attractive to <it>An. gambiae </it>s.l. females and males, respectively. Guava (<it>Psidium guajava</it>) and honey melon (<it>Cucumis melo</it>) were the two most attractive fruits for both females and males. Of the 26 flowering plants tested, 9 were significantly attractive for females, and 8 were attractive for males. <it>Acacia macrostachya </it>was the most attractive flowering plant. Periodicity studies using this plant showed peaks of <it>An. gambiae </it>s.l. attraction between 1930 and 2200 h and 0400-0500 h, which differed considerably from the response to human odors, which expectedly peaked at around midnight.</p> <p>Conclusion</p> <p>These field experiments in Mali highlight that female and male <it>An. gambiae </it>s.l. have pronounced differences in attraction for diverse types of indigenous fruits/seedpods and flowering plants. The identification of attractive fruits and seedpods shows that a variety of indigenous and locally abundant natural products could potentially be used as juices to make ATSB solution for mosquito control. As well, the simple methods used to identify the most attractive flowering plants provide valuable insights into the natural history of sugar feeding for <it>An. gambiae </it>s.l. These observations can be used to guide future strategies for employing ATSB methods for malaria vector control in Africa. They also provide a basis for subsequent chemical analysis and development of attractive baits for mosquito control.</p
SĂ©lection participative des variĂ©tĂ©s de sorgho Ă lâaide dâessais multilocaux dans deux zones cibles
Variety development for sorghum requires multi-location testing for yielding ability. In West-Africa, where adaptation to specific zones of rainfall distribution is crucial for the success of a variety, these multi-location trials need to be conducted within any specific zone of adaptation. As most West-African countries lack sufficient research station capacity for this type of yield testing, we have developed a trial design and experiments with a sharing of roles and responsibilities between farmers, NGO's and researchers that allow for effective varietal differentiation in the target environment across a wide range of production conditions within a zone. The added advantage of farmer participation in this early stage of variety evaluation is that farmers also evaluate a wide range of other traits that are essential for making a variety a success
The Schistosomiasis Control Initiative (SCI): rationale, development and implementation from 2002-2008
Schistosomiasis remains one of the most prevalent parasitic diseases in developing countries. After malaria, schistosomiasis is the most important tropical disease in terms of human morbidity with significant economic and public health consequences. Although schistosomiasis has recently attracted increased focus and funding for control, it has been estimated that less than 20% of the funding needed to control the disease in Africa is currently available. In this article the following issues are discussed: the rationale, development and objectives of the Schistosomiasis Control Initiative (SCI)-supported programmes; the management approaches followed to achieve implementation by each country; mapping, monitoring and evaluation activities with quantifiable impact of control programmes; monitoring for any potential drug resistance; and finally exit strategies within each country. The results have demonstrated that morbidity due to schistosomiasis has been reduced by the control programmes. While challenges remain, the case for the control of schistosomiasis has been strengthened by research by SCI teams and the principle that a national programme using âpreventive chemotherapy' can be successfully implemented in sub-Saharan Africa, whenever the resources are available. SCI and partners are now actively striving to raise further funds to expand the coverage of integrated control of neglected tropical diseases (NTDs) in sub-Saharan Afric
Learning from farmers to improve sorghum breeding objectives and adoption in Mali
Many efforts have been made to improve sorghum [Sorghum bicolor (L.) Moench] varieties, but adoption of improved varieties remains low. Sorghum has diverse panicle architecture and grain qualities that vary within and between races, and utilization and adoption may depend on these traits. Recent efforts in West Africa to improve local guinea race germplasm as a base material have diversified potential options: there are breeding materials with a range of panicle types with increased grain number per panicle and a range of droopiness, as well as laxness and threshability. This study was designed to expand our understanding about sorghum grain and panicle traits that are important for farmers in the Sudan savanna zone of Mali. We combined a sorghum panicle sorting activity with qualitative interviews in Mande and DioĂŻla to understand farmersâ knowledge and preferences about sorghum characteristics. A total of 20 panicle sorting activities and 20 interviews were conducted with men and women sorghum producers. Based on their roles and responsibilities in sorghum production and processing, farmers associated specific panicle types, plant types, and grain traits with aspects of pest control, threshability, storage duration, and yield. Farmers preferred open panicles and droopy architecture for disease and pest control; hard grains for storage and appropriate ratios of flour and grits; high density of grain on the panicle for yield; and specific glume qualities for threshability. Breeding programs need to consider these regional preferences and gender roles to develop appropriate material and increase adoption of productive varieties
Two in one sweep: aluminum tolerance and grain yield in P-limited soils are associated to the same genomic region in West African Sorghum
Background
Sorghum (Sorghum bicolor L. Moench) productivity is severely impeded by low phosphorus (P) and aluminum (Al) toxic soils in sub-Saharan Africa and especially West Africa (WA). Improving productivity of this staple crop under these harsh conditions is crucial to improve food security and farmerâs incomes in WA.
Results
This is the first study to examine the genetics underlying sorghum adaptation to phosphorus limitation in a wide range of WA growing conditions. A set of 187 diverse sorghum genotypes were grown in 29 âP andâ+âP field experiments from 2006-2012 in three WA countries. Sorghum grain yield performance under âP andâ+âP conditions was highly correlated (râ=â0.85***). Significant genotype-by-phosphorus interaction was detected but with small magnitude compared to the genotype variance component. We observed high genetic diversity within our panel, with rapid linkage disequilibrium decay, confirming recent sequence based studies in sorghum. Using genome wide association mapping based on 220 934 SNPs we identified one genomic region on chromosome 3 that was highly associated to grain yield production. A major Al-tolerance gene in sorghum, SbMATE, was collocated in this region and SbMATE specific SNPs showed very high associations to grain yield production, especially under âP conditions, explaining up to 16% of the genotypic variance.
Conclusion
The results suggest that SbMATE has a possible pleiotropic role in providing tolerance to two of the most serious abiotic stresses for sorghum in WA, Al toxicity and P deficiency. The identified SNPs can help accelerate breeding for increased sorghum productivity under unfavorable soil conditions and contribute to assuring food security in WA
Increase in EPI vaccines coverage after implementation of intermittent preventive treatment of malaria in infant with Sulfadoxine -pyrimethamine in the district of Kolokani, Mali: Results from a cluster randomized control trial
<p>Abstract</p> <p>Background</p> <p>Even though the efficacy of Intermittent Preventive Treatment in infants (IPTi) with Sulfadoxine-Pyrimethamine (SP) against clinical disease and the absence of its interaction with routine vaccines of the Expanded Immunization Programme (EPI) have been established, there are still some concerns regarding the addition of IPTi, which may increase the work burden and disrupt the routine EPI services especially in Africa where the target immunization coverage remains to be met. However IPTi may also increase the adherence of the community to EPI services and improve EPI coverage, once the benefice of strategy is perceived.</p> <p>Methods</p> <p>To assess the impact of IPTi implementation on the coverage of EPI vaccines, 22 health areas of the district of Kolokani were randomized at a 1:1 ratio to either receive IPTi-SP or to serve as a control. The EPI vaccines coverage was assessed using cross-sectional surveys at baseline in November 2006 and after one year of IPTi pilot-implementation in December 2007.</p> <p>Results</p> <p>At baseline, the proportion of children of 9-23 months who were completely vaccinated (defined as children who received BGG, 3 doses of DTP/Polio, measles and yellow fever vaccines) was 36.7% (95% CI 25.3% -48.0%). After one year of implementation of IPTi-SP using routine health services, the proportion of children completely vaccinated rose to 53.8% in the non intervention zone and 69.5% in the IPTi intervention zone (P <0.001).</p> <p>The proportion of children in the target age groups who received IPTi with each of the 3 vaccinations DTP2, DTP3 and Measles, were 89.2% (95% CI 85.9%-92.0%), 91.0% (95% CI 87.6% -93.7%) and 77.4% (95% CI 70.7%-83.2%) respectively. The corresponding figures in non intervention zone were 2.3% (95% CI 0.9% -4.7%), 2.6% (95% CI 1.0% -5.6%) and 1.7% (95% CI 0.4% - 4.9%).</p> <p>Conclusion</p> <p>This study shows that high coverage of the IPTi can be obtained when the strategy is implemented using routine health services and implementation results in a significant increase in coverage of EPI vaccines in the district of Kolokani, Mali.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov <a href="http://www.clinicaltrials.gov/ct2/show/NCT00766662">NCT00766662</a></p
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