529 research outputs found
Biological effects of Physalis peruviana L. (Solanaceae) crude extracts and its major withanolides on Ceratitis capitata Wiedemann (Diptera: Tephritidae)
Biological effects of Physalis peruviana crude extracts and its major withanolides (withanolide E and 4-Ăź-hydroxywithanolide E) were investigated on larvae and adults of the fruit fly Ceratitis capitata. High concentrations of crude extracts (10000 and 35000 ppm) in larval diet caused 100% mortality while low concentration (1000 ppm) caused significative differences in larval mortality, development delay and puparia length. Withanolide E and 4-Ăź-hydroxywithanolide E (500 ppm) also produced significative mortality on larvae. The application of crude extracts to adults drinking vessels caused significative lethal effects at 10000 and 35000 ppm. These data indicate that P. peruviana crude extracts and its two major withanolides could be used to develop baits to control C.capitata.EEA ChubutFil: Cirigliano, A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de QuĂmica Orgánica; ArgentinaFil: Colamarino, I. Universidad de Buenos Aires. Facultad de AgronomĂa. Cátedra de ZoologĂa AgrĂcola; ArgentinaFil: Mareggiani, G. Universidad de Buenos Aires. Facultad de AgronomĂa. Cátedra de ZoologĂa AgrĂcola; ArgentinaFil: Bado, Silvina Graciela. Instituto Nacional de TecnologĂa Agropecuaria (INTA). EstaciĂłn Experimental Agropecuaria Chubut; Argentin
Involving Stakeholders in Crop-Livestock Systems Analysis: Innovation Platforms in Burkina Faso and Niger, West Africa
The development of markets and agricultural productivity need participative research approaches that involve farmers, stakeholders and actors in the value chains of agricultural products and inputs. This study illustrates the use of multi-stakeholder platforms to address critical issues that often curtail effective implementation of development strategies and achievement of objectives. The process used to facilitate stakeholder participation and achieve enhanced understanding of collective actions to achieve objectives is illustrated by case studies in Niger and Burkina Faso. The process that determines the causal relationships among the various problems is also presented; results from the process can be used to determine entry points for addressing system challenges. Finally, the study offers specific insights and analysis related to small-ruminant and feed value chains within Niger and Burkina Faso. The strengths and weaknesses of each node of the value chain are assessed and appropriate upgrading, management, and development strategies suggested. Entry points for action and strategies for intervention are identified to improve functioning of the crop-livestock value chain and the productivity of agro-pastoral farming systems. Participative analysis and understanding of the functioning of agricultural value chains enable farmers and actors to improve agricultural productivity and marketing. The multi-stakeholder platform approach is a more suitable tool for socio-economic analysis of integrated systems, and identification and implementation of development strategies, than traditional disciplinary research approaches
Effet de la combinaison des fumures organo-minérales et de la rotation niébé-mil sur la nutrition azotée et les rendements du mil au sahel
Peu de données existent sur la contribution en azote des légumineuses, et leurs impacts en présence des fumures sur la nutrition azotée des céréales. Ainsi, pour évaluer les effets du niébé et des fumures organo-minérales sur la nutrition azotée et les rendements du mil subséquent, une expérimentation a été conduite de 2008 à 2009 à Sadoré au Niger. Dans un dispositif en split-plot, trois doses de résidus, de fumier et d’engrais minéraux ont été appliquées dans une rotation niébé-mil. La méthode isotopique de 15N a été utilisée pour déterminer le coefficient réel d’utilisation d’engrais azoté (CRU). En présence de résidus, le CRU a varié de 16 à 23%. Les doses du fumier ont entraîné sa variation de 16 à 22%. Le CRU du mil subséquent était de 30% contre 22% pour le mil en monoculture. Le mil subséquent a prélevé du sol 54 kg N ha-1 contre 38 kg N ha-1 pour le mil en continu. Les doses des fumures et leur combinaison dans les systèmes de culture, ont augmenté les rendements du mil de 17 à 272%. La nutrition azotée et la productivité des systèmes peuvent donc être améliorées en combinant les fumures organo-minérales et les rotations avec légumineuses.Mots clés : Céréale, légumineuse, rotation, azote, dilution isotopique, Niger
Integrated Management of Soil Fertility and Land Resources in Sub-Saharan Africa: Involving Local Communities
The soils of sub-Saharan Africa are characterized by their poverty in nutrients along with low clay and organic carbon content and low exchange capacity. There is high pressure on land resources with the quick growth of population and demand for food. Maintaining the fertility of cultivated soils and land resources is a challenge. Since the paradigm of “external input” in the 1960s and 1970s, to the latest concept of integrated soil fertility management, most of the approaches remain crop oriented or livestock oriented with less attention to local communities (LC), which are at the heart of land resource management. This chapter suggests a new integrated and holistic approach involving LC for land resources management, including cultivated soils and rangelands. A global framework is proposed for development of management options of land resources with LC. It is a dynamic process of participative management of lands as providers of services for the entire community
H3-receptor regulation of vascular gastrin and somatostatin releases by the isolated rat stomach.
We have studied the effects of the H3-receptor agonist (R) alpha-methylhistamine [(R) alpha-MeHA] and the H3-receptor antagonist thioperamide (Thiop) on basal- and carbachol-stimulated vascular gastrin release (GR) and somatostatin release (SR) by the isolated rat stomach. Carbachol dose-dependently stimulated and inhibited GR and SR, respectively. Maximal stimulation of GR (500 +/- 112 percent of basal; p < .01), and maximal inhibition of SR (-62 +/- 9 percent under basal; p < .01) were obtained with 1 micron carbachol. Neither (R)alpha-MeHA nor Thiop, up to 10 microns, affected GR. However, SR was dose-dependently enhanced by Thiop (25 +/- 8 percent for 10 microns). Carbachol stimulation of GR was strongly inhibited by Thiop (30 +/- 7 percent for 100 nM and 73 +/- 14 percent for 1 microgram), whereas it was potentiated by (R)alpha-MeHA. Carbachol inhibition of SR was reversed by Thiop and (R)alpha-MeHA. However, the reversal effect of (R)alpha-MeHA was prevented by the CCKB/gastrin receptor antagonist PD134308. These results support H3-receptor regulation of basal and cholinergically-stimulated GR and SR
Evaluation of the feed quality of six dual purpose pearl millet varieties and growth performance of sheep fed their residues in Niger
Pearl millet (Pennisetum glaucum) is a
staple food popularly cultivated by
small farmers in Niger. The stover are
also used as feeds for livestock (small
ruminant) as basal diet, especially
during the cold dry season.
ICRISAT has developed many dualpurpose
millet varieties that aim to
increase feeds for livestock while
providing grain as food to farmers. But
the nutritional quality of Stover of
these varieties for livestock are not
known.
This research aims to assess the
quality of residues of the dual-purpose
varieties and their effect on feed
intake and live weight changes of
young sheep
Women's education and health inequalities in under-five mortality in selected sub-Saharan African countries, 1990–2015
The aim of the study was to analyse trends in the relationship between mother’s educational
level and mortality of children under the year of five in Sub-Saharan Africa, from 1990 to
2015.Data used in this study came from different waves of Demographic and Health Surveys
(DHS) of Sub-Saharan countries. Logistic regression and Buis’s decomposition method
were used to explore the effect of mother’s educational level on the mortality of children
under five years
Distribution and frequency of kdr mutations within Anopheles gambiae s.l. populations and first report of the ace.1 G119S mutation in Anopheles arabiensis from Burkina Faso (West Africa).
Published onlineJournal ArticleResearch Support, Non-U.S. Gov'tAn entomological survey was carried out at 15 sites dispersed throughout the three eco-climatic regions of Burkina Faso (West Africa) in order to assess the current distribution and frequency of mutations that confer resistance to insecticides in An. gambiae s.l. populations in the country. Both knockdown (kdr) resistance mutation variants (L1014F and L1014S), that confer resistance to pyrethroid insecticides, were identified concomitant with the ace-1 G119S mutation confirming the presence of multiple resistance mechanisms in the An. gambiae complex in Burkina Faso. Compared to the last survey, the frequency of the L1014F kdr mutation appears to have remained largely stable and relatively high in all species. In contrast, the distribution and frequency of the L1014S mutation has increased significantly in An. gambiae s.l. across much of the country. Furthermore we report, for the first time, the identification of the ace.1 G119S mutation in An. arabiensis populations collected at 8 sites [corrected]. This mutation, which confers resistance to organophosphate and carbamate insecticides, has been reported previously only in the An. gambiae S and M molecular forms. This finding is significant as organophosphates and carbamates are used in indoor residual sprays (IRS) to control malaria vectors as complementary strategies to the use of pyrethroid impregnated bednets. The occurrence of the three target-site resistance mutations in both An. gambiae molecular forms and now An. arabiensis has significant implications for the control of malaria vector populations in Burkina Faso and for resistance management strategies based on the rotation of insecticides with different modes of action.National Malaria Control Program (NMCP) of Burkina Fas
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