Larvicidal activity of some selected medicinal plant extracts against the vector of filariasis

The present study assessed the role of larvicidal activities of hexane, ethyl acetate and methanol dried leaf and bark extracts of Ocimum gratissimum, Gleditsia triacanthos, Eucalyptus sglobulus and Azadirachta aindica against the fourth instar larvae of filariasis vector, Culex quinquefasciatus mosquito (Diptera: Culicidae). Larvicidal activities of four medicinal plant extracts were studied in the range of 4.69 to 1000 mg/l in the laboratory bioassays against early 4th instar larvae of Culex quinquefasciatus. The mortality data were subjected to probit analysis to determine the lethal concentrations (LC50 and LC90) to kill 50 and 90 per cent of the treated larvae of the respective species. All plant extracts showed moderate effects after 24 h of exposure; however, the highest toxic effect of leaf methanol extract of Ocimum gratissimum, bark ethyl acetate extract of Eucalyptus globulus, methanol extract of Azadirachta indicia and methanol bark extract of Gleditsia triacanthos against the larvae of Culex quinquefasciatus with LC50=43.00, 41.02, 40.12 and 20.36 mg/l; LC90=278.32, 218.72, 215.01 and 86.29 mg/l respectively. The result of findings shows that leaf and bark extract of G. tricantha, A .indica, O. gratissimum and E .globulus can be developed as ecofriendly larvicides

Study of Cypermethrin Cytogenesis effects on Human Lymphocytes Using In-Vitro Techniques

The Cytogenetic effects of Cypermethrin a synthetic pyrithroid insecticide was investigated on human lymphocytes cultured in-vitro. Utilizing the trypan blue dye exclusion technique assay the LC50 of cypermethrin was found to be 36 uM. Based on LC50 value,  hypermethrin was found to be low toxic to lymphocyte culture. Cypermethrin showed an increase in the frequency of chromosomal aberrations and found to be significant. Karyotype analysis revealed more satellite associations and chromosomal breaks in cypermethrin treated samples. Low-doses of the pesticide also induced singlestrand breaks in the DNA as assessed by comet assay. The pesticide caused increase in the comet tail length with increase in pesticide concentration, implicating genotoxicity in somatic cells. It is concluded that In vitro assays could give important information of the mechanism of toxicity at low dosages and impact on genetic material of human origi

Study of Cypermethrin Cytogenesis effects on Human Lymphocytes Using In-Vitro Techniques

The Cytogenetic effects of Cypermethrin a synthetic pyrithroid insecticide was investigated on human lymphocytes cultured in-vitro. Utilizing the trypan blue dye exclusion technique assay the LC50 of cypermethrin was found to be 36 uM. Based on LC50 value, cypermethrin was found to be low toxic to lymphocyte culture. Cypermethrin showed an increase in the frequency of chromosomal aberrations and found to be significant. Karyotype analysis revealed more satellite associations and chromosomal breaks in cypermethrin treated samples. Low-doses of the pesticide also induced singlestrand breaks in the DNA as assessed by comet assay. The pesticide caused increase in the comet tail length with increase in pesticide concentration, implicating genotoxicity in somatic cells. It is concluded that In vitro assays could give important information of the mechanism of toxicity at low dosages and impact on genetic material of human origin

Larvicidal and ovicidal activity of seven essential oil against lepidopteran pest S.litura (lepidoptera: noctuidae)

Abstract The larvicidal and ovicidal effects of seven medicinal plant oil were investigated against the fourth-instar larvae of S.litura, (Lepidoptera: Noctuidae). The aim of this study was to evaluate the toxic effects of Zingiber officinale, Ocimum basilicum, cyperus scariosus, Pimpinella anism, Nigella sativa, Rosmarinus officinais, and Cercuma longa were exposed to different concentrations. All essential oils showed moderate toxic effect on lepidopteran agricultural pest of armyworm after 24hr of exposure; However, the highest larvel mortality was found i

Impact of pesticides on farmer health and the rice environment

Cet ouvrage présente les conséquences indésirables ou involontaires de l'utilisation des pesticides sur les riziculteurs et les environnements rizicoles. Ses quatorze chapitres et cinq annexes comprennent des revues bibliographiques, des résultats d'enquêtes en milieu paysan, et les résultats d'études au champ et d'études expérimentales conduites entre 1989 et 1991 aux Philippines sous la forme d'un projet multidisciplinaire rassemblant des chercheurs de l'IRRI, du NRI (Angleterre), de l'ORSTOM (France) et de l'UPLB (Philippines). Les études bibliographiques portent sur les méthodes d'analyse des effets de l'utilisation des agrochimiques, le comportement des pesticides appliqués dans les environnements rizicoles, les effets indésirables ou involontaires sur la qualité des eaux, les poissons et les autres vertébrés, les invertébrés aquatiques et telluriques, et la microflore des rizières et le rôle des législations internationales et nationales dans le marché et l'utilisation des pesticides. Les études expérimentales et les enquêtes concernent les effets environnementaux des pesticides sur les environnements rizicoles des Philippines, les perceptions et les connaissances qui gouvernent l'utilisation et les erreurs d'utilisation des pesticides par les riziculteurs et les effets à long terme, médicaux et économiques, de l'exposition des riziculteurs philippins aux pesticides. L'ouvrage comporte également 250 pages de bibliographie annotées sur ces mêmes sujets. (Résumé d'auteur

Modelling vector-borne and other parasitic diseases. Proceedings of a workshop

Session one of this report highlights ILRAD's research programs and the modelling needs of ILRAD and FAO. Session two deals with vector and helminth population dynamics with particular reference to ticks, tsetse and helminth. Parasite transmission and host parasite interaction are discussed in sessions three and four respectively. These two sessions deal with theileria, trypanosomes and leishmania. Parasite variations and polymorphism is the topic of session five. Session six discusses the effect of disease control programs and session seven reviews modelling systems. The last two sessions deal with the application of modelling, and collection, collation, analysis and dissemination of data on vector-borne and other parasitic diseases

African Handbook of Climate Change Adaptation

This open access book discusses current thinking and presents the main issues and challenges associated with climate change in Africa. It introduces evidences from studies and projects which show how climate change adaptation is being - and may continue to be successfully implemented in African countries. Thanks to its scope and wide range of themes surrounding climate change, the ambition is that this book will be a lead publication on the topic, which may be regularly updated and hence capture further works. Climate change is a major global challenge. However, some geographical regions are more severly affected than others. One of these regions is the African continent. Due to a combination of unfavourable socio-economic and meteorological conditions, African countries are particularly vulnerable to climate change and its impacts. The recently released IPCC special report "Global Warming of 1.5º C" outlines the fact that keeping global warming by the level of 1.5º C is possible, but also suggested that an increase by 2º C could lead to crises with crops (agriculture fed by rain could drop by 50% in some African countries by 2020) and livestock production, could damage water supplies and pose an additonal threat to coastal areas. The 5th Assessment Report produced by IPCC predicts that wheat may disappear from Africa by 2080, and that maize— a staple—will fall significantly in southern Africa. Also, arid and semi-arid lands are likely to increase by up to 8%, with severe ramifications for livelihoods, poverty eradication and meeting the SDGs. Pursuing appropriate adaptation strategies is thus vital, in order to address the current and future challenges posed by a changing climate. It is against this background that the "African Handbook of Climate Change Adaptation" is being published. It contains papers prepared by scholars, representatives from social movements, practitioners and members of governmental agencies, undertaking research and/or executing climate change projects in Africa, and working with communities across the African continent. Encompassing over 100 contribtions from across Africa, it is the most comprehensive publication on climate change adaptation in Africa ever produced