Variation in the susceptibility of Anopheles gambiae to botanicals across a metropolitan region of Nigeria

Pesticide resistance is normally associated with genetic changes, resulting in varied responses to insecticides between different populations. There is little evidence of resistance to plant allelochemicals; it is likely that their efficacy varies between genetically diverse populations, which may lead to the development of resistance in the future. This study evaluated the response of Anopheles gambiae (larvae and adults) from spatially different populations to acetone extracts of two botanicals, Piper guineense and Eugenia aromatica. Mosquito samples from 10 locations within Akure metropolis in Southwest Nigeria were tested for variation in susceptibility to the toxic effect of botanical extracts. The spatial distribution of the tolerance magnitude (T.M.) of the mosquito populations to the botanicals was also mapped. The populations of An. gambiae manifested significant differences in their level of tolerance to the botanicals. The centre of the metropolis was the hot spot of tolerance to the botanicals. There was a significant positive correlation between the adulticidal activities of both botanicals and initial knockdown. Hence, knockdown by these botanicals could be a predictor of their subsequent mortality. In revealing variation in response to botanical pesticides, our work has demonstrated that any future use of botanicals as alternative environmentally friendly vector control chemicals needs to be closely monitored to ensure that resistance does not develop

Pengaruh Insektisida Nabati Ekstrak Tanaman Kemangi (Ocimum basilicum) dan Daun Sirih Terhadap Mortalitas Lalat Buah (Bactrocera sp.)

Bactrocera sp. is one type of insect pests that can cause damage to some types of fruit. Insect pest control using chemical insecticides can cause various disadvantages such as environmental pollution. The use of natural ingredients such as basil plants containing a secondary compound of methyl eugenol which is an attractant for fruit fly pests, meanwhile the contents of phenols, terpenoids, eugenol, and kavichol on betel leaves are toxic to insects, it can be an alternative to make a botanical insecticide. The purpose of this research is to know the effect of botanical insecticide extracts of basil plant (Ocimum basilicum) and betel leaf on mortality of fruit fly (Bactrocera sp.). This research is an experimental research with quantitative descriptive, data analysis using analysis of variance of two lanes (Twoway Anova).The study consisted of 6 treatments with two factors, the first factor is an insecticides with different solvents (A), A1= botanical Insecticide extracts of betel leaf + basil plants with ethanol solvent 70%; and A2= Botanical insecticide extracts of betel leaf+basil plants with methanol solvent 70% and the second factor, the concentration of botanical insecticide (K), K1= Concentration 30%; K2= Concentration 40%; and K3= Concentration 50%. The result can be conclude that botanical insecticide extracts of basil plant and betel leaf effected to kill fruit fly pests

New adhesive traps to monitor urban mosquitoes with a case study to assess the efficacy of insecticide control strategies in temperate areas

Background: Urban mosquitoes in temperate regions may represent a high nuisance and are associated with the risk of arbovirus transmission. Common practices to reduce this burden, at least in Italian highly infested urban areas, imply calendar-based larvicide treatments of street catch basins – which represent the main non-removable urban breeding site and/or insecticide ground spraying. The planning of these interventions, as well as the evaluation of their effectiveness, rarely benefit of adequate monitoring of the mosquito abundance and dynamics. We propose the use of adhesive traps to monitor Aedes albopictus and Culex pipiens adults and to evaluate the efficacy of insecticide-based control strategies. Methods: We designed two novel types of adhesive traps to collect adult mosquitoes visiting and/or emerging from catch basins. The Mosquito Emerging Trap (MET) was exploited to assess the efficacy of larvicide treatments. The Catch Basin Trap (CBT) was exploited together with the Sticky Trap (ST, commonly used to collect ovipositing/resting females) to monitor adults abundance in the campus of the University of Rome “Sapienza” - where catch basins were treated with Insect Growth Regulators (IGR) bi-monthly and Low-Volume insecticide spraying were carried out before sunset - and in a nearby control area. Results: Results obtained by MET showed that, although all monitored diflubenzuron-treated catch basins were repeatedly visited by Ae. albopictus and Cx. pipiens, adult emergence was inhibited in most basins. Results obtained by ST and CBT showed a significant lower adult abundance in the treated area than in the untreated one after the second adulticide spraying, which was carried out during the major phase of Ae. albopictus population expansion in Rome. Spatial heterogeneities in the effect of the treatments were also revealed. Conclusions: The results support the potential of the three adhesive traps tested in passively monitoring urban mosquito adult abundance and seasonal dynamics and in assessing the efficacy of control measures. ST showed higher specificity for Ae. albopictus and CBT for Cx. pipiens. The results also provide a preliminary indication on the effectiveness of common mosquito control strategies carried out against urban mosquito in European urban areas

Nematicidal activity of plant extracts against the root-knot nematode, Meloidogyne incognita

Nematicidal activity of extracts from plants was assayed against Meloidogyne incognita. In laboratory assays extracts from tobacco (Nicotiana tabacum L), clove (Syzygium aromaticum L), betelvine (Piper betle L), and sweet flag (Acorus calamus L) were most effective in killing the nematode, with an EC50 that was 5-10 times lower than the EC50 of the synthetic pesticides chlorpyrifos, carbosulfan and deltamethrin. The shapes of the dead nematodes differed in a characteristic way, and groups of pesticides and plant extracts could clearly be distinguished based on this phenomenon, which may be an indicator for the modes of action of the tested pesticides. In a greenhouse bioassay clove bud and betelvine were tested as mulch. Experiments revealed that the total number of live nematodes on roots of pepper plants treated with mulch of the clove bud was 7% of that of the controls and did not differ significantly from that of plants treated with the recommended synthetic pesticide carbofuran. The application of clove buds as a botanical pesticide for future use against nematodes is highly promising since clove is the 6th major plant grown on Bangka Island, and the market value of clove has decreased sharply over the last year

Investigations on Tuta absoluta (Lepidoptera: Gelechiidae): larval infestation on the tomato cultivated in open field and evaluation of five essential oils against larvae in laboratory

Abstract The tomato miner Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) is a Neotropical species, which cause serious damages to tomato in spread areas. It appeared in 2008 in Italy, where it seriously threatened tomato production both in greenhouse and open field cultivations. In this work a study on infestation by this leafminer on leaves was conducted in an organic cultivation of tomato (Lycopersicon esculentum Mill.) "Pizzutello" variety in Sicily (Italy), and the insecticidal activity of 5 essential oils (EOs) on T. absoluta was evaluated in laboratory. EOs of basil, cypress, laurel, peppermint and Spanish oregano were used against 3rd- and 4th-instar larvae to assess contact effects and, only for oregano and laurel, inhalation effects. Results showed that the infestation in field had a variable trend showing peaks in two periods, in the months of July and October. Larvae of T. absoluta developed on leaves for most of the growing season of tomato showing a peak of 1.5 larva per leaf in the first part of July decreasing in the subsequent months. Results on the use of essential oils against the leafminer showed a good larvicidal effects confirming their use as potential alternative for pest control. Basil, cypress and laurel oils showed major contact efficacy. Inhalation effects of the oils of oregano and laurel increased with increasing their doses with a positive correlation. Oregano oil was effective at lower doses than laurel

Present and future potential of plant-derived products to control arthropods of veterinary and medical significance

The use of synthetic pesticides and repellents to target pests of veterinary and medical significance is becoming increasingly problematic. One alternative approach employs the bioactive attributes of plant-derived products (PDPs). These are particularly attractive on the grounds of low mammalian toxicity, short environmental persistence and complex chemistries that should limit development of pest resistance against them. Several pesticides and repellents based on PDPs are already available, and in some cases widely utilised, in modern pest management. Many more have a long history of traditional use in poorer areas of the globe where access to synthetic pesticides is often limited. Preliminary studies support that PDPs could be more widely used to target numerous medical and veterinary pests, with modes of action often specific to invertebrates. Though their current and future potential appears significant, development and deployment of PDPs to target veterinary and medical pests is not without issue. Variable efficacy is widely recognised as a restraint to PDPs for pest control. Identifying and developing natural bioactive PDP components in place of chemically less-stable raw or 'whole’ products seems to be the most popular solution to this problem. A limited residual activity, often due to photosensitivity or high volatility, is a further drawback in some cases (though potentially advantageous in others). Nevertheless, encapsulation technologies and other slow-release mechanisms offer strong potential to improve residual activity where needed. The current review provides a summary of existing use and future potential of PDPs against ectoparasites of veterinary and medical significance. Four main types of PDP are considered (pyrethrum, neem, essential oils and plant extracts) for their pesticidal, growth regulating and repellent or deterrent properties. An overview of existing use and research for each is provided, with direction to more extensive reviews given in many sections. Sections to highlight potential issues, modes of action and emerging and future potential are also included

Do Pesticide Hazards to Human Health and Beneficial Insects Cause or Result from IPM Adoption? Mixed Messages from Farmer Field Schools in Nicaragua

This paper analyzes the interaction between farmer training in pest management and effects on acute pesticide poisoning and populations of beneficial insects in Nicaragua. Using farm level data from Nicaraguan bean growers, including graduates of Farmer Field Schools (FFS), other integrated pest management (IPM) outreach methods, and farmers without exposure to IPM, we found that small farmers are influenced by pesticide-related acute illness experiences when adopting IPM practices and making decisions about pesticide use. However, exposure to IPM extension programs failed to reduce the use of highly toxic pesticides and increased the number of self-reported acute illness symptoms during the most recent bean crop season. IPM training did result in growth of beneficial insect populations.ecosystem service, integrated pest management, agricultural extension, Nicaragua, Farm Management, Q16,

Galleria mellonella (L.) (Pyralidae) und Spodoptera exigua (Hübner) (Noctuidae): Wirkungsunterschiede zwischen XenTari® (Bacillus thuringiensis aizawai), NeemAzal T/S® und ihren Kombinationen

Both, G. mellonella and S. exigua, are most important pests in tropical countries. G. mellonella has five to six generations per year (Abid et al. 1997; Ali 1996), there, and feeding in bee combs they find, besides wax, residues of honey, insect skin and pollen (Hachiro & Knox 2000). Li et al. (1987) have shown the efficacy of Bacillus thuringiensis aizawai against G. mellonella. It is registered in the EU as Mellonex for its control, but NeemAzal T/S may also be active, and will have some advantages (Leymann et al. 2000, Melathopoulos et al. 2000). Therefore we conducted new studies here, on the results we shall report. S. exigua is an important polyphagous pest of crops in tropical areas (Brown & Dewhurst 1975). By repeated control with synthetic insecticides, especially by illiterate farmers (Armes et al. 1992; Aggarwal et al. 2006a) resistance to a lot of those insecticides has been built up, making plant protection very difficult. Therefore the need is pronounced for microbial and botanical pesticides (Nagarkatti 1982; Rao et al. 1990), which have different modes of action than synthetic insecticides. Aggarwal et al. (2006b) have started to test such ingredients, but the time of observation was too short (3 days), since the effects of Neem products occur later than those of synthetic insecticides (Basedow et al. 2002). So we conducted new, longer lasting experiments (with 5 to 30 days), on which we give a report here. The experiments were conducted during guest stays of the three co-authors (from Mymensingh, Bangladesh, from Nazreth, Ethiopia, and from Khartoum, Sudan) at the Experimental Station of the Institute of Phytopathology and Applied Zoology at Giessen Univerity.Im Labor wurden die Larven mit trockenem Futter versorgt, das vorher für 20 Sek. in die Testlösung getaucht war. Die Testlösungen, auch in der Kontrolle, wurden mit dem anionischen Detergens Triton X 100 versetzt (10%, davon 0.1 ml). XenTari wurde mit 0.5, 1 und 2 mg/l getestet, NeemAzal mit 2, 4 und 8 mg/l. Bei G. mellonella war die höchste korrigierte Mortalität bei XenTari nach 4 Wochen 77%, bei NeemAzal T/S 100%. So wird letzteres empfohlen. Bei Spodoptera exigua im zweiten Larvenstadium bewirkte XenTari nach 3 Wochen eine maximale Wirkung von 95.6%, während NeemAzal T/S bereits nach 7 Tagen 100% erreichte. Im vierten Larvenstadium erreichte NeemAzal TS eine Mortalität von 46%. Wurden aber beide Präparate bei halber Dosis nacheinander appliziert, war die Wirkung nach 5 Tagen 73% (XenTari zuerst) bzw. 98.8% (NeemAzal T/S zuerst). Letztere Kombination wird für den Bauwollanbau in den Tropen empfohlen, um durch deren Zwischenschaltung die Resistenzbildung gegenüber synthetischen Insektiziden zu vermindern

Agro-pastoral and agro-ecological baseline survey. Methodology : short term consultancy 10-30 March 2002

Mission pour la définition d'une méthode de prise d'information et de suivi concernant l'environnement dans les régions où est appliquée la lutte contre les tsé-tsé et les trypanosomoses animales et humaines. Le rapport précise les problèmes environnementaux dominants spécifiques à chaque pays, il précise un certain nombre d'indicateurs de suivi, esquisse les méthodes de collecte des données et les conditions de réalisation à respecter pour leur mise en oeuvre. (Résumé d'auteur