Changes in Parasitoid Communities Over Time and Space: A Historical Case Study of the Maize Pest Ostrinia nubilalis

Understanding the ways in which human environmental modifications affect biodiversity is a key challenge in conservation planning, pest control and evolutionary ecology. Parasitoid communities, particularly those associated with agricultural pests, may be susceptible to such modifications. We document here changes in the larval parasitoid communities of Ostrinia nubilalis — the main pest of maize — and its sibling species O. scapulalis, based on two historical datasets, one collected from 1921–1928 and the other from 2001–2005. Each of these datasets encompasses several years and large geographical areas and was based on several thousands/millions of host larvae. The 80-year interval between the two datasets was marked by a decrease in O. nubilalis parasitism to about two thirds its initial level, mostly due to a decrease in the rate of parasitism by hymenopterans. However, a well balanced loss and gain of species ensured that species richness remained stable. Conversely, O. scapulalis displayed stable rates of parasitism over this period, with a decline in the species richness of its parasitoid community. Rates of parasitism and species richness in regions colonized by O. nubilalis during the 1950s were one half to one third those in regions displaying long-term colonisation by this pest. During the recent human activity-driven expansion of its range, O. nubilalis has neither captured native parasitoids nor triggered parasite spill back or spill over

La culture du Lathyrus en Aquitaine : passé, présent et perspectives

Lots of traditional cultivations have been neglected with the evolution of agricultural methods, but some of them would find again some interest. We examine here the genus Lathyrus, a member of Leguminosae family, still cultivated in South-West of France (Aquitaine).L'évolution des pratiques agricoles a conduit à l'abandon d'un certain nombre de cultures traditionnelles dont quelques unes, cependant, pourraient retrouver une certaine actualité. Le cas du genre Lathyrus, une légumineuse encore cultivée en Aquitaine, est examinée.Regnault-Roger Catherine. La culture du Lathyrus en Aquitaine : passé, présent et perspectives. In: Journal d'agriculture traditionnelle et de botanique appliquée, 34ᵉ année,1987. pp. 89-94

The nutritional incidence of flavonoids: some physiological and metabolic considerations

cited By 40International audienceExamination of the physiological activity of flavonoids in relation to their antiscorbutic properties shows that some of these compounds, the flavan-3=ols, have a particular nutritional impact and consequently should be distinguished from the rest of the flavonoids and polyphenolds. Therefore, the use of the term 'Vitamin P' and 'Bioflavonoids' is also discussed

Diversification des stratégies de protection des plantes : Intérêt des monoterpènes

cited By 1International audiencePlant protection requires alternative strategies to control pest insects. Among these strategies, the use of allelochemicals could be focused on two ways involving: - the internal defences of plants by the modification and the orientation of their metabolisms to enhance the production of self-defence components, - the external defences of plants by utilisation of insecticidal soaps containing plant or natural biodegradable products. The ample distribution of terpenoids and their widespread range of activities point them to be examined as new ecological agents for plant protection and insect control. In order to classify their efficiency, the insecticidal activity of monoterpenes, identified as main components of essential oils, was evaluated on insects belonging to Coleoptera, Diptera and Homoptera orders. The structure-activity relationships are discussed

Risks of biocontrol agents containing compounds of botanical origin or semiochemicals

cited By 2International audienceSemiochemicals and botanicals have the potential to control plant pests or diseases but before they can be used as plant protection products they have to be registered. In the registration process, the risk assessments associated with their properties and their uses have to be evaluated. These risks are linked to the toxicity on the organisms and populations, as well as the exposure. Potential hazards for humans (operators, bystanders, consumers), wildlife and the environment (fate in air, soil and water, non target organisms including the routes to which they are exposed) must be identified and evaluated depending on the uses of the end-products. Semiochemicals and botanicals are currently involved in several approaches for pest biocontrol: insect detection and monitoring, mating disruption and mass trapping for pheromones, insecticide formulations and enhancement of plant resistance for plant allelochemicals and botanicals. These approaches are discussed according to the risk assessment. © 2011 Springer Science+Business Media B.V

Albanie : succès d'une politique alimentaire

Regnault Roger Catherine. Albanie : succès d'une politique alimentaire. In: Tiers-Monde, tome 18, n°72, 1977. pp. 849-860

Botanicals in pest management

cited By 1International audienc

The potential of botanical essential oils for insect pest control

cited By 181International audienceToday, Insect Pest management (IPM) has to face up to the economic and ecological consequences of the use of pest control measures. Fifty years of sustained struggle against harmful insects using synthetic and oil-derivative molecules has produced perverse secondary effects (mammalian toxicity, insect resistance and ecological hazards). The diversification of the approaches inherent in IPM is necessary for better environmental protection. Among the alternative strategies, the use of plants, insecticidal allelochemicals appears to be promising. Aromatic plants, and their essential oils, are among the most efficient botanicals. Their activities are manifold. They induce fumigant and topical toxicity as well as antifeedant or repellent effects. They are toxic to adults but also inhibit reproduction. Although mechanisms depend on phytochemical patterns and are not yet well known, this widespread range of activities is more and more being considered for both industrial and household uses: essential oils are presently regarded as a new class of ecological products for controlling insect pests

La protection des plantes cultivées au coeur des enjeux pour l\u27agriculture durable

Lors de cette étude, sont examinée l\u27évolution des principales familles de substances phytopharmaceutiques de synthèse à usages insecticide, fongicide et herbicide, et leur incidence commerciale. Serons soulignées les mesures prises afin d\u27assurer une meilleure sécurité de leur emploi et la surveillance dont elles font l\u27objet, ainsi les démarches mises en oeuvre pour réduire l\u27utilisation des substances actives de synthèse afin diminuer leur impact environnemental. C\u27est en fait toute une profession, de l\u27agriculteur à l\u27industriel, du chercheur à l\u27administration en charge du secteur, qui s\u27est mobilisée pour créer des outils nouveaux et pour explorer des pistes pour penser autrement l\u27usage des substances phytopharmaceutiques

Comparaison des activités insecticides des monoterpènes sur deux espèces d'insectes ravageurs des cultures : Ceratitis capitata et Rhopalosiphum padi

cited By 14International audienceThe fumigant toxic effect of some monoterpenoids : α-pinene, linalol, carvacrol, eugenol, p-cymène, cinnamaldehyde, anethole, terpineol and cuminalde-hyde, was tested upon Rhopalosiphum padi and Ceratitis capitata. The sensitivity of both species to these compounds appears to be variable. The aldehyde and methoxyled monoterpenoids (cinnamaldehyde, cuminaldehyde and anethole) revealed to be more active than hydrogenated o es (α-pinene and p-cymene). The phenolic monoterpenoids present a great activity especially upon C. capitata