Search results for " pest"

Effect of Cry Toxins on Xylotrechus arvicola (Coleoptera: Cerambycidae) Larvae

2022

Simple Summary Xylotrechus arvicola is a destructive pest in vineyards (Vitis vinifera) in the main wine-producing areas of the Iberian Peninsula. X. arvicola larvae bore into the grapevine wood-making galleries, thus damaging the plant both directly and indirectly. The susceptibility of X. arvicola larvae to five coleopteran toxic Cry proteins was evaluated under laboratory conditions in order to deepen the knowledge of the effect of these proteins on this insect throughout its biological development. The Cry proteins tested could be applied to control X. arvicola larvae since they were able to kill them and cause serious alterations in the larvae during the remaining months of development…

Molecular Basis for Endocrine Disruption by Pesticides Targeting Aromatase and Estrogen Receptor

2020

The intensive use of pesticides has led to their increasing presence in water, soil, and agricultural products. Mounting evidence indicates that some pesticides may be endocrine disrupting chemicals (EDCs), being therefore harmful for the human health and the environment. In this study, three pesticides, glyphosate, thiacloprid, and imidacloprid, were tested for their ability to interfere with estrogen biosynthesis and/or signaling, to evaluate their potential action as EDCs. Among the tested compounds, only glyphosate inhibited aromatase activity (up to 30%) via a non-competitive inhibition or a mixed inhibition mechanism depending on the concentration applied. Then, the ability of the thr…

Isolation of organophosphorus-degrading bacteria from agricultural mediterranean soils

2010

Chemical Ecology of Insect Parasitoids: Essential Elements for Developing Effective Biological Control Programmes

2013

Insect parasitoids can find their hosts in complex environments and reproduce through a series of behavioural steps which are regulated mainly by chemical cues, termed semiochemicals. According to functional criteria, stimuli can be classified into four main categories: (A) cues coming from the habitat, the host microhabitat or the food plant, (B) direct host‐related cues, (C) indirect host‐related cues, and (D) cues coming from the parasitoid itself. In recent years, considerable progress has been made in elucidating the semiochemicals used by parasitoids to locate their hosts. Several studies provided interesting prospective for manipulating foraging behaviour of parasitoids in order to i…

Survey of the parasitoids of the European Sunflower MothHomoeosoma nebulella [Lep.: Pyralidae] in the palearctic region

1993

The European Sunflower MothHomoeosoma nebulella Denis & Schiffermuller is a potential pest on sunflower in France. The parasitoids of this moth are little known. We present here original data obtained in the south of France together with previous survey. Some parasitoids we found were new records onH. nebulella. The relative weakness of the parasite complex ofH. nebulella (less than 15 species) compared to that of the American Sunflower MothH. electellum (Hulst) is discussed.

Pre-release risk assessment of the egg-parasitoid Gryon pennsylvanicum for classical biological control of Leptoglossus occidentalis.

2013

Leptoglossus occidentalis Heidemann (Heteroptera: Coreidae) is a North American conifer seed pest that was accidentally introduced to Europe. In the Mediterranean area, it threatens the production of Pinus pinea Linna- eus seeds. The egg-parasitoid Gryon pennsylvanicum (Ashmead) (Hymenop- tera: Platygastridae), the main natural enemy in the native range of L. occidentalis, was imported from British Columbia to Italy. Pre-release risk assessments were made under quarantine conditions by no-choice tests conducted with na€ıve and experienced G. pennsylvanicum offering single eggs of target and non-target species for varying exposure times (1, 4, 48 h). G. pennsylvanicum successfully parasitize…

Insecticidal Activity of Strains of Bacillus thuringiensis on Larvae and Adults of Bactrocera oleae Gmelin (Dipt. Tephritidae)

1999

The olive fly, Bactrocera oleae, is the key pest on olives in the Mediterranean area. The pest can destroy, in some cases, up to 70% of the olive production. Its control relies mainly on chemical treatments, sometimes applied by aircraft over vast areas, with their subsequent ecological and toxicological side effects. Bacillus thuringiensis is a spore-forming soil bacterium which produces a protein crystal toxic to some insects, including the orders of Lepidoptera, Diptera, and Coleoptera and other invertebrates. The aim of this study was to search for isolates toxic to B. oleae. Several hundred B. thuringiensis isolates were obtained from olive groves and olive presses in different areas o…

Interspecific extrinsic and intrinsic competitive interactions in egg parasitoids

2012

Interspecific competitive interactions can occur either between adult parasitoids searching/exploiting hosts (extrinsic competition) or between parasitoid larvae developing within the same host (intrinsic competition). Understanding how interspecific competition between parasitoids can affect pest suppression is important for improving biological pest control. The purpose of this work was to review both extrinsic and intrinsic competition between egg parasitoid species. These are organisms that are often candidates for biological control programs due to their ability to kill the pest before the crop feeding stage. We first reviewed the literature about interspecific competitive abilities of…

Metarhizium anisopliae, a potential agent for the control of grape phylloxera

2004

This investigation deals with the control effects of the insect pathogenic fungus Metarhizium anisopliae var. anisopliae on Daktulosphaira vitifoliae. In pot experiments, the soil surrounding phylloxera-infected grapes was inoculated with barley colonised with M. anisopliae. After thirty-two days, ineight of ten Metarhizium-applied pots nofresh phylloxera infections could be observed.In two of ten plants, a few fresh nodositiessingly occupied with phylloxera or phylloxeraeggs could be found. In all untreated plants,fresh nodosities with either single (two of sixplants) or multiple (four of six plants)occupation with phylloxera could be observed.M. anisopliae could be re-isolated in aconcent…

Detection and discrimination of organophosphorus pesticides in water by using a colorimetric probe array

2014

[EN] Detection and discrimination of several organophosphorus pesticides in water using a colorimetric probe array containing twelve dyes has been achieved. A clear discrimination for malathion, leptophos, dichlorvos, dibrom and diazinon was observed. The array was used to determine the concentration of diazinon in orange leaves