Search results for "PEST CONTROL"
showing 10 items of 221 documents
Invasive and native populations of common ragweed exhibit strong tolerance to foliar damage.
2013
8 pages; International audience; Tolerance and resistance are defence strategies evolved by plants to cope with damage due to herbivores. The introduction of exotic species to a new biogeographical range may alter the plant herbivore interactions and induce selection pressures for new plant defence strategies with a modified resource allocation. To detect evolution in tolerance to herbivory in common ragweed, we compared 3 native (North America) and 3 introduced (France) populations, grown in a common garden environment. We explored the effect of leaf herbivory on plant vegetative and reproductive traits. Plants were defoliated by hand, simulating different degrees of insect grazing by remo…
Comprehensive Analysis of Gene Expression Profiles of the Beet Armyworm Spodoptera exigua Larvae Challenged with Bacillus thuringiensis Vip3Aa Toxin
2013
Made available in DSpace on 2014-12-03T13:11:48Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-12-02Bitstream added on 2014-12-03T13:22:24Z : No. of bitstreams: 1 WOS000327944500105.pdf: 2100332 bytes, checksum: 71ea7616e9a7949eed19cff4ce56111f (MD5) Spanish Ministerio de Ciencia e Innovacion European FEDER funds Generalitat Valenciana Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Host-pathogen interactions result in complex relationship, many aspects of which are not completely understood. Vip proteins, which are Bacillus thuringensis (Bt) insecticidal toxins produced during the vegetative stage, are selectively effective against specific insect pests. This ne…
Effect of thermal treatments on vitality and physical characteristics of bean, chickpea and lentil
2012
Thermal disinfestation treatments are relatively easy to apply, leave no chemical residues and may have some fungicidal activity. However, temperature and time combinations required to kill insect pests may meet or exceed those that reduce the viability of seeds, nutrients content, shelf life or technological characteristics. The aim of this study was to investigate the effect of thermal treatments (different temperature and time combinations) on physical and biological characteristics of bean, chickpea and lentil. Seed samples of common bean, chickpea and lentil were treated at low (12, 24 or 48 h at −18 °C) or high (30, 60 or 90 min at 60 °C) temperature. Seed germination, mean germinatio…
Environmental distribution and diversity of Bacillus thuringiensis in Spain.
1998
Bacillus thuringiensis was isolated from 301 out of 1,005 samples collected in Spain from agricultural and non-cultivated soils, dust from stored products, and dead insects. Based on the production of parasporal crystals, 1,401 isolates were identified as B. thuringiensis after examining 11,982 B. thuringiensis-like colonies. We found a greater presence of B. thuringiensis in dust from grain storages than in other habitats. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the spore-crystal mixtures revealed diverse populations of B. thuringiensis which were differentiated in at least 92 distinct protein profiles. Serological identification also showed great diversity among the S…
Characterization of Bacillus thuringiensis ser. balearica (Serotype H48) and ser. navarrensis (serotype H50): two novel serovars isolated in Spain.
2000
The novel strains of Bacillus thuringiensis PM9 and NA69, isolated from soil samples in Spain, were classified and characterized in terms of their crystal proteins, plasmid profile, cry genes content, and their toxicological properties against several species of Lepidoptera, Coleoptera, and Diptera. Both strains share morphological and biochemical characteristics with previously described B. thuringiensis strains, although their unique H antigens identify them as two new serotypes. Two new serovar names, B. thuringiensis serovar balearica (H serotype 48) and B. thuringiensis serovar navarrensis (H serotype 50) are proposed for the type strains PM9 and NA69, respectively.
Pythium perplexum isolated from soil in France: morphology, molecular characterisation and biological control.
2001
Pythium perplexum (F-926) was isolated from a soil sample taken in the Burgundy region in France. In 1907, it was mistakenly described by Bulter as P. vexans. Despite morphological resemblance, the comparison between the internal transcribed spacer 1 regions of the ribosomal DNA of the two fungi leaves no doubt of their different identities. P. perplexum was found to be highly pathogenic to cucumber seedlings. Damping-off disease of cucumber caused by P. perplexum can effectively be controlled by using the soil bacterium Serratia plymuthica (B-781). The details of the morphology and the molecular characterisation of P. perplexum and its biological control with S. plymuthica are described he…
Eco-physiological response of two marine bivalves to acute exposition to commercial Bt-based pesticide
2013
Microbial products based on the entomopathogenic bacterium Bacillus thuringiensis (Bt) are among the most common biopesticides used worldwide to suppress insect pests in forests, horticulture and agricultural crops. Some of the effects of commercial Bt have been recorded for terrestrial and freshwater non-target organisms but little research is available on marine fauna. Nevertheless, due to the contiguity of agro-ecosystems and coastal habitats, marine fauna may be highly influenced by this control method. We studied the effect of a commercial Bt product on the physiological and ecological responses and the energy budget of two of the most frequent marine intertidal bivalves in the Mediter…
Evaluating the quality of the Mexican fruit-fly, Anastrepha ludens, as host for the parasitoid Melittobia digitata
2013
We investigated the presence of Melittobia digitata (Hymenoptera: Eulophidae) and its associations with its natural hosts in Veracruz, Mexico. The parasitoid was confirmed to be present and found to attack prepupae of Trypoxylon and Sceliphron (Hymenoptera: Crabronidae and Sphecidae, respectively) mud daubers as well as pupae of the Mexican fruit fly Anastrepha ludens (Diptera: Tephritidae). Since A. ludens is a very important pest of citrus and mango in Mexico and Central America, we evaluated, in laboratory experiments, the quality of A. ludens as host of M. digitata comparing the development of the parasitoid in another unrelated fly species (Sarcophaga [Neobellieria] bullata) (Diptera: …
Pathogenicity of intrathoracically administrated Bacillus thuringiensis spores in Blatta orientalis.
2006
Abstract The ability of Bacillus thuringiensis to produce septicaemia in Periplaneta americana and Blatta orientalis has been investigated. Spores and crystals from several wild-type strains as well as spores of a B. thuringiensis crystal-deficient mutant, were first orally administrated at high doses, and no significant mortality was recorded. Intrathoracic injection of spore suspensions in P. americana revealed that this species is not very susceptible to B. thuringiensis spores. B. orientalis , by contrast, was found to be very susceptible to B. thuringiensis , with a LD 50 of about 35,000 spores, that is similar to that reported on Lepidoptera challenged with parenterally injected B. th…
Use of Logistic Regression for Prediction of the Fate of Staphylococcus aureus in Pasteurized Milk in the Presence of Two Lytic Phages
2010
The use of bacteriophages provides an attractive approach to the fight against food-borne pathogenic bacteria, since they can be found in different environments and are unable to infect humans, both characteristics of which support their use as biocontrol agents. Two lytic bacteriophages, vB_SauS-phiIPLA35 (phiIPLA35) and vB_SauS-phiIPLA88 (phiIPLA88), previously isolated from the dairy environment inhibited the growth of Staphylococcus aureus. To facilitate the successful application of both bacteriophages as biocontrol agents, probabilistic models for predicting S. aureus inactivation by the phages in pasteurized milk were developed. A linear logistic regression procedure was used to desc…