Search results for "Acte"
showing 10 items of 9295 documents
Symbiont Genomic Features and Localization in the Bean Beetle Callosobruchus maculatus
2021
A pervasive pest of stored leguminous products, the bean beetle Callosobruchus maculatus (Coleoptera: Chrysomelidae) associates with a simple bacterial community during adulthood. Despite its economic importance, little is known about the compositional stability, heritability, localization, and metabolic potential of the bacterial symbionts of C. maculatus. In this study, we applied community profiling using 16S rRNA gene sequencing to reveal a highly conserved bacterial assembly shared between larvae and adults. Dominated by Firmicutes and Proteobacteria, this community is localized extracellularly along the epithelial lining of the bean beetle's digestive tract. Our analysis revealed that…
Thermal Tolerance is linked with Virulence in a Fish Pathogen
2017
ABSTRACTAlthough increase in temperatures may boost the number of pathogens, a complex process involving the interaction of a susceptible host, a virulent strain, and environmental factors would influence disease virulence in unpredictable ways. Here we explored if the virulence of an environmentally growing opportunistic fish pathogen,Flavobacterium columnare, would be malleable to evolutionary changes via correlated selection on thermal tolerance. Virulence among the strains increased over years, but tolerance to higher temperatures was associated with reduced virulence. Our results suggest that observed increase in frequency of columnaris epidemics over the last decade is most likely ass…
In Vivo RNA Labeling Using MS2
2014
The trafficking and asymmetric distribution of cytoplasmic RNA is a fundamental process during development and signaling across phyla. Plants support the intercellular trafficking of RNA molecules such as gene transcripts, small RNAs, and viral RNA genomes by targeting these RNA molecules to plasmodesmata (PD). Intercellular transport of RNA molecules through PD has fundamental implications in the cell-to-cell and systemic signaling during plant development and in the systemic spread of viral disease. Recent advances in time-lapse microscopy allow researchers to approach dynamic biological processes at the molecular level in living cells and tissues. These advances include the ability to la…
Response Mechanisms of Invertebrates to Bacillus thuringiensis and Its Pesticidal Proteins
2021
SUMMARY Extensive use of chemical insecticides adversely affects both environment and human health. One of the most popular biological pest control alternatives is bioinsecticides based on Bacillus thuringiensis. This entomopathogenic bacterium produces different protein types which are toxic to several insect, mite, and nematode species. Currently, insecticidal proteins belonging to the Cry and Vip3 groups are widely used to control insect pests both in formulated sprays and in transgenic crops. However, the benefits of B. thuringiensis-based products are threatened by insect resistance evolution. Numerous studies have highlighted that mutations in genes coding for surrogate receptors are …
Colonization of Plant Roots by Pseudomonads and AM Fungi: A Dynamic Phenomenon, Affecting Plant Growth and Health
2008
Because of their enormously large range of plant hosts and role in plant nutrition, arbuscular mycorrhizal (AM) fungi represent an extraordinarily fascinating field of study. Plant growth promotion effects by AM fungi were described as early as 1900 (Sthal 1900) and several data obtained in the second half of the last century support the idea that these microrganisms can act as biocontrol agents (BCA). The extent of root colonization is variable in different plants and under different environmental conditions (Giovannetti and Hepper 1985). Some effects of AM colonization on plants have been reported to be dependent on the degree of root colonization, while others have not. Root exudation an…
Plant defense responses induced by arbuscular mycorrhizal fungi
2002
Plants in their environment daily face many organisms such as fungi, bacteria, mycoplasms, viruses, nematodes, etc. Many of them are potential pathogens; in fact thousands of microorganisms are known to cause plant diseases. Despite this large number of deleterious microorganisms, most of the plants are resistant to their attack since they have developed effective mechanisms to protect themselves.
Tomato and flavour
2008
Part 1: Characterization and Composition of Tomato Plant and Fruit, chapter 5; International audience
Assessment of genetically modified maize 4114 for food and feed uses, under Regulation (EC) No 1829/2003 (application EFSA‐GMO‐NL‐2014‐123)
2018
Abstract Maize 4114 was developed through Agrobacterium tumefaciens‐mediated transformation to provide protection against certain lepidopteran and coleopteran pests by expression of the Cry1F, Cry34Ab1 and Cry35Ab1 proteins derived from Bacillus thuringiensis, and tolerance to the herbicidal active ingredient glufosinate‐ammonium by expression of the PAT protein derived from Streptomyces viridochromogenes. The molecular characterisation data did not identify issues requiring assessment for food/feed safety. None of the compositional, agronomic and phenotypic differences identified between maize 4114 and the non‐genetically modified (GM) comparator(s) required further assessment. There were …
The rhizosphere of mycorrhizal plants
2002
Providing that appropriate carbon substrates are available, microbial communities are able to develop a range of activities which are crucial in maintaining a biological balance in soil (Bowen and Rovira 1999), a key issue for the sustainability of either natural ecosystems or agroecosystems (Kennedy and Smith 1995). Soil-borne microbes have a particular microhabitat in which to flourish. In particular, they are bound to the surface of soil particles or found in soil aggregates, while others interact specifically with the plant root system (Glick 1995). The root-soil interface is actually a dynamic changing environment, a microcosm where microorganisms, plant roots and soil constituents int…
Granulation and microbial community dynamics in the chitosan-supplemented anaerobic treatment of wastewater polluted with organic solvents.
2018
Abstract The effect of chitosan on the development of granular sludge in upflow anaerobic sludge blanket reactors (UASB) when treating wastewater polluted with the organic solvents ethanol, ethyl acetate, and 1-ethoxy-2-propanol was evaluated. Three UASB reactors were operated for 219 days at ambient temperature with an organic loading rate (OLR) of between 0.3 kg COD m −3 d −1 and 20 kg COD m −3 d −1 . One reactor was operated without the addition of chitosan, while the other two were operated with the addition of chitosan doses of 2.4 mg gVSS −1 two times. The three reactors were all able to treat the OLR tested with COD removal efficiencies greater than 90%. However, the time required to…