11 research outputs found
Evaluation of pesticide residues in wheat grains and its products from Algeria
Get PDFThe presence of pesticide residues in wheat grains and its products produced and imported in Algeria was determined using QuEchERS extraction method and multi-residue analysis by gas chromatography–mass spectrometry. Among the 80 wheat samples analysed, detectable residues were found in 62.5% of samples. The most often pesticide found was pirimiphos methyl in 46 samples (57.5%). A percentage of 5% of samples contained pesticide residues above Maximum Residue Limits (MRLs) due to benalaxyl, chlorpyrifos and metalaxyl residues. Risk assessment for long-term exposure was done for all pesticides detected in wheat grains, the risk of exposure of Algerian consumers to pirimiphos methyl residues through wheat consumption was potentially high (EDI = 78%ADI). This risk was less important in the case of chlorpyrifos (EDI<9% ADI). For the others residues, EDIs were less than 1.5% of ADIs
Dual biocontrol potential of the entomopathogenic fungus Akanthomyces muscarius against Thaumetopoea pityocampa and plant pathogenic fungi
Get PDFAkanthomyces spp. species are known for their capacity to biocontrol of certain insects and plant pathogens;
however, their ability to biocontrol the pine processionary (Thaumetopoea pityocampa) and certain
phytopathogenic fungi belonging to the genera Fusarium and Curvularia have not been studied before. In
this study, a strain from Akanthomyces muscarius was isolated from wheat grains and then identified by
morphological and molecular tests. The strain was further studied for its capacity to control
Thaumetopoea pityocampa larvae through dose-mortality tests, and its ability to control some phytopathogenic
fungi strains of the genera Fusarium and Curvularia was studied through direct confrontation
tests. Dose-mortality tests at three concentrations of Akanthomyces muscarius against the first
instar larvae revealed a mortality of 92.15% after 11 days for the concentration of 2.3 106 conidia.
ml 1, with a median lethal concentration of 7.6 x103 conidia.ml1. Our isolate also showed antifungal
activity against these phytopathogenic fungi with inhibition rates ranging from 39.61% to 52.94%.
Akanthomyces muscarius proved to be a promising biocontrol agent for plant pests and diseases.
2023 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access
article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
Investigating the spread of Pseudomonas savastanoi pv. savastanoi the causal agent of Olive knot disease in Algeria
Get PDFOlive knot disease is one of the most important diseases affecting olive cultivation, and Pseudomonas savastanoi pv. savastanoi is recognised as its causal agent. The aim of our research is to explore the reasons behind the alarming spread of olive knot disease in Algeria for the regions of Bouira, Bejaia and Tizi-ouzou and to study the factors implicated on its infestation. Field surveys were carried out during the period 2019-2020 in several olive orchards in the Kabylie area on the northern tip of Algeria. The isolation of P. savastanoi was carried out on King-B medium from the sampled knots, the identification of the pathogen was done by biochemical, biological and molecular methods. The field survey revealed a heterogeneous distribution of the disease depending on the site. However, all varieties of Olea europea grown in the study area were affected regardless of the age of the tree. A total of 14 bacterial strains were isolated from knots on semi-selective medium (King B) and identified as P. savastanoi based on biochemical characteristics (LOPAT test), and phyto pathogenicity test on olive plants.The amplification of the iaaL gene confirmed that the selected strains concernP. savastanoi. The biochemical characterisation of the bacteria associated with olive knots found alone or in association with P. savastanoi revealed the identification of mainly Pantoa, to which were added Stenotrophomonas, Rahnella, Seratia,Pseudomonasfluorescens, Enterobacter cloacae and Citrobacter freundi. These associated bacteria would appear to contribute to the virulence of the causal agent and/or have antagonistic activity that may depreciate the disease
Investigating the spread of Pseudomonas savastanoi pv. savastanoi the causal agent of Olive knot disease in Algeria
Get PDFOlive knot disease is one of the most important diseases affecting olive cultivation, and Pseudomonas savastanoi pv. savastanoi is recognised as its causal agent. The aim of our research is to explore the reasons behind the alarming spread of olive knot disease in Algeria for the regions of Bouira, Bejaia and Tizi-ouzou and to study the factors implicated on its infestation. Field surveys were carried out during the period 2019-2020 in several olive orchards in the Kabylie area on the northern tip of Algeria. The isolation of P. savastanoi was carried out on King-B medium from the sampled knots, the identification of the pathogen was done by biochemical, biological and molecular methods. The field survey revealed a heterogeneous distribution of the disease depending on the site. However, all varieties of Olea europea grown in the study area were affected regardless of the age of the tree. A total of 14 bacterial strains were isolated from knots on semi-selective medium (King B) and identified as P. savastanoi based on biochemical characteristics (LOPAT test), and phyto pathogenicity test on olive plants.The amplification of the iaaL gene confirmed that the selected strains concernP. savastanoi. The biochemical characterisation of the bacteria associated with olive knots found alone or in association with P. savastanoi revealed the identification of mainly Pantoa, to which were added Stenotrophomonas, Rahnella, Seratia,Pseudomonasfluorescens, Enterobacter cloacae and Citrobacter freundi. These associated bacteria would appear to contribute to the virulence of the causal agent and/or have antagonistic activity that may depreciate the disease
Evaluation of pesticide residues in fruits and vegetables from Algeria
No full textA total of 160 samples of 13 types of fresh fruits and vegetables from domestic production and
import were analysed to detect the presence of pesticide residues. Analysis was performed by
multi-residual extraction followed by gas chromatography–mass spectrometry. In 42.5% of the
tested samples, no residues were found and 12.5% of samples contained pesticide residues above
maximum residue limits. Risk assessment for long-term exposure was done for all pesticides
detected in this study. Except chlorpyrifos and lambda-cyhalothrin, exposure to pesticides from
vegetables and fruits was below 1% of the acceptable daily intake. Short-term exposure assessment
revealed that in seven pesticide/commodity combinations, including three pesticides
(chlorpyrifos, deltamethrin and lambda-cyhalothrin), the acute reference dose had been exceeded
Dual biocontrol potential of the entomopathogenic fungus Akanthomyces muscarius against Thaumetopoea pityocampa and plant pathogenic fungi
Get PDFEvaluation of pesticide residues in fruits and vegetables from Algeria Part B Surveillance
Get PDFA total of 160 samples of 13 types of fresh fruits and vegetables from domestic production and import were analysed to detect the presence of pesticide residues. Analysis was performed by multi-residual extraction followed by gas chromatography–mass spectrometry. In 42.5% of the tested samples, no residues were found and 12.5% of samples contained pesticide residues above maximum residue limits. Risk assessment for long-term exposure was done for all pesticides detected in this study. Except chlorpyrifos and lambda-cyhalothrin, exposure to pesticides from vegetables and fruits was below 1% of the acceptable daily intake. Short-term exposure assessment revealed that in seven pesticide/commodity combinations, including three pesticides (chlorpyrifos, deltamethrin and lambda-cyhalothrin), the acute reference dose had been exceeded
Evaluation of pesticide residues in fruits and vegetables from Algeria
Get PDFA total of 160 samples of 13 types of fresh fruits and vegetables from domestic production and import were analysed to detect the presence of pesticide residues. Analysis was performed by multi-residual extraction followed by gas chromatography–mass spectrometry. In 42.5% of the tested samples, no residues were found and 12.5% of samples contained pesticide residues above maximum residue limits. Risk assessment for long-term exposure was done for all pesticides detected in this study. Except chlorpyrifos and lambda-cyhalothrin, exposure to pesticides from vegetables and fruits was below 1% of the acceptable daily intake. Short-term exposure assessment revealed that in seven pesticide/commodity combinations, including three pesticides
(chlorpyrifos, deltamethrin and lambda-cyhalothrin), the acute reference dose had been exceeded
