Search results for "Tetranychus urticae"
showing 10 items of 16 documents
Mutations in the voltage-gated sodium channel gene associated with deltamethrin resistance in commercially sourced Phytoseiulus persimilis
2020
The implementation of Integrated Pest Management (IPM) in current agricultural practice is a convenient and very effective strategy to maintain pest populations under control. The use of Biological Control Agents, like Phytoseiulus persimilis, is key for the success of such approach. This predatory mite is widely used since it is very effective for controlling the two spotted spider mite (Tetranychus urticae), one of the most devastating pests worldwide. Here we show the identification of mutations located in the Voltage Gated Sodium Channel (VGSC) of P. persimilis, that correlate with the reduced susceptibility to deltamethrin observed in commercially sourced colonies of this predatory mit…
The Odorant-Binding Proteins of the Spider Mite Tetranychus urticae
2021
Spider mites are one of the major agricultural pests, feeding on a large variety of plants. As a contribution to understanding chemical communication in these arthropods, we have characterized a recently discovered class of odorant-binding proteins (OBPs) in Tetranychus urticae. As in other species of Chelicerata, the four OBPs of T. urticae contain six conserved cysteines paired in a pattern (C1–C6, C2–C3, C4–C5) differing from that of insect counterparts (C1–C3, C2–C5, C4–C6). Proteomic analysis uncovered a second family of OBPs, including twelve members that are likely to be unique to T. urticae. A three-dimensional model of TurtOBP1, built on the recent X-ray structure of Varroa destruc…
<p class="Body"><strong>Biological parameters of <em>Neoseiulus longilaterus</em> (Athias-Henriot) (Parasitiformes, Phytoseii…
2019
Tetranychus urticae is the most important pest on different crops worldwide. Search for endemic phytoseiid mites co-occurring with the above pest, which might be good candidates as biocontrol agents, represents the policy followed by most scientists in recent years. The aim of the present work was to assess the various biological and demographic parameters of Neoseiulus longilaterus, associated with T. urticae on weeds, in laboratory conditions using the latter tetranychid and pollen of Oxalis pes-caprae as food. The results showed a better performance of the predator on the prey as regards the postembryonic development (7.63 and 8.18 days for prey and pollen respectively) and the demograph…
First record ofTetranychus ludeniZacher (Acariformes: Tetranychidae) in Italy
2018
Tetranychus ludeni Zacher is reported here for the first time in Italy. It was found on some cultivated and spontaneous plants, often associated with Tetranychus urticae Koch. Four phytoseiid mites, widely distributed in the Mediterranean countries, Phytoseiulus persimilis Athias-Henriot, Iphiseius degenerans Berlese, Typhlodromus (Anthoseius) kerkirae Swirski and Ragusa, and Typhlodromus (Anthoseius) transvaalensis Nesbitt, were found associated with T. ludeni In Sicily. The morphological characters for the identification of the four Italian Tetranychus species are also reported.
Genetic structure of a greenhouse population of the spider mite Tetranychus urticae: spatio-temporal analysis with microsatellite markers.
2002
International audience; The genetic structure of a greenhouse population of the mite Tetranychus urticae was studied by the analysis of five microsatellite loci. Genetic variation was compared during a crop season between periods of population foundation and rapid population increase and was investigated in two consecutive years. The population displayed significant heterozygote deficiency at all the sampling periods. However, inbreeding tended to decrease with increasing density (FIS coefficient between 0.13 and 0.25). No significant genetic differentiation between samples was found either at a spatial scale within the greenhouse or at a temporal scale between two growing seasons (FST betw…
Bioproduction of an extract from Penicillium funiculosum Thom with activity against Ceratitis capitata and Tetranychus urticae
1993
The bioproduction conditions of a crude extract from a strain of Penicillium funiculosum Thom, which shows activity against Ceratitis capitata and Tetranychus urticae, have been optimized. The efficacy degree was 95% (C. capitata) and 100% (T. urticae), according to Abbot. This is the first report on the pesticide activity of an extract from P. funiculosum against these species. The best yields were obtained when P. funiculosum was grown in Raulin-Thom medium at pH 6.5 with sucrose candy as the carbon source and ammonium sulphate and phosphate as the nitrogen source. Other favourable conditions were static cultures, at 28 degrees C, and in the dark.
Effects of a mixture of vegetable and essential oils and fatty acid potassium salts on Tetranychus urticae and Phytoseiulus persimilis.
2008
Laboratory trials were carried out to evaluate the toxicity and the influence of a commercial mixture of vegetal, essential oils, and potassium salts of fatty acids (Acaridoil 13SL) on the population growth rate (r(i)--instantaneous rate of increase) of two mite species, the phytophagous Tetranychus urticae Koch and the predator Phytoseiulus persimilis Athias-Henriot. A residue of 1.3 mg/cm(2) of pesticide solution was harmless for Ph. persimilis eggs, while a moderate mortality of eggs and of larvae from treated eggs of T. urticae, was observed (53.8%). The pesticide also caused a delay in the postembryonic development of the tetranychid. Moreover, 83.4% mortality was reported for treated …
Biological parameters of Neoseiulus longilaterus (Athias-Henriot) (Parasitiformes, Phytoseiidae) fed on prey and pollen in laboratory conditions
2019
Tetranychus urticae is the most important pest on different crops worldwide. Search for endemic phytoseiid mites co-occurring with the above pest, which might be good candidates as biocontrol agents, represents the policy followed by most scientists in recent years. The aim of the present work was to assess the various biological and demographic parameters of Neoseiulus longilaterus, associated with T. urticae on weeds, in laboratory conditions using the latter tetranychid and pollen of Oxalis pes-caprae as food. The results showed a better performance of the predator on the prey as regards the postembryonic development (7.63 and 8.18 days for prey and pollen respectively) and the demograph…
Predatory performance of two Mediterranean phytoseiid species, Typhlodromus laurentii and Typhlodromus rhenanoides fed on eggs of Panonychus citri an…
2013
Laboratory trials were carried out to determine the predatory capacity of two endemic to the Mediterranean area phytoseiid mites Typhlodromus (Typhlodromus) laurentii Ragusa et Swirski and Typhlodromus (Anthoseius) rhenanoides Athias-Henriot (Parasitiformes Phytoseiidae) upon the eggs of the two most important tetranychids damaging Citrus orchards in Sicily: Tetranychus urticae Koch and Panonychus citri (McGregor) (Acariformes Tetranychidae). The research aimed at investigating the predatory behaviour of the phytoseiids upon the prey stage considered the most vulnerable. The predation rate of the two phytoseiid species was different on the two prey eggs, both in every observation day and fo…
Predation of Typhlodromus longilaterus Athias-Henriot (Parasitiformes, Phytoseiidae) females on eggs and juveniles of the tetranychid mites Tetranych…
2013
Typhlodromus longilaterus is a generalist phytoseiid mite described by Athias-Henriot in 1957 and commonly found in Israel on spontaneous herbaceous plants. As very little is known about this species, the present study reports preliminary results on the predation capacity of phytoseiid females on eggs and juveniles of two tetranychid mites very common in the Mediterranean area, Tetranychus urticae and Panonychus citri. After 24 hours the phytoseiid females preyed on 15% of offered eggs of both tetranychids, while the prey ratio was higher on T. urticae eggs after this period (33.4% and 33.5% vs 20.8% and 16.2% after 2 and 3 days for T. urticae and P. citri respectively). The phytoseiid show…