Search results for "Insect Science"
showing 10 items of 1011 documents
Immunocompetence increases with larval body size in a phytophagous moth
2013
Despite the obvious benefit of an immune system, its efficacy against pathogens and parasites may show great variation among individuals, populations and species. Understanding the causes of this variation is becoming a central theme in ecology. Many biotic and abiotic factors are known to influence immunocompetence (temperature, age, etc.). However, for a given age, size among individuals varies, probably as a result of accumulated resources. Thus, these variable resources could be allocated to immune defence and, consequently, body size may explain part of the variation in immune responsiveness. However, the influence of body size on immune defence is often overlooked. The present study i…
New records of phytoseiid mites from Italy, with description of a new species and a redescription of other two (Parasitiformes, Phytoseiidae)
2020
The Italian phytoseiid fauna consists of 91 valid species. Eighteen of them were described as new species from materials collected in various Italian localities. In the present paper we report nine new records from the Italian fauna and describe the new species, Neoseiulus mediterraneus belonging to the subfamily Amblyseiinae. Complementary descriptions of two rare species, namely: Typhlodromus (Anthoseius) singularis and Typhlodromus (Typhlodromus) knisleyi, were also added.
Tomato trichomes are deadly hurdles limiting the establishment of Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae)
2021
[EN] Amblyseius swirskii is a predatory mite widely used for the control of very important pest species, such as whiteflies and thrips, in organic farming and conventional agriculture. However, this species cannot establish on tomato crops, probably due to the toxic effects of plant trichomes and their exudates. We evaluated tomato plants for effects on: a) A. swirskii preference mediated by plant volatiles, b) A. swirskii development, predation capacity and reproductive performance, c) the dispersal and survival of mites as affected by stem trichomes, and d) mite survival as a function of secondary metabolites secreted by tomato trichomes. The results showed that A. swirskii mites which ga…
<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.
On the identity of Neoseiulus fallacis (Garman 1948) (Parasitiformes, Phytoseiidae): redescription of the species and description of the new species …
2016
ABSTRACTNeoseiulus fallacis (Garman) is a broadly commercialised phytoseiid mite used in Integrated Pest Management (IPM) programmes especially in northern and southern America. However, its taxonomic status was, until now, equivocal because no redescription based on type material had ever been made. The authors redescribe N. fallacis from type material in Garman’s collection, designating the lectotype and paralectotypes for the species. Moreover, a new species of the fallacis complex, discovered among the fallacis type material, is described and named N. garmani sp. nov. in honour of Philip Garman.
Phytoseiid mites from Basilicata region (Southern Italy): species diversity, redescription of Typhloseiulus arzakanicus Arutunjan and a dichotomic ke…
2017
A survey of phytoseiid mites was carried out in the Basilicata region (Southern Italy) between 1976 and 2014 on wild and cultivated plants. A total of 38 species belonging to eleven genera and two subgenera were found on 59 plant species. The most common species was Euseius finlandicus (Oudemans) (39%) followed by Typhlodromus (Typhlodromus) exhilaratus Ragusa (32.2%), Kampimodromus aberrans (Oudemans) (27.1%), Typhlodromus (Anthoseius) cryptus (Athias-Henriot) (23.7%). Typhloseiulus arzakanicus (Arutunjan), found for first time in Italy, is redescribed here, while the male of this species is described for the first time. A dichotomic key of the species belonging to the genus Typhloseiulus …
Resource profitability, but not caffeine, affects individual and collective foraging in the stingless beePlebeia droryana
2019
ABSTRACT Plants and pollinators form beneficial relationships, with plants offering resources in return for pollination services. Some plants, however, add compounds to nectar to manipulate pollinators. Caffeine is a secondary plant metabolite found in some nectars that affects foraging in pollinators. In honeybees, caffeine increases foraging and recruitment to mediocre food sources, which might benefit the plant, but potentially harms the colonies. For the largest group of social bees, the stingless bees, the effect of caffeine on foraging behaviour has not been tested yet, despite their importance for tropical ecosystems. More generally, recruitment and foraging dynamics are not well und…
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…
Modeling Environmental Influences in the Psyllaephagus bliteus (Hymenoptera: Encyrtidae)-Glycaspis brimblecombei (Hemiptera: Aphalaridae) Parasitoid-…
2017
Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae) is an invasive psyllid introduced into the Mediterranean area, where it affects several species of Eucalyptus. Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae) is a specialized parasitoid of this psyllid that was accidentally introduced into Italy in 2011. We developed a model of this host–parasitoid system that accounts for the influence of environmental conditions on the G. brimblecombei population dynamics and P. bliteus parasitism rates in the natural ecosystem. The Lotka–Volterra-based model predicts non-constant host growth and parasitoid mortality rates in association with variation in environmental conditions. The model was …