Search results for "beetle"

Toward a better understanding of in-field weed regulation by carabid beetles, and their functional characteristics, in European arable landscapes

2019

For future arable agriculture, there is a need for more sustainable methods to manage weeds that are less reliant on herbicides and maintain food production. Control of weeds by natural enemies is an agro-ecological alternative to reduce the use of herbicides. While strong evidence points to carabid beetles exerting a regulatory effect on certain weed species, it is difficult to predict whether a particular assemblage of carabid species or functional groups will drive the function of weed seed predation in field conditions. There are also uncertainties about which key local and landscape-scale factors affect the function of weed seed predation, and the functional characteristics of carabid …

Genetic variation in growth and development time under two selection regimes in Leptinotarsa decemlineata

2008

It is possible to predict the potential range of a species on the basis of its ecological characteristics and those of the invaded ecosystem. The existence of genetic variation indicates a species' potential to respond to new environmental conditions, thus facilitating its success as an invader. Accordingly, evolutionary and ecological approaches are needed to identify the factors explaining both species' range and their potential to invade new areas. We combined these two approaches and studied whether genetic variation in life-history traits under abiotic (temperature) and biotic (host plant) selection pressures contributes to the potential range expansion of Leptinotarsa decemlineata Say…

Do properties and species of weed seeds affect their consumption by carabid beetles?

2019

International audience; Seed predators are an integral part of agroecosystems, where they can reduce the populations of weeds. The preference of predators for seeds and the observed predation rate may be affected by the properties of seeds (e.g. taxonomy, chemical composition, physical defence). In this work, we focused on seed consumption of Taraxacum officinale Web. and Stellaria media (L.) Vill., from France and the Czech Republic, by three species of ground beetle that are seed predators (Coleoptera: Carabidae): Poecilus cupreus (L.), Pterostichus melanarius (Illiger) and Anchomenus dorsalis (Pontoppidan). The seed species were offered in arenas, simultaneously, under three different ex…

Effects of a glyphosate-based herbicide on survival and oxidative status of a non-target herbivore, the Colorado potato beetle (Leptinotarsa decemlin…

2018

Abstract Glyphosate is the globally most used herbicide against a wide range of weeds. Glyphosate has been considered safe to animals as it mainly targets physiological pathways in plants. However, recent toxicological studies have revealed that glyphosate can cause various toxic effects also on animals. In this study, we investigated the direct toxic effects of a glyphosate-based herbicide (GBH, Roundup® Bio) on 1) survival and 2) oxidative status of a non-target herbivore by using Colorado potato beetles (Leptinotarsa decemlineata), originating from Poland and USA, as model species. Larvae were randomly divided into three groups: 1) high concentration (100% Roundup Bio, 360 g/l), 2) low c…

Redescription of the forgotten New Caledonian weevil genus

2018

Abstract Callistomorphus is one of the “forgotten” genera of the tribe Eugnomini inhabiting rain forest in New Caledonia. In this paper, the genus Callistomorphus and the type species C.farinosus are redescribed. Eight new species, Callistomorphusfundatussp. n., C.gibbussp. n., C.malleussp. n., C.minimussp. n., C.rutaisp. n., C.szoltysisp. n., C.torosussp. n. and C.turbidussp. n., are described, originating from the main island of New Caledonia. Illustrations and SEM photographs of the external morphology and the male and female terminalia are provided, as well as dorsal habitus colour photographs of the adults, a key to the species, a distribution map, and a discussion of the systematic po…

A cost of maternal care in the dung beetle Onthophagus taurus?

2002

Parental care theory assumes that investment in current offspring will trade against future investment. A number of field studies on birds have used clutch size manipulations to demonstrate a survival cost to chick rearing. However, such studies do not account for costs accrued during earlier stages of reproduction because not all aspects of reproductive effort are manipulated by varying the number of nestlings. In this study, we investigate the effect of reproductive effort on female survival in the dung beetle, Onthophagus taurus. By experimentally manipulating mating status and dung availability, we demonstrate that virgin females survive longer than mated females and that the survival o…

Effects of forest restoration treatments on the abundance of bark beetles in Norway spruce forests of southern Finland

2009

Abstract Restoration of protected areas in boreal forests frequently includes creating substantial volumes of dead wood. While this benefits a wide range of dead wood dependent invertebrate species, some of these are regarded as forest pests. Therefore, the risk of elevated levels of tree mortality in surrounding commercial forests must be considered. In a large-scale field experiment in southern Finland, we studied the effects of restoration treatments on the abundance of bark beetles within and in the vicinity of restored areas, in particular focusing on Ips typographus and Pityogenes chalcographus . The treatments applied to managed Norway spruce forests were controlled burning and parti…

Insects and fungi: ecological interactions and functional biodiversity

Data from: Ancient symbiosis confers desiccation resistance to stored grain pest beetles

2017

Microbial symbionts of insects provide a range of ecological traits to their hosts that are beneficial in the context of biotic interactions. However, little is known about insect symbiont-mediated adaptation to the abiotic environment, e.g. temperature and humidity. Here we report on an ancient clade of intracellular, bacteriome-located Bacteroidetes symbionts that are associated with grain and wood pest beetles of the phylogenetically distant families Silvanidae and Bostrichidae. In the saw-toothed grain beetle Oryzaephilus surinamensis, we demonstrate that the symbionts affect cuticle thickness, melanization and hydrocarbon profile, enhancing desiccation resistance and thereby strongly i…

Odorants of Capsicum spp. Dried Fruits as Candidate Attractants for Lasioderma serricorne F. (Coleoptera: Anobiidae)

2021

The cigarette beetle, Lasioderma serricorne F. (Coleoptera: Anobiidae) is an important food storage pest affecting the tobacco industry and is increasingly impacting museums and herbaria. Monitoring methods make use of pheromone traps which can be implemented using chili fruit powder. The objective of this study was to assess the response of L. serricorne to the volatile organic compounds (VOCs) from different chili powders in order to identify the main semiochemicals involved in this attraction. Volatiles emitted by Capsicum annuum, C. frutescens, and C. chinense dried fruit powders were tested in an olfactometer and collected and analyzed using SPME and GC-MS. Results indicated that C. an…