Search results for "weed seed"
showing 7 items of 7 documents
The role of biotic interactions in a prey-predator system : the case of predation and regulation of weed seeds by carabids.
2020
For the transition towards agricultural production systems that are less dependent on herbicides, the use of weed regulation by seed-eating carabids is of great interest. Weed seed predation by carabids is variable and occurs within a complex context of many biotic interactions. This complexity partly explains our current inability to predict levels of in-field weed regulation. In this thesis, I analysed variations in the levels of predation and biological regulation of weeds and determined how they respond to two classes of biotic interactions: 1) the availability of alternative prey; and, 2) intra- and inter-specific interactions between the carabids themselves. Field measurements carried…
Does grassland cover limit the replenishment of weed seed banks during seed rain?
2012
International audience
Species-specific prey choice of carabid beetles in European cereal fields
2017
National audience; Trophic interactions between species in agroecosystems provide key regulation ecosystem services and therefore also determine the dynamics, robustness and resilience of service provision. To achieve international goals of reducing application of pesticides without compromising key provisioning ecosystem services such as crop yield, recent research attaches importance to the biological control potential of carabid beetles. However, apart from feeding on pest species and weed seeds, carabids also consume non-pest prey (alternative prey) such as collembolans and earthworms, which can play a contradictory role in the efficacy of pest and weed control. Most carabids are descri…
Toward a better prediction of in-field weed regulation by carabid beetles in European arable landscapes
2019
International audience; Arable agriculture is still highly reliant on herbicides to manage weeds. As part of the necessary shift towards a reduction in pesticide use, the regulatory effect of seed-eating carabid beetles on weeds has received increasing attention in agroecological research. While strong evidence points to carabids exerting a regulatory effect on certain weed species, it is difficult to predict whether a particular assemblage of carabid species 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. In this paper, we report on specific researc…
The spatial and temporal distribution of carabid and weed seed predation in winter wheat: a comparison between conventional and conservation agricult…
2013
Carabids can be key players in weed seed predation within arable crops under temperate climate. Field management options, because they affect carabid communities, may represent potential levers to increase weed seed predation levels within fields. Among these options, Conservation Agriculture is often presented as a promising management option for carabids but its effect on weed seed predation levels is less clear. In this study, carabids and weed seed predation were monitored using a grid sampling from April till September 2011 in two adjacent winter-wheat fields in North-eastern France, one conducted as no-till with cover crop for 5 years (conservation agriculture) and the other as conven…
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 …
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…