Variations in community assemblages and trophic networks of aphids and parasitoids in protected crops
Abstract Greenhouse crops are thought to be simplified ecosystems because they often consist of monocultures that are relatively isolated from their environment. However, insect pests are still able to colonize these protected crops, which threaten their yields. Similarly, natural enemies of pests m...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Wiley
2020-05-01
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| Series: | Ecosphere |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/ecs2.3126 |
| _version_ | 1818039501456408576 |
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| author | Estelle Postic Anne Le Ralec Christelle Buchard Caroline Granado Yannick Outreman |
| author_facet | Estelle Postic Anne Le Ralec Christelle Buchard Caroline Granado Yannick Outreman |
| author_sort | Estelle Postic |
| collection | DOAJ |
| description | Abstract Greenhouse crops are thought to be simplified ecosystems because they often consist of monocultures that are relatively isolated from their environment. However, insect pests are still able to colonize these protected crops, which threaten their yields. Similarly, natural enemies of pests may be able to colonize greenhouses, providing a form of natural biological pest control. Protected strawberry crops are grown in several types of greenhouses that vary in their degree of openness. Crops often suffer from aphid outbreaks, which can be partly controlled by insect parasitoids immigrating from the surrounding environment. We investigated variations over space and time in both the aphid and parasitoid community diversity and species assemblages associated with protected strawberry crops. We sampled aphids and parasitoids in five regions of France in the spring and summer of two successive years. Despite the relative isolation of these protected crops, we identified a high aphid species richness in them, even at the greenhouse scale. Aphid community composition varied with spatial and temporal factors, but the species assemblages present were mostly determined by local factors. Parasitoid communities were mostly similar among the studied regions, but varied between seasons, with this temporal variation being related to changes in aphid species composition. The study of trophic interactions occurring between aphids and parasitoids allowed the most prevalent and efficient parasitoid species to be identified. The structures of food webs strongly varied in time and space, compromising any prediction of “natural” biological control. We also highlighted ecological factors that can disrupt aphid biological control, such as the occurrence of hyperparasitism or the possibility of apparent mutualism between aphid species. Finally, we showed that the degree of openness of greenhouses influenced both the aphid communities and the hyperparasitism rates in them. These results provide valuable information to improve aphid biological control in protected crops. |
| first_indexed | 2024-12-10T07:59:38Z |
| format | Article |
| id | doaj.art-844806813f944e20a6ab3b5f9345a24a |
| institution | Directory Open Access Journal |
| issn | 2150-8925 |
| language | English |
| last_indexed | 2024-12-10T07:59:38Z |
| publishDate | 2020-05-01 |
| publisher | Wiley |
| record_format | Article |
| series | Ecosphere |
| spelling | doaj.art-844806813f944e20a6ab3b5f9345a24a2022-12-22T01:56:49ZengWileyEcosphere2150-89252020-05-01115n/an/a10.1002/ecs2.3126Variations in community assemblages and trophic networks of aphids and parasitoids in protected cropsEstelle Postic0Anne Le Ralec1Christelle Buchard2Caroline Granado3Yannick Outreman4UMR IGEPP Agrocampus Ouest INRAE Université de Rennes 1 Rennes 35000 FranceUMR IGEPP Agrocampus Ouest INRAE Université de Rennes 1 Rennes 35000 FranceUMR IGEPP Agrocampus Ouest INRAE Université de Rennes 1 Le Rheu 35650 FranceAOPn Fraises de France Estillac 47310 FranceUMR IGEPP Agrocampus Ouest INRAE Université de Rennes 1 Rennes 35000 FranceAbstract Greenhouse crops are thought to be simplified ecosystems because they often consist of monocultures that are relatively isolated from their environment. However, insect pests are still able to colonize these protected crops, which threaten their yields. Similarly, natural enemies of pests may be able to colonize greenhouses, providing a form of natural biological pest control. Protected strawberry crops are grown in several types of greenhouses that vary in their degree of openness. Crops often suffer from aphid outbreaks, which can be partly controlled by insect parasitoids immigrating from the surrounding environment. We investigated variations over space and time in both the aphid and parasitoid community diversity and species assemblages associated with protected strawberry crops. We sampled aphids and parasitoids in five regions of France in the spring and summer of two successive years. Despite the relative isolation of these protected crops, we identified a high aphid species richness in them, even at the greenhouse scale. Aphid community composition varied with spatial and temporal factors, but the species assemblages present were mostly determined by local factors. Parasitoid communities were mostly similar among the studied regions, but varied between seasons, with this temporal variation being related to changes in aphid species composition. The study of trophic interactions occurring between aphids and parasitoids allowed the most prevalent and efficient parasitoid species to be identified. The structures of food webs strongly varied in time and space, compromising any prediction of “natural” biological control. We also highlighted ecological factors that can disrupt aphid biological control, such as the occurrence of hyperparasitism or the possibility of apparent mutualism between aphid species. Finally, we showed that the degree of openness of greenhouses influenced both the aphid communities and the hyperparasitism rates in them. These results provide valuable information to improve aphid biological control in protected crops.https://doi.org/10.1002/ecs2.3126biological controldirect and indirect interactionsinsect pestsnatural enemiesspatiotemporal variationstrawberry crops |
| spellingShingle | Estelle Postic Anne Le Ralec Christelle Buchard Caroline Granado Yannick Outreman Variations in community assemblages and trophic networks of aphids and parasitoids in protected crops Ecosphere biological control direct and indirect interactions insect pests natural enemies spatiotemporal variation strawberry crops |
| title | Variations in community assemblages and trophic networks of aphids and parasitoids in protected crops |
| title_full | Variations in community assemblages and trophic networks of aphids and parasitoids in protected crops |
| title_fullStr | Variations in community assemblages and trophic networks of aphids and parasitoids in protected crops |
| title_full_unstemmed | Variations in community assemblages and trophic networks of aphids and parasitoids in protected crops |
| title_short | Variations in community assemblages and trophic networks of aphids and parasitoids in protected crops |
| title_sort | variations in community assemblages and trophic networks of aphids and parasitoids in protected crops |
| topic | biological control direct and indirect interactions insect pests natural enemies spatiotemporal variation strawberry crops |
| url | https://doi.org/10.1002/ecs2.3126 |
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