Estimating gene flow between refuges and crops: a case study of the biological control of Eriosoma lanigerum by Aphelinus mali in apple orchards.
Parasitoid disturbance populations in agroecosystems can be maintained through the provision of habitat refuges with host resources. However, specialized herbivores that feed on different host plants have been shown to form host-specialized races. Parasitoids may subsequently specialize on these her...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Public Library of Science (PLoS)
2011-01-01
|
| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC3206839?pdf=render |
| _version_ | 1818284362308780032 |
|---|---|
| author | Blas Lavandero Christian C Figueroa Pierre Franck Angela Mendez |
| author_facet | Blas Lavandero Christian C Figueroa Pierre Franck Angela Mendez |
| author_sort | Blas Lavandero |
| collection | DOAJ |
| description | Parasitoid disturbance populations in agroecosystems can be maintained through the provision of habitat refuges with host resources. However, specialized herbivores that feed on different host plants have been shown to form host-specialized races. Parasitoids may subsequently specialize on these herbivore host races and therefore prefer parasitizing insects from the refuge, avoiding foraging on the crop. Evidence is therefore required that parasitoids are able to move between the refuge and the crop and that the refuge is a source of parasitoids, without being an important source of herbivore pests. A North-South transect trough the Chilean Central Valley was sampled, including apple orchards and surrounding Pyracantha coccinea (M. Roem) (Rosales: Rosacea) hedges that were host of Eriosoma lanigerum (Hemiptera: Aphididae), a globally important aphid pest of cultivated apples. At each orchard, aphid colonies were collected and taken back to the laboratory to sample the emerging hymenopteran parasitoid Aphelinus mali (Hymenoptera: Aphelinidae). Aphid and parasitoid individuals were genotyped using species-specific microsatellite loci and genetic variability was assessed. By studying genetic variation, natural geographic barriers of the aphid pest became evident and some evidence for incipient host-plant specialization was found. However, this had no effect on the population-genetic features of its most important parasitoid. In conclusion, the lack of genetic differentiation among the parasitoids suggests the existence of a single large and panmictic population, which could parasite aphids on apple orchards and on P. coccinea hedges. The latter could thus comprise a suitable and putative refuge for parasitoids, which could be used to increase the effectiveness of biological control. Moreover, the strong geographical differentiation of the aphid suggests local reinfestations occur mainly from other apple orchards with only low reinfestation from P. cocinnea hedges. Finally, we propose that the putative refuge could act as a source of parasitoids without being a major source of aphids. |
| first_indexed | 2024-12-13T00:51:36Z |
| format | Article |
| id | doaj.art-ad4da708062142f1a9871dd976908293 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-13T00:51:36Z |
| publishDate | 2011-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-ad4da708062142f1a9871dd9769082932022-12-22T00:04:54ZengPublic Library of Science (PLoS)PLoS ONE1932-62032011-01-01611e2669410.1371/journal.pone.0026694Estimating gene flow between refuges and crops: a case study of the biological control of Eriosoma lanigerum by Aphelinus mali in apple orchards.Blas LavanderoChristian C FigueroaPierre FranckAngela MendezParasitoid disturbance populations in agroecosystems can be maintained through the provision of habitat refuges with host resources. However, specialized herbivores that feed on different host plants have been shown to form host-specialized races. Parasitoids may subsequently specialize on these herbivore host races and therefore prefer parasitizing insects from the refuge, avoiding foraging on the crop. Evidence is therefore required that parasitoids are able to move between the refuge and the crop and that the refuge is a source of parasitoids, without being an important source of herbivore pests. A North-South transect trough the Chilean Central Valley was sampled, including apple orchards and surrounding Pyracantha coccinea (M. Roem) (Rosales: Rosacea) hedges that were host of Eriosoma lanigerum (Hemiptera: Aphididae), a globally important aphid pest of cultivated apples. At each orchard, aphid colonies were collected and taken back to the laboratory to sample the emerging hymenopteran parasitoid Aphelinus mali (Hymenoptera: Aphelinidae). Aphid and parasitoid individuals were genotyped using species-specific microsatellite loci and genetic variability was assessed. By studying genetic variation, natural geographic barriers of the aphid pest became evident and some evidence for incipient host-plant specialization was found. However, this had no effect on the population-genetic features of its most important parasitoid. In conclusion, the lack of genetic differentiation among the parasitoids suggests the existence of a single large and panmictic population, which could parasite aphids on apple orchards and on P. coccinea hedges. The latter could thus comprise a suitable and putative refuge for parasitoids, which could be used to increase the effectiveness of biological control. Moreover, the strong geographical differentiation of the aphid suggests local reinfestations occur mainly from other apple orchards with only low reinfestation from P. cocinnea hedges. Finally, we propose that the putative refuge could act as a source of parasitoids without being a major source of aphids.http://europepmc.org/articles/PMC3206839?pdf=render |
| spellingShingle | Blas Lavandero Christian C Figueroa Pierre Franck Angela Mendez Estimating gene flow between refuges and crops: a case study of the biological control of Eriosoma lanigerum by Aphelinus mali in apple orchards. PLoS ONE |
| title | Estimating gene flow between refuges and crops: a case study of the biological control of Eriosoma lanigerum by Aphelinus mali in apple orchards. |
| title_full | Estimating gene flow between refuges and crops: a case study of the biological control of Eriosoma lanigerum by Aphelinus mali in apple orchards. |
| title_fullStr | Estimating gene flow between refuges and crops: a case study of the biological control of Eriosoma lanigerum by Aphelinus mali in apple orchards. |
| title_full_unstemmed | Estimating gene flow between refuges and crops: a case study of the biological control of Eriosoma lanigerum by Aphelinus mali in apple orchards. |
| title_short | Estimating gene flow between refuges and crops: a case study of the biological control of Eriosoma lanigerum by Aphelinus mali in apple orchards. |
| title_sort | estimating gene flow between refuges and crops a case study of the biological control of eriosoma lanigerum by aphelinus mali in apple orchards |
| url | http://europepmc.org/articles/PMC3206839?pdf=render |
| work_keys_str_mv | AT blaslavandero estimatinggeneflowbetweenrefugesandcropsacasestudyofthebiologicalcontroloferiosomalanigerumbyaphelinusmaliinappleorchards AT christiancfigueroa estimatinggeneflowbetweenrefugesandcropsacasestudyofthebiologicalcontroloferiosomalanigerumbyaphelinusmaliinappleorchards AT pierrefranck estimatinggeneflowbetweenrefugesandcropsacasestudyofthebiologicalcontroloferiosomalanigerumbyaphelinusmaliinappleorchards AT angelamendez estimatinggeneflowbetweenrefugesandcropsacasestudyofthebiologicalcontroloferiosomalanigerumbyaphelinusmaliinappleorchards |