Publicação
Temporal dynamics of endophytic microbial communities colonizing olives infested and non-infested by olive fruit fly
| Resumo: | Olive fruit fly, Bactrocera oleae (Rossi) (Diptera: Tephritidae) is the major insect pest of olive crop worldwide. Distinct olive cultivars exhibit different susceptibility to olive fruit fly infestation and the causes of this phenomenon are still unclear. Here, we wanted to disclose the role of biotic and abiotic factors in shaping the olive-associated endophytes and their implication in conferring different host susceptibilities to olive fly. The importance of air as a source of endophytes was additionally evaluated. Accordingly, the endophytic microbial composition of infested and non-infested fruits from cultivars Madural (susceptible to olive fly) and Cobrançosa (less susceptible) were studied over two maturation indexes in two olive orchards under organic and integrated management. Endophytic diversity assessed by rRNA sequencing of cultivable isolates revealed a larger consortium of bacteria associated to olives than fungi. The bacterial communities were predominantly composed of Proteobacteria and Actinobacteria while the fungal community was dominated by members belonging to Ascomycota. The overall assemblages of endophytes in fruits were shaped mainly by the maturation index, followed by the type of management and cultivar, being the level of infestation a negligible effect. Despite this, it was found a clear positive association of a set of endophytes with the resistant cultivar (Pseudomonas citronellolis, Rhodococcus fascians, Actinobacterium sp., Cladosporium sp. 2, Stereum sp. and Aspergillus flavus), organic orchard and non-infested fruits (Microbacterium paraoxydans, Kocuria sp., Penicillium solitum, Cladosporium sp3. and Vishniacozyma victoriae). The microbial composition of the air and the fruit endosphere were completely different, suggesting that there are other sources of endophytes. Our study provides potential microbial candidates to further evaluate their role on host cultivar susceptibility/resistance to fruit fly. |
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| Autores principais: | Lopes, Teresa |
| Assunto: | Bactrocera oleae Rossi Susceptibility of olive cultivars Endophytes Orchard management Maturation index Airborne microorganisms |
| Ano: | 2020 |
| País: | Portugal |
| Tipo de documento: | dissertação de mestrado |
| Tipo de acesso: | acesso restrito |
| Instituição associada: | Instituto Politécnico de Bragança |
| Idioma: | inglês |
| Origem: | Biblioteca Digital do IPB |
| Resumo: | Olive fruit fly, Bactrocera oleae (Rossi) (Diptera: Tephritidae) is the major insect pest of olive crop worldwide. Distinct olive cultivars exhibit different susceptibility to olive fruit fly infestation and the causes of this phenomenon are still unclear. Here, we wanted to disclose the role of biotic and abiotic factors in shaping the olive-associated endophytes and their implication in conferring different host susceptibilities to olive fly. The importance of air as a source of endophytes was additionally evaluated. Accordingly, the endophytic microbial composition of infested and non-infested fruits from cultivars Madural (susceptible to olive fly) and Cobrançosa (less susceptible) were studied over two maturation indexes in two olive orchards under organic and integrated management. Endophytic diversity assessed by rRNA sequencing of cultivable isolates revealed a larger consortium of bacteria associated to olives than fungi. The bacterial communities were predominantly composed of Proteobacteria and Actinobacteria while the fungal community was dominated by members belonging to Ascomycota. The overall assemblages of endophytes in fruits were shaped mainly by the maturation index, followed by the type of management and cultivar, being the level of infestation a negligible effect. Despite this, it was found a clear positive association of a set of endophytes with the resistant cultivar (Pseudomonas citronellolis, Rhodococcus fascians, Actinobacterium sp., Cladosporium sp. 2, Stereum sp. and Aspergillus flavus), organic orchard and non-infested fruits (Microbacterium paraoxydans, Kocuria sp., Penicillium solitum, Cladosporium sp3. and Vishniacozyma victoriae). The microbial composition of the air and the fruit endosphere were completely different, suggesting that there are other sources of endophytes. Our study provides potential microbial candidates to further evaluate their role on host cultivar susceptibility/resistance to fruit fly. |
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