Population genomics supports clonal reproduction and multiple independent gains and losses of parasitic abilities in the most devastating nematode pest
- Others:
- Institut Sophia Agrobiotech (ISA) ; Institut National de la Recherche Agronomique (INRA)-Université Nice Sophia Antipolis (1965 - 2019) (UNS) ; COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)
- Embrapa Recursos Genéticos e Biotecnologia (CENARGEN)
- IPMC ; Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)
- Université Côte d'Azur (UCA)
- Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE) ; Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)
- Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon
- Université de Lyon
- Área de Proteção de Plantas ; Instituto Agronômico do Parana (IAPAR)
- Empresa Brasileira de Pesquisa Agropecuaria; Institut National de la Recherche Agronomique SPE 2016; French National Research Agency (ANR) ANR-13-JSV7-0006-ASEXEVOL; Consorcio Pesquisa Cafe
- European Project: 609398,EC:FP7:PEOPLE,FP7-PEOPLE-2013-COFUND,AGREENSKILLSPLUS(2014)
Description
The root‐knot nematodes are the most devastating worms to worldwide agriculture with Meloidogyne incognita being the most widely distributed and damaging species. This parasitic and ecological success seems surprising given its supposed obligatory clonal reproduction. Clonal reproduction has been suspected based on cytological observations but, so far, never confirmed by population genomics data. As a species, M. incognita is highly polyphagous with thousands of host plants. However, different M. incognita isolates present distinct and overlapping patterns of host compatibilities. Historically, four "host races" had been defined as a function of ranges of compat‐ible and incompatible plants. In this study, we used population genomics to assess whether (a) reproduction is actually clonal in this species, (b) the host races follow an underlying phylogenetic signal or, rather represent multiple independent transitions,and (c) how genome variations associate with other important biological traits such as the affected crops and geographical distribution. We sequenced the genomes of 11 M. incognita isolates across Brazil that covered the four host races in replicates. By aligning the genomic reads of these isolates to the M. incognita reference genomeassembly, we identified point variations. Analysis of linkage disequilibrium and 4‐gametes test showed no evidence for recombination, corroborating the clonal re ‐production of M. incognita. The few point variations between the isolates showed no significant association with the host races, the geographical origin of the samples, or the crop on which they have been collected. Addition of isolates from other locations around the world confirmed this lack of underlying phylogenetic signal. This suggests multiple gains and losses of parasitic abilities and adaptations to different environ‐ments account for the broad host spectrum and wide geographical distribution of M. incognita and thus to its high economic impact. This surprising adaptability without sex poses both evolutionary and agro‐economic challenges.
Additional details
- URL
- https://hal.archives-ouvertes.fr/hal-02444457
- URN
- urn:oai:HAL:hal-02444457v1
- Origin repository
- UNICA