Genomic signatures of heterokaryosis in the oomycete pathogen Bremia lactucae.
Nat Commun
; 10(1): 2645, 2019 06 14.
Article
en En
| MEDLINE
| ID: mdl-31201315
ABSTRACT
Lettuce downy mildew caused by Bremia lactucae is the most important disease of lettuce globally. This oomycete is highly variable and rapidly overcomes resistance genes and fungicides. The use of multiple read types results in a high-quality, near-chromosome-scale, consensus assembly. Flow cytometry plus resequencing of 30 field isolates, 37 sexual offspring, and 19 asexual derivatives from single multinucleate sporangia demonstrates a high incidence of heterokaryosis in B. lactucae. Heterokaryosis has phenotypic consequences on fitness that may include an increased sporulation rate and qualitative differences in virulence. Therefore, selection should be considered as acting on a population of nuclei within coenocytic mycelia. This provides evolutionary flexibility to the pathogen enabling rapid adaptation to different repertoires of host resistance genes and other challenges. The advantages of asexual persistence of heterokaryons may have been one of the drivers of selection that resulted in the loss of uninucleate zoospores in multiple downy mildews.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Oomicetos
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Enfermedades de las Plantas
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Núcleo Celular
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Lactuca
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Interacciones Huésped-Patógeno
Tipo de estudio:
Qualitative_research
Idioma:
En
Año:
2019
Tipo del documento:
Article