Plant Pathology (2016) 65, 577-586

N. Mariette, R. Mabon, R. Corbière, F. Boulard, I. Glais, B. Marquer, C. Pasco, J. Montarry and D. Andrivon (2016)
Phenotypic and genotypic changes in French populations of Phytophthora infestans: are invasive clones the most aggressive?
Plant Pathology 65 (4), 577-586
Abstract: The main objective of this investigation was to test the 'always more aggressive' hypothesis, often advocated to explain lineage replacements in clonal populations of the potato late blight oomycete Phytophthora infestans. To this end, genotypic and pathogenicity data on 1274 French isolates of P. infestans, collected over the period 2001–2008, were analysed. Overall, the populations sampled showed limited genetic diversity, with four multilocus lineages (1_A1, 2_A1, 8_A1 and 13_A2) accounting for over 80% of the isolates collected. As in other West European countries, drastic changes in these dominant clonal lineages were observed over the course of the 8 years, particularly in the appearance and propagation of the clone 13_A2. However, invasiveness of clones was not associated with higher aggressiveness; on the contrary, dominant clones had generally low or moderate aggressiveness relative to others present at the same time within the same populations. This finding challenges the link between invasive behaviour and increased aggressiveness often assumed for this biotrophic pathogen, and could reflect the existence of a trade-off between intra-season and inter-season transmission. This would be consistent with the concept of inclusive fitness, which involves the abilities to both reproduce and survive.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Didier Andrivon, Josselin Montarry, Isabelle Glais

Research topic(s) for pests/diseases/weeds:
molecular biology - genes
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Phytophthora infestans	Potato (Solanum tuberosum)	France