アイルランドのジャガイモ飢饉病原体の起源を解明 (Study Points to South America – Not Mexico – as Birthplace of Irish Potato Famine Pathogen)

ad

2025-01-24 ノースカロライナ州立大学 (NCState)

ノースカロライナ州立大学の研究者たちは、ジャガイモ疫病菌(Phytophthora infestans)の起源がメキシコではなく南米アンデス山脈であることを明らかにしました。この研究では、P. infestansとその近縁種である南米固有のPhytophthora andinaやPhytophthora betaceiの全ゲノムを比較し、これら3種が非常に類似していることを発見しました。これにより、P. infestansが南米から北米を経て1840年代にアイルランドに伝播し、ジャガイモ飢饉を引き起こしたと結論付けています。また、アンデス地域が新種分化のホットスポットであることも示唆されています。

<関連情報>

パンゲノム解析から明らかになったPhytophthora infestansと1cクレード種の起源と進化の歴史 A pangenome analysis reveals the center of origin and evolutionary history of Phytophthora infestans and 1c clade species

Allison L. Coomber,Amanda C. Saville,Ignazio Carbone,Michael Martin,Vanessa C. Bieker,Jean Beagle Ristaino

PLOS ONE  Published: January 24, 2025

DOI:https://doi.org/10.1371/journal.pone.0314509

アイルランドのジャガイモ飢饉病原体の起源を解明 (Study Points to South America – Not Mexico – as Birthplace of Irish Potato Famine Pathogen)

Abstract

We examined the evolutionary history of Phytophthora infestans and its close relatives in the 1c clade. We used whole genome sequence data from 69 isolates of Phytophthora species in the 1c clade and conducted a range of genomic analyses including nucleotide diversity evaluation, maximum likelihood trees, network assessment, time to most recent common ancestor and migration analysis. We consistently identified distinct and later divergence of the two Mexican Phytophthora species, P. mirabilis and P. ipomoeae, from P. infestans and other 1c clade species. Phytophthora infestans exhibited more recent divergence from other 1c clade species of Phytophthora from South America, P. andina and P. betacei. Speciation in the 1c clade and evolution of P. infestans occurred in the Andes. P. andina–P. betacei–P. infestans formed a species complex with indistinct species boundaries, hybridizations between the species, and short times to common ancestry. Furthermore, the distinction between modern Mexican and South American P. infestans proved less discrete, suggesting gene flow between populations over time. Admixture analysis indicated a complex relationship among these populations, hinting at potential gene flow across these regions. Historic P. infestans, collected from 1845–1889, were the first to diverge from all other P. infestans populations. Modern South American populations diverged next followed by Mexican populations which showed later ancestry. Both populations were derived from historic P. infestans. Based on the time of divergence of P. infestans from its closest relatives, P. andina and P. betacei in the Andean region, we consider the Andes to be the center of origin of P. infestans, with modern globalization contributing to admixture between P. infestans populations today from Mexico, the Andes and Europe.

1202農芸化学
ad
ad
Follow
ad
タイトルとURLをコピーしました