植物宿主-病原体メタポピュレーションにおける毒性の進化
Peter H Thrall1, Jeremy J Burdon
1Commonwealth Scientific and Industrial Research Organization (CSIRO)-Plant Industry, Centre for Plant Biodiversity Research, General Post Office Box 1600, Canberra, ACT 2601, Australia. Peter.Thrall@csiro.au
Science (New York, N.Y.)
|March 15, 2003
まとめ
野生の麻と生の病原体集団では,病原体の毒性と宿主耐性が局所的に異なっていた. 選択は宿主耐性に基づく異なる病原菌株を好み,これは遺伝子対遺伝子の共進化モデルと一致する.
科学分野:
- エコロジー エコロジー エコロジー
- 進化生物学の進化生物学について
- 植物病理学 植物病理学
背景:
- 野生の植物と病原体の相互作用は,生態系の動態にとって極めて重要です.
- ホストの耐性や病原体の毒性の局所的な適応は一般的です.
- 遺伝子対遺伝子の相互作用は,共進化を理解するための重要なモデルである.
研究 の 目的:
- 自然システムにおける宿主耐性と病原体の毒性の関係を調査する.
- 病原菌株の空間的分布パターンを決定する.
- 遺伝子対遺伝子の共進化モデルの予測をテストする.
主な方法:
- 地元住民の宿主耐性および病原体の毒性のフィールド調査.
- 病原体の適性を評価するための実験的ワクチン接種.トレードオフ.
- 病原菌株の空間的分布と時間的安定性の分析.
主要な成果:
- 集団間の宿主耐性および病原体毒性の有意な変動.
- 高い宿主耐性と頻繁に発生する広範囲にわたる毒性の病原体との相関.
- 病原体胞子生産と毒性の間の負のトレードオフの証拠.
- 病原体の非ランダムな空間分布は,強力な局所的選択を示唆する.
結論:
- 選択は,耐性宿主集団における毒性の高い病原体と,感受性の高い集団における毒性の高い菌株を好む.
- トレードオフは,遺伝的多様性を維持し,病原体の毒性が宿主耐性を超えるのを防ぐために不可欠です.
- 発見は,自然系における宿主-病原体共進化の遺伝子対遺伝子モデルを裏付けている.
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