John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK.
University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
Commun Biol. 2021 Oct 22;4(1):1216. doi: 10.1038/s42003-021-02747-1.
Fungi have evolved an array of spore discharge and dispersal processes. Here, we developed a theoretical model that explains the ejection mechanics of aeciospore liberation in the stem rust pathogen Puccinia graminis. Aeciospores are released from cluster cups formed on its Berberis host, spreading early-season inoculum into neighboring small-grain crops. Our model illustrates that during dew or rainfall, changes in aeciospore turgidity exerts substantial force on neighboring aeciospores in cluster cups whilst gaps between spores become perfused with water. This perfusion coats aeciospores with a lubrication film that facilitates expulsion, with single aeciospores reaching speeds of 0.053 to 0.754 m·s. We also used aeciospore source strength estimates to simulate the aeciospore dispersal gradient and incorporated this into a publicly available web interface. This aids farmers and legislators to assess current local risk of dispersal and facilitates development of sophisticated epidemiological models to potentially curtail stem rust epidemics originating on Berberis.
真菌已经进化出了一系列孢子排放和散布的过程。在这里，我们开发了一个理论模型，解释了柄锈菌病原体小麦秆锈菌中分生孢子释放的力学机制。分生孢子从其小檗宿主上形成的簇杯中释放出来，将早期季节的接种体传播到邻近的小粒作物中。我们的模型表明，在露水或降雨期间，分生孢子的膨胀会对簇杯中相邻的分生孢子施加很大的力，而孢子之间的间隙则会充满水。这种渗透在分生孢子上形成了一层润滑膜，有助于其排出，单个分生孢子的速度可达 0.053 到 0.754 m·s。我们还使用分生孢子源强度估计来模拟分生孢子的散布梯度，并将其纳入一个公开的网络界面。这有助于农民和立法者评估当前当地的散布风险，并促进复杂的流行病学模型的开发，以潜在地遏制起源于小檗的小麦秆锈病流行。
