The evolution of signaling and monitoring in plant-fungal networks

• 成果类型: Article
• 署名作者: Scott, Thomas W.; Kiers, E. Toby; West, Stuart A.
• 署名单位: University of Oxford; University of St Andrews; Vrije Universiteit Amsterdam
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-9468
• DOI: 10.1073/pnas.2420701122
• 发表日期: 2025-01-28
• 关键词: inclusive fitness; induced resistance; selfish sentinels; kin selection; life-history; alarm calls; COMMUNICATION; COOPERATION; altruism; COMPETITION

摘要

Experiments have shown that when one plant is attacked by a pathogen or herbivore, this can lead to other plants connected to the same mycorrhizal network up- regulating their defense mechanisms. It has been hypothesized that this represents signaling, with attacked plants producing a signal to warn other plants of impending harm. We examined the evolutionary plausibility of this and other hypotheses theoretically. We found that the evolution of plant signaling about an attack requires restrictive conditions, and so will rarely be evolutionarily stable. The problem is that signaling about an attack provides a benefit to competing neighbors, even if they are kin, and so reduces the relative fitness of signaling plants. Indeed, selection is often more likely to push plant behavior in the opposite direction-with plants signaling dishonestly about an attack that has not occurred, or suppressing a cue that they have been attacked. Instead, we show that there are two viable alternatives that could explain the empirical data: 1) the process of being attacked leads to a cue (information about the attack) which is too costly for the attacked plant to fully suppress; 2) mycorrhizal fungi monitor their host plants, detect when they are attacked, and then the fungi signal this information to warn other plants in their network. Our results suggest the empirical work that would be required to distinguish between these possibilities.