Host-specificity of AM fungal population growth rates can generate feedback on plant growth
Host-specificity of AM fungal population growth rates can generate feedback on plant growth
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DOI：
10.1023/a:1020221609080
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发表时间：
2002-07-01
期刊：
影响因子：
4.9
通讯作者：
Bever, JD
中科院分区：
文献类型：
--
作者：
Bever, JD
虽然植物和AM真菌之间的互利互动是生态系统过程中的重要性显而易见，这种互动中的生态和进化动力学的影响因素知之甚少。植物和AM真菌的相对生长速率的相互依赖可能会产生复杂的动态，其中AM真菌群落的组成的变化，由于与主机和真菌组成的这种变化，然后差异反馈植物生长。我首先回顾反馈动力学的证据，然后提出一种方法来评估这种复杂的动态。我特别提出的证据表明，特定的主机在AM真菌的人口增长率的差异。混合AM真菌的纯培养物以产生初始真菌群落。然后将该群落分布到复制盆中，并与四种共存植物种之一一起生长。AM真菌孢子在不同的寄主上产生不同的组成。然后将AM真菌群落接种回它们自己的宿主物种并生长第二个生长季节。在第一代中观察到的分化在第二代中得到增强，验证了孢子组成的测量反映了AM真菌种群生长速率的宿主特异性差异。在对这个系统的进一步研究中，我通过两对植物物种发现了负反馈的证据。AM真菌群落内的动态从而有助于植物物种的共存。
While the mutualistic interaction between plants and AM fungi is of obvious importance to ecosystem processes, the factors influencing the ecological and evolutionary dynamics within this interaction are poorly understood. The mutual interdependence of plant and AM fungal relative growth rates could generate complex dynamics in which the composition of the AM fungal community changes due to association with host and this change in fungal composition then differentially feeds back on plant growth. I first review evidence for feedback dynamics and then present an approach to evaluating such complex dynamics. I specifically present evidence of host-specific differences in the population growth rates of AM fungi. Pure cultures of AM fungi were mixed to produce the initial fungal community. This community was then distributed into replicate pots and grown with one of four co-occurring plant species. Distinct compositions of AM fungal spores were produced on different host species. The AM fungal communities were then inoculated back onto their own host species and grown for a second growing season. The differentiation observed in the first generation was enhanced during this second generation, verifying that the measure of spore composition reflects host-specific differences in AM fungal population growth rates. In further work on this system, I have found evidence of negative feedback through two pairs of plant species. The dynamic within the AM fungal community can thereby contribute to the coexistence of plant species.