干旱区生态环境知识资源中心

In interspecific mutualisms, the interacting species generally disperse independently, by which the colonization must be restricted by the reassociation between them. We theoretically analyzed colonization process of mycorrhizal plant in a novel habitat, focusing on the probability of colony establishment under environmental fluctuation. The process is a joint process of two sub-processes before and after the association between the plant and the mycorrhizal fungi. Properties of whole system are influenced by five parameters, means and variances of colony growth rates of two sub-systems, and a reassociation rate. Our analysis revealed that (1) the mean colony growth rates of the host alone and the symbiotic association affect establishment probability in different ways, and (2) a trade-off between the mean colony growth rates of the host alone and the symbiotic association could result in the evolution of either a symbiotic or parasitic relationship, based on a host decision.