Among the most remarkable specializations of plant parasites are sedentary endoparasites that induce nurse cells in host plant roots that serve as metabolic sinks and nematode feeding sites, sustaining the sedentary female nematode during its lifetime in the host tissue.
Darwin (1862) was the first to postulate that the development of greatly extended mouthparts takes place in a coevolutionary race that leads to a mutualistic specialization of nectar plants and their pollinating insects.
The specialization of the plant body, which has evolved as an adaptation to a principally terrestrial habitat, includes extensive root systems that anchor the plant and absorb water and minerals from the soil; a stem that supports the growing plant body; and leaves, which are the principal sites of photosynthesis for most angiospermous plants.
Alternatively, it might be the result of greater than expected specialization of the plant and animals in this system leading to relatively abundant but specialized species.
Across networks, the average specialization of animal and plants was correlated, but is constrained by the ratio of plant to animal species involved.
However, recent network studies suggest that this is not the case - plants and animals in pollination and seed dispersal networks exhibit a similar range of specialization with plants on average more generalized than insects [ 29].
After the divergence of mosses from vascular plants, a second expansion took place that likely correlated with the specialization of vascular and flowering plants [ 1].
In addition, a 4 bp insertion in the Obp57e gene in D. sechellia results in loss of avoidance of hexanoic acid and octanoic acid produced by its host plant, Morinda citrifolia, and supports host plant specialization of this species (Matsuo et al. 2007).
In this article, I provide an overview of mechanisms enabling adaptation and specialization of phytobiome communities to host plants as well as the potential for plants themselves to recruit and cultivate beneficial interactions.
This may be due to duplication and specialization of the members along plant speciation after P. patens.
