Agroecología

martes, 24 de diciembre de 2024

Microbiome selection and evolution within wild and domesticated plants

Barnes et al., 2024

Microbes are ubiquitously found across plant surfaces and even within their cells, forming the plant microbiome. Many of these microbes contribute to the functioning of the host and consequently affect its fitness. Therefore, in many contexts, including microbiome effects enables a better understanding of the phenotype of the plant rather than considering the genome alone. Changes in the microbiome composition are also associated with changes in the functioning of the host, and there has been considerable focus on how environmental vari- ables regulate plant microbiomes. More recently, studies suggest that the host genome also preconditions the microbiome to the environment of the plant, and the microbiome is therefore subject to evolutionary forces. Here, we outline how plant microbiomes are governed by both environmental variables and evo- lutionary processes and how they can regulate plant health together.

A model for the ecological and evolutionary processes governing the plant microbiome. The plant selects from the locally available microbes as proposed in the two-step model by Bulgarelli et al. [37] and expanded upon by Favela et al. [38]. Here we emphasise that variations in plant microbiomes can be derived from ecological and evolutionary processes. Environmental microbiomes change rapidly in response to stresses, such as abiotic stresses. Consequently, the plant microbiome is selected for by various mechanisms, being activated/deactivated to mitigate for these fluctuations (ecological model). Meanwhile, consistent differences between environments can lead to the mechanisms being encoded in the plant genome, thereby being constitutively expressed as part of adaptation (evolutionary model). This leads to genotypic variation in plant microbiomes being observed even within standard growing conditions.

https://www.sciencedirect.com/science/article/pii/S0966842X24003147