Host Range Evolution in Viruses

The host range refers to the number of host species used by a pathogen. It is a key factor in understanding pathogen epidemiology and pathogenicity. However, it is not an immutable trait and is influenced by ecological factors such as species distribution and interaction.

Estimating a virus host range is difficult because identifying all 'non-hosts' is practically impossible. This task is particularly challenging for plant viruses, and knowledge on host ranges may be limited, especially in wild ecosystems.

Host range evolution may result in a shift or change between hosts, or in the acquisition of new hosts or loss of existing ones. This contributes to the ability of the virus to encounter new hosts and adapt to ensure effective between-host transmission.

<p>Ecological factors such as species distribution, abundance, and interaction determine the range of potential hosts a virus comes into contact with. These factors play a central role in shaping the host range of a virus.</p> Signup and view all the answers

<p>Studies have favored viruses causing diseases in crops, leading to limited knowledge on host ranges in wild ecosystems. Interactions in wild ecosystems remain relatively unexplored compared to those in agricultural settings.</p> Signup and view all the answers

<p>Host resistance, tolerance, susceptibility, and pathogen virulence</p> Signup and view all the answers

<p>Connectivity covaries with biodiversity and affects contact rates, influencing virus expansion or host range alteration</p> Signup and view all the answers

<p>Host resistance, tolerance, susceptibility, and pathogen virulence are hypothesized to play a role in infection distribution</p> Signup and view all the answers

<p>The conceptual framework highlights the indirect effects of evolutionary and ecological factors in causing disease spread</p> Signup and view all the answers

<p>Prevalence-diversity relationships are affected by host diversity of a given habitat and habitat-related host ranges of plant viruses</p> Signup and view all the answers

<p>Co-infection affects the pleiotropic effects of resistance-breaking mutations on plant virus multiplication, depending on the type and combination of mutants.</p> Signup and view all the answers

<p>Environmental factors such as multiple or single infection may modulate across-host fitness trade-offs in the evolution of host range for plant viruses.</p> Signup and view all the answers

<p>Conflicting trade-offs between different fitness components, such as reproduction and survival, may constrain the evolution of organisms, including plant viruses.</p> Signup and view all the answers

<p>Selection for a broader host range in plant viruses involves altered particle stability and survival, indicating selection for traits not directly related to the plant-virus interaction.</p> Signup and view all the answers

<p>Virus fitness trade-offs, community connectivity, and environmental heterogeneity influence the evolution of a species' resource breadth, including plant viruses.</p> Signup and view all the answers

<p>The major intrinsic factor is genetic specificity, while extrinsic factors include ecology and epidemiology.</p> Signup and view all the answers

<p>The GFG and MA co-evolutionary models are used to analyze the interactions between host resistance genes and pathogen avirulence genes. These models have been applied to analyze plant virus host range evolution.</p> Signup and view all the answers

<p>Virus-host interaction networks can be modular or nested, with the structure depending on geographical and taxonomical scales.</p> Signup and view all the answers

<p>Specificity of infection leads to adaptive trade-offs among hosts, hindering host range expansion and favoring the evolution of specialism rather than generalism.</p> Signup and view all the answers

<p>Resistance-breaking mutations in viruses can have pleiotropic effects on virus multiplication, depending on the specific mutation and the susceptible host genotype.</p> Signup and view all the answers