My current postdoctoral research at the University of Arizona in the Dlugosch lab asks: how do changes at the genetic level affect the phenotypic traits of introduced species in ways that may facilitate rapid range expansion? In other words, how does adaptation contribute to invasion? To answer this question, I am taking a population genomic approach to interrogate which loci in the genome are associated with so-called "invasion traits" which have been identified in invasive Yellow Starthistle (Centaurea solstitialis) populations. Specifically, I am using a combination of QTL mapping, genome-wide association, and genome-environment association-based methods to identify genetic changes associated with increased growth and reproductive output observed in Californian Starthistle populations - traits that contribute to the spread of this problematic agricultural pest. For a more detailed explanation of where I'm at with this work check out the preprint of this work or watch my recorded talk for the Plant Genomes Online conference below:
Reatini B, Cang FA, Jiang Q, McKibben MTW, Barker MS, Rieseberg LH, Dlugosch KM (in review) Chromosome-scale reference genome and RAD-based genetic map of yellow starthistle (Centaurea solstitialis) reveal putative structural variation and QTLs associated with invader traits. BioRxiv: https://doi.org/10.1101/2022.09.28.509992
My dissertation research at the University of North Carolina at Chapel Hill included theoretical and empirical approaches to interrogate the influence of hybridization on range dynamics. My theoretical work focused on three aspects of evolutionary biology: genetic architecture, hybridization, and adaptation. Genetic architecture refers to the number of genetic loci controlling a trait, the interactions between those loci, and their position within the genome. Hybridization is the interbreeding of distinct species or evolutionary lineages. Adaptation is the mechanism by which species become better suited to their environment over many generations. I am interested in the interplay between these three subjects within the greater context of biological invasions. During my PhD, I developed models to explore how the genetic architecture of adaptive traits influences the contribution of hybridization to colonization. The goal of this research was to increase our understanding of the factors which determine when and how hybridization facilitates biological invasions. For a more detailed explanation of this work check out the published version in Evolution:
Reatini B, Vision TJ (2020) Genetic architecture influences when and how hybridization contributes to colonization. Evolution: https://doi.org/10.1111/evo.13972
My empirical work during my dissertation focused on investigating the potential consequences of hybridization between native and invasive plant species in the Galápagos archipelago. Why the Galápagos? The Galápagos consists of many isolated islands which are themselves isolated from continental South America. Galápagos therefore offers an ideal natural laboratory to study evolutionary processes within varying ecological contexts and with naturally occurring experimental replicates. In addition, roughly a third of all native plant genera in the Galápagos also contain at least one introduced species. The potential for hybridization between such species is therefore considerable. I have started to investigate hybridization in five such genera: Psidium (guava), Lantana (wild sage), Passiflora (passionfruit), Gossypium (cotton), and Cenchrus (sandspur).
My most recent work focused on investigating the negative consequences of mating between endemic guayabillo (Psidium galapageium) and invasive guava (P. guajava) and its potential contribution to the ongoing range decay of guayabillo on the co-inhabited islands. The goal of this research is to improve our understanding of how maladaptive hybridization can lead to demographic decline, and use that knowledge to aid in the conservation of this protected Galápagos tree species. For a more detailed explanation of this work check out the preprint of this work or watch my recorded talk for Botany 2020 Virtual below:
Reatini B, Torres MdL, Vision TJ (in review) Local exclusion and regional decline of an endemic Galápagos tree species (Psidium galapageium) by an invasive relative (P. guajava). BioRxiv: https://doi.org/10.1101/2022.10.11.511772