Comparative genomics and transcriptomics analysis reveals evolution patterns of selection in the Salix phylogeny

Area of Science:

• Plant evolutionary biology
• Comparative genomics
• Phylogenetics

Background:

• Willows (Salix) are widespread and adaptable plants.
• Increasing genomic and transcriptomic data enable evolutionary studies.

Purpose of the Study:

• To investigate evolutionary patterns in Salix phylogeny.
• To understand divergence and adaptation based on origin and distribution.

Main Methods:

• Comparative transcriptomic analysis of 10 Salicaceae species.
• Identification of orthologous sequences and construction of a phylogenetic tree.
• Estimation of divergence times and identification of positively selected genes.

Main Results:

• Phylogenetic tree constructed, revealing divergence times.
• Identified fast-evolving sequences and stress-resistance genes (cold, drought, light, heat).
• Positive selection detected in cold-, light-, and universal-stress genes.

Conclusions:

• Salix subgenera diverged around 17.6-16.0 Mya during the Middle Miocene Climate Transition.
• Subgenus Vetrix split into migratory and resident groups around 14 Mya in response to climate change.
• Adaptive evolution and speciation in Salix are linked to stress-resistance genes.