Genome Size Diversity and Its Impact on the Evolution of Land Plants

Abstract

Genome size is a biodiversity trait that shows staggering diversity across eukaryotes, varying over 64,000-fold. Of all major taxonomic groups, land plants stand out due to their staggering genome size diversity, ranging ca. 2400-fold. As our understanding of the implications and significance of this remarkable genome size diversity in land plants grows, it is becoming increasingly evident that this trait plays not only an important role in shaping the evolution of plant genomes, but also in influencing plant community assemblages at the ecosystem level. Recent advances and improvements in novel sequencing technologies, as well as analytical tools, make it possible to gain critical insights into the genomic and epigenetic mechanisms underpinning genome size changes. In this review we provide an overview of our current understanding of genome size diversity across the different land plant groups, its implications on the biology of the genome and what future directions need to be addressed to fill key knowledge gaps.

Keywords: C-value; genome size; giant genome; polyploidy; transposable elements.

Figure 1

Phylogenetic tree illustrating the main taxonomic lineages across land plants summarized at the family level (extracted from Zanne et al. [14]). Average GS values are depicted for each family and branches leading to families without any GS data are shown in bold. (ANA-grade refers to species belonging to the three early-diverging angiosperm orders Amborellales, Nymphaeales and Austrobaileyales [12]).

Figure 2

Violin plots illustrating the frequency and range of GS across the major land plant lineages. N.B. the taxonomic groups and colour schemes reflect the same lineage diversity as depicted in Figure 1. (ANA-grade refers to species belonging to the three early-diverging angiosperm orders Amborellales, Nymphaeales and Austrobaileyales [12]).