What can a curated chromosome database reveal when applied to an entire plant family?
Our new Nitrariaceae study shows how ChromoDB can transform dispersed chromosome counts, genome-size data and genomic evidence into a taxonomically resolved and reusable evolutionary synthesis. The preprint and underlying dataset are now openly available:
Simon Pallisé, J. & Bosch Daniel, M. (2026). Chromosome-number diversity and evolution in Nitrariaceae: a critical synthesis of cytological, genome-size and genomic evidence. EcoEvoRxiv.
DOI: 10.32942/X22X1X
The study provides a critical synthesis of chromosome-related evidence across Nitrariaceae, integrating historical cytological reports with more recent flow-cytometric, genome-size and genomic data. Taxonomic changes, uneven sampling and somatic chromosome-number variation were also taken into account when evaluating the available evidence.
Why Nitrariaceae?
Nitrariaceae provided a particularly useful test case for applying the full ChromoDB workflow to a complete plant family. The group is sufficiently small to allow detailed examination of individual records, while presenting many of the problems commonly encountered in chromosome-number databases: historical literature, changing taxonomic concepts, conflicting counts, inferred chromosome numbers and heterogeneous types of evidence.
The resulting synthesis therefore goes beyond compiling chromosome numbers. Each record was evaluated in its taxonomic and bibliographic context, allowing direct cytological observations to be distinguished from values inferred from genome-size or genomic evidence.
From database records to biological interpretation
One of the central aims of ChromoDB is not simply to accumulate chromosome counts, but to transform dispersed observations into taxonomically resolved, traceable and reusable evidence.
The Nitrariaceae study illustrates this approach particularly well. Taxonomic reassignment and database structure themselves can substantially affect the apparent chromosome-number spectrum attributed to a species. The analysis supports x = 12 as a robust operational framework for extant Nitraria and Peganum, while the ancestral chromosome number of the family remains unresolved.
More generally, the study highlights the need to integrate classical cytology with voucher information, meiosis, flow cytometry and chromosome-scale genomic data when reconstructing chromosome evolution.
An open and reusable dataset
The complete dataset underlying the study has also been deposited independently in Zenodo, allowing the records and bibliography used in the synthesis to be inspected and reused.
This combination of an open preprint, an openly archived dataset and the continuously curated ChromoDB database is intended to make the evidence behind the conclusions as transparent as possible.
Explore the study
Read the preprint
EcoEvoRxiv — DOI: 10.32942/X22X1X
Access the dataset
Zenodo — DOI: 10.5281/zenodo.22538050
Explore ChromoDB
ChromoDB — Plant Chromosome Database