Preprint: Thirteen years of genomic selection in Brazilian cassava shows sustained genetic gain with managed diversity

A preprint deposited on bioRxiv (22 July 2026) reports a longitudinal assessment of genomic selection outcomes in the Brazilian cassava (Manihot esculenta) breeding programme, covering four recurrent selection cycles — designated C0 to C3 — implemented between 2011 and 2024. The analysis draws on historical phenotypic and genomic data from 210 multi-environment trials, making it one of the most data-rich evaluations of long-term genomic selection in a clonally propagated crop.

The authors integrate measures of predictive accuracy, realised genetic gain (the actual improvement observed in evaluated lines), and genetic diversity metrics across cycles. Long-term evaluations of this kind are uncommon in clonal crops, where the interplay between accelerated selection, reduced generation intervals, and the risk of genetic erosion is particularly consequential for breeding sustainability.

Cassava is a staple crop for hundreds of millions of people across sub-Saharan Africa, Latin America, and Asia; improving its yield, disease resistance, and nutritional quality is a major target for food security research. The results are relevant to quantitative geneticists, crop breeders, and researchers developing genomic selection frameworks for other vegetatively propagated species. Educators teaching applied quantitative genetics or plant breeding methodology will find the longitudinal design instructive.

This work is a preprint and has not yet been peer-reviewed.