Sequencing the genome of a wild banana ancestor offers a chance to improve disease resistance

Chinese scientists have decoded the high-quality genome of the wild banana Musa exotica and reconstructed the ancient karyotype of the ancestors of modern bananas. The study has allowed researchers to trace the evolution of the plant’s chromosome set and could help breeders use genetic resources from wild species to improve disease resistance in modern varieties.

Bananas are an important food crop in tropical regions, providing food for more than 400 million people. At the same time, many commercial varieties are propagated vegetatively, resulting in low genetic diversity. This makes them particularly vulnerable to the spread of dangerous fungal diseases that can cause significant crop losses.

A comparison of genetic data showed that the number of chromosomes in banana ancestors gradually declined from 17 to 9–11 during evolution. Researchers believe this process resulted from chromosome fusions, reciprocal translocations and other DNA rearrangements.

The scientists also found that chromosome breakpoints are associated with genes responsible for the synthesis of anthocyanins — pigments that give the bracts of banana inflorescences their bright colors. This indicates a link between chromosome evolution and the development of certain plant traits.

The researchers say that reconstructing the ancestral karyotype provides a basis for comparing the genomes of different banana species and identifying useful genes in their wild relatives. In the future, these findings could be used in breeding programs to develop banana varieties with greater resistance to disease, which is particularly important for a crop on which hundreds of millions of people depend.