Here’s the story behind our research. Calotropis procera also known as Akra is a tough, fast-growing plant that thrives in some of the harshest conditions on Earth, from dry inland plains to hot desert ecosystems. It’s already known for its strong natural fiber and medicinal properties, yet it has remained on the sidelines when it comes to modern crop development. Despite its ecological resilience and rising value, C. procera is still considered an underutilized species. One major reason? The lack of a high-quality genome and limited understanding of its agronomic traits.

That’s exactly what we set out to change. We assembled the first chromosome-scale reference genome of C. procera, using a combination of Nanopore long reads, Illumina short reads, and Hi-C sequencing. This gave us a highly contiguous, accurate genome assembly—finally offering the genomic foundation needed to explore traits, gene functions, and structural variation at a much deeper level.

From there, we dug deeper. We compared C. procera with other members of the Apocynaceae family, including Asclepias syriaca, Calotropis gigantea, and Catharanthus roseus. What we found was fascinating: there were clear expansions in gene families related to stress responses—such as those linked to drought, salinity, and heat tolerance. These are exactly the kinds of adaptations that help plants survive and thrive in arid environments.

We also uncovered strong synteny and structural rearrangements, especially in comparison with A. syriaca, suggesting a distinct evolutionary path shaped by environmental pressure. Interestingly, when we looked at other desert-adapted species like Pugionium, Stipagrostis, and members of Portulacineae, we saw similar genomic patterns highlighting convergent evolution in response to extreme climates.

Ultimately, this study does more than just assemble a genome. It delivers a powerful toolkit for:

• Identifying and tracking genes linked to fiber quality and stress adaptation
• Supporting marker-assisted breeding for future domestication efforts
• Understanding evolutionary resilience in desert ecosystems
• And offering a climate-smart alternative for sustainable agriculture

In an era of increasing climate uncertainty, wild and resilient species like C. procera could be key to building the next generation of crops. This genome is not just a scientific milestone, it’s a stepping stone toward unlocking the full potential of desert plants for a hotter, drier future.

The study described in the article "Gadri, H.S., Roy, S., Devi, S. et al. Chromosome scale assembly unveils genomic structure and gene families of Calotropis procera. Mol Genet Genomics 300, 64 (2025). https://doi.org/10.1007/s00438-025-02270-6 "