Researchers Identify Wild Papaya Genes to Boost Plant Drought Resilience

A team of researchers from Mexico have identified key stress-response genes from a drought-tolerant wild papaya (Carica papaya) genotype that significantly enhance water-deficit resilience when expressed in model plants. By isolating the transcription factor genes CpMYB94 and CpSHN1 from wild relative populations, the team showed that reintroducing native wild traits can help cultivated crops survive long periods of drought without losing vital metabolic function.

To evaluate the protective role of the genes, the researchers expressed the wild papaya genes in transgenic Arabidopsis thaliana plants, and subsequently subjected them to 14 days of water-deficit stress. While the wild-type control plants failed to recover from the severe water shortage, the engineered lines expressing either CpMYB94 or CpSHN1 maintained higher photosynthetic activity and successfully recovered. Molecular tracking confirmed that CpMYB94 expression strongly correlates with increased abscisic acid accumulation, a core plant hormone that triggers protective physiological responses during drought.

Comparative transcriptomic surveys revealed that these protective gene variants are heavily expressed in wild papaya collected from its native center of origin, but have been substantially diminished in commercial papaya cultivars over generations of domestication. Unlocking these native survival mechanisms provides plant breeders with valuable genetic targets to restore climate resilience in commercial fruit crops and broader agricultural species facing intensifying water stress.