January 16, 2026 | BMC Plant Biology | Rozman
Universiti Putra Malaysia, Malaysia, investigated a combined treatment strategy for enhancing drought tolerance in papaya (Carica papaya L.), a major tropical fruit crop affected by water stress. Papaya’s shallow root system, high transpiration rate, and high water content make it particularly vulnerable to drought, which threatens productivity under changing climate conditions.
The study evaluated the effects of calcium carbide (CaC₂), gibberellic acid (GA₃), and their combined application under different soil moisture levels (100%, 75%, and 50% field capacity). Over a 12-week period, physiological and growth responses of papaya seedlings were measured. The combined CaC₂ and GA₃ treatment showed the strongest effect, maintaining higher photosynthetic rates and preserving up to 78% of optimal biomass under severe drought conditions compared to untreated controls. Treated plants also exhibited reduced stress indicators, such as lower proline accumulation, while maintaining growth, suggesting improved stress adaptation mechanisms.
In addition, the combined treatment enhanced chlorophyll content and photosynthesis even under well-watered conditions, indicating a broader growth-promoting effect. The results suggest that co-application of CaC₂ and GA₃ can improve drought resilience by maintaining metabolic activity and reducing stress-related damage. This approach provides a practical strategy for enhancing climate resilience in papaya and potentially other tropical fruit crops.





