Papaya grafting: Advance, mechanisms and future prospects

Papaya (Carica papaya L.) is a nutritionally rich and economically significant tropical fruit crop. Despite its importance, papaya cultivation faces challenges such as dioecy, inconsistent seed propagation and environmental influence on sex expression. Grafting has emerged as a viable vegetative propagation technique to overcome these constraints, ensuring uniformity, improved plant vigor and extended economic lifespan. Among various grafting methods, cleft grafting has demonstrated high success rates, producing hermaphrodite plants with desirable traits such as reduced fruiting height and increased productivity. The process involves intricate physiological and molecular mechanisms. These include callus formation, vascular regeneration and hormonal interactions that facilitate graft union success. Cytokinins and gibberellins play a crucial role in lateral shoot development, aiding scion production by mitigating apical dominance. Additionally, molecular studies reveal the movement of RNAs and proteins across graft unions, influencing growth regulation. Despite its advantages, papaya grafting faces challenges like bacterial rot, which can be managed through silicon application and optimized grafting conditions. This review highlights advancements in grafting techniques, emphasizing their role in enhancing propagation efficiency and improving papaya cultivation. Standardizing these techniques could provide sustainable solutions for commercial papaya production, ensuring consistent fruit quality and yield. Future research should focus on optimizing grafting methodologies, exploring resistant rootstocks and understanding genetic interactions and promoting field-level adoption to enhance commercial cultivation.