Compatibility of Jatropha (Jatropha curcas L.) grafting to increase production and drought stress tolerance

Abstract

This study investigates the compatibility of Jatropha curcas grafting and its impact on morphological, biochemical, and production traits under drought conditions. A split-plot design with three replications was applied, using three high-yielding scion accessions (IP-3A, PT-7, HS-49) and seven rootstock accessions (IP-3M, A-013, A-045, C-019, C-116, D-072, D-117). Evaluated parameters included morphological traits, yield components, oil content, leaf proline concentration, and graft union histology. Data were analyzed using ANOVA followed by Duncan’s Multiple Range Test (5%).  Grafting significantly enhanced growth and yield components compared to those of the non-grafted plants. PT-7 was identified as the most compatible and productive scion, while IP-3M was the most effective rootstock for promoting vegetative growth. Differences in leaf proline accumulation among the various graft combinations reflected variations in drought adaptation. Compatible graft combinations resulted in a narrower necrotic layer, stronger callus formation, and more rapid re-establishment of vascular connections. The PT-7/IP-3M combination demonstrates superior graft compatibility, growth performance, productivity, and drought adaptation. The identified graft combinations offer an effective strategy to enhance the productivity of drought-tolerant Jatropha curcas when cultivated on marginal and semi-arid lands, while simultaneously supporting a sustainable supply of biofuel feedstock amid global climate change.