Seed Priming Strategies for Improving Maize Germination under Drought

Climate change presents significant challenges for the agri-food sector, particularly drought, which is characterized by extended periods of water scarcity and severely impacts crop productivity and food security. To counter these effects, the adoption of sustainable agricultural practices is essential. While drought stress has been extensively studied during the vegetative and reproductive stages, its impact on germination remains poorly studied. Therefore, this work proposes to investigate the effects of drought at the germination stage in a collection of Italian maize varieties. The objectives of the work include (1) identification of maize varieties susceptible or tolerant to drought, and (2) the development of sustainable protocols to improve seed germination under drought. The treatments include using plant-derived biostimulants (PBs), natural substances that can enhance plant growth and stress resilience. PBs are employed for seed priming, a method developed to improve germination performance. PBs from red chicory and cauliflower waste products are obtained and applied as seed priming agents to investigate drought resilience at the germination stage in maize. Germination efficiency is monitored for 14 days under soil drought stress under controlled conditions. Multiple germination parameters (percentage, speed, synchrony, uniformity, and seedling growth) are monitored to evaluate the effects of priming treatments and drought levels. Preliminary results evidence that PBs improve seed germinability under drought stress. This work is part of the project NODES, which has received funding from the MUR – M4C2 1.5 of PNRR funded by the European Union - NextGenerationEU (Grant agreement no. ECS00000036).