NYCSEA

Abstract: Maize is the most important agricultural species in sub-Saharan Africa, supplying approximately 50% of the calories and proteins consumed. Due to increasing drought conditions from climate change, maize crop yields are projected to decline by 24% in the next decade. New strategies to aid farmers in coping with drought circumstances are urgently needed. Seed priming or presoaking (soaking seeds in a solution before planting) has been proposed to improve drought tolerance. Melatonin, a plant growth regulator, improves drought tolerance through multiple mechanisms. This project investigated whether priming maize seeds with melatonin could improve germination and drought tolerance. We hypothesize that priming maize seeds in a melatonin solution would improve plant drought tolerance. Three groups of 60 maize seeds were created: Group 1 control (no priming), Group 2 priming with water, and Group 3 priming with a melatonin solution (100 µM). Seeds were primed for 6 hours and then germinated. Seeds were planted and exposed to drought conditions for 14 days. Cumulative percent germination was higher in the water and melatonin primed groups and lowest in the control group (p-value < 0.05). Cotyledon (first leaf) emergence was earliest for melatonin primed group and latest for the control group (p-value < 0.05). The melatonin primed group was superior to the control and water primed groups in plant height, weight, and viability after drought exposure (p-value <0.05). This study demonstrated that seed priming with melatonin improved plant height, weight, and viability under drought conditions, when compared to priming with water or no priming. Priming seeds with melatonin may offer a simple method of improving drought tolerance in maize plants.

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