Effect of Seed Priming on Germination and Early Seedling Vigour of Onion (Allium cepa) in Sokoto State

Onion (Allium cepa) is a critical vegetable and spice crop in North West Nigeria, with Sokoto State accounting for a significant share of national production. Poor seed germination and weak seedling establishment are recurring challenges that limit productivity among smallholder onion farmers. Seed priming, a pre-sowing treatment that initiates metabolic processes before actual germination, has been reported to improve germination speed and seedling vigour in various horticultural crops. This study evaluates the effect of four seed priming treatments, including hydropriming (water), osmopriming (polyethylene glycol), biopriming (Trichoderma harzianum), and unprimed control, on the germination and early seedling vigour of onion in Sokoto, Sokoto State. The experiment was conducted in a nursery setting using a completely randomized design with four replications. Parameters assessed include germination percentage, germination speed, seedling height, root length, and vigour index at 14 days after sowing. Results indicate that osmopriming significantly improved germination percentage and seedling vigour index over all other treatments, including the control. Biopriming also showed a notable improvement in root development. The study recommends osmopriming as an economical pre-sowing treatment for improving onion seedling establishment in Sokoto State. Keywords: seed priming, onion, Allium cepa, germination, Sokoto State