Study of Direct and Indirect Plasma Application on Onion Seeding Bulbs: Small Multi‐Field Experiment

Cold atmospheric‐pressure plasma is a promising tool for sustainable agriculture due to its generation of reactive oxygen and nitrogen species (RONS). This study evaluated direct corona discharge and plasma‐activated water (PAW) treatments on onion bulbs at seven field sites. Bulbs were treated by corona discharge (2 × 10 s or 2 × 40 s) or soaked for 24 h in PAW produced by dielectric barrier discharge. Volatile compounds were analyzed by GC–MS and PTR–TOF–MS. The 2 × 10 s corona treatment increased average bulb weight by 7.5%, with positive responses at six of seven sites, and enhanced propanal concentration at five sites (mean +26.3% vs. control). Water‐based treatments showed only minor, nonsignificant effects.