Atmospheric-pressure cold plasma assisted enhancement of germination and nutritional trait of peanut seeds

Introduction Improving seed germination and early seedling growth using environmentally friendly, chemical-free technologies is essential for enhancing crop productivity and agricultural sustainability. This study investigated the effects of low-power dielectric barrier discharge (DBD)-based ACP treatment on the physicochemical characteristics, germination, antioxidant activity, and early seedling growth of peanut seeds. Methods Peanut seeds were treated with DBD-based ACP for 10, 20, 30, 40, and 50 s. Optical emission spectroscopy (OES) was used to identify reactive oxygen and nitrogen species generated during plasma treatment. The effects of different plasma exposure times on seed germination, seedling growth, vigor, wettability, antioxidant activity, elemental composition, functional groups, and surface morphology were evaluated. Antioxidant activity was determined using DPPH and ABTS assays, while Fourier-transform infrared spectroscopy (FTIR), inductively coupled plasma mass spectrometry (ICP-MS), and field-emission scanning electron microscopy (FESEM) were used to characterize the treated seeds and sprouts. Results Among the tested exposure times, 40 s was identified as the optimal plasma treatment condition. Compared with untreated seeds, the optimized treatment significantly increased the germination rate, seedling growth, germination potential, germination index, vigor index, and seed wettability by 9.67%, 45.13%, 11.09%, 13.85%, 61.77%, and 28.98%, respectively. DPPH antioxidant activity increased from 2.495 to 2.850 mg Trolox/g DW, while ABTS activity increased from 6.195 to 6.430 mg Trolox/g DW. ICP-MS analysis showed increases in Na, B, Ca, Mg, Al, and Fe contents of 77.80%, 54.37%, 72.92%, 35.41%, 75.77%, and 65.81%, respectively, in treated peanut sprouts. Discussion The results demonstrate that brief exposure to low-power DBD-based ACP, particularly for 40 s, can effectively enhance peanut seed germination, vigor, seed wettability, antioxidant activity, elemental composition, and early seedling growth. These improvements are associated with plasma-induced changes in reactive species, seed surface morphology, and physicochemical characteristics. The findings highlight the potential of ACP as an environmentally friendly, chemical-free, and scalable technology for seed treatment and agricultural applications.