Cold plasma pretreatment improves the germination of wild asparagus (Asparagus acutifolius L.) seeds

The cultivation of wild asparagus does not require many input because it adapts very easily to adverse pedoclimatic conditions. The main limit to its cultivation is the long time necessary for germination and the low germinability of seeds. In this study, the effect of cold plasma pretreatment on wild asparagus seed germination was evaluated. Seed plasma pretreatments (mixtures of O-2/N-2 applied for different times) were compared with conventional ones, namely: soaking (water), priming (polyethylene glycol), and hormonal (gibberellic acid). The effects of seed stratification and temperature on germination were also investigated. The stratification reduced the time required for germination of about 180 d. Plasma treatment, gas feed with 20-80% O-2/N-2 for 1 min, resulted more effective in increasing the germination percentage (by 15%) and reduced of 5 d the time to reach half of maximum germination percentage (T-50). This performance is related to both the increase in water uptake and the fungal disinfectant properties of plasma treatment. This study confirms that the application of cheap and eco-friendly cold plasma technology could provide improvements in the cultivation of wild asparagus.