Plasma treatment effects on seed germination and physiological and enzymatic characteristics of Alyssum homalocarpum L. seedlings

This experiment was conducted to investigate the plasma treatment effects on seed germination characteristics of Alyssum homalocarpum L. The initial test of plasma on seeds was by atmospheric DBD with a duration of 30 and 15 seconds and 1 to 5 minutes at voltages of 17, 18, 19 and 20 kV, and counting the daily germination of seeds was repeated for 21 days. The seeds were then treated again with atmospheric DBD plasma (30 s and 1 min) at the same voltages and monitored for 21 days. In both times, the changes were observed in the first 3 days, then the seeds were treated with DBD plasma at times of 10, 30 seconds, 1 and 3 minutes. At the end of the initial tests, the seeds were treated in DBD plasma with atmospheric pressure (30 seconds and 1 minute) at voltages of 18 and 20 kV and with DBD corona plasma for 10, 30 seconds, 1 and 3 minutes. Germination rate and percentage, plumule length, radicle length, fresh and dry weight of root and seedling, leaf area and enzyme characteristics were measured. The means comparison results showed that the highest rate (2 seeds per day) and germination percentage (70%) were obtained in the combined treatment of 18 kV and 60 sec. The results showed that the effect of time on dry weight, leaf length, root length and leaf diameter was significant at 1% level. In terms of mean comparison, catalase enzyme and polyphenol oxidase enzyme had a significant difference in the treatments of the combined effect of voltage 20 kV and time 60 seconds and the mutual effect of voltage 18 kV and time 60 seconds. Overall, according to the present findings, the atmospheric DBD plasma and corona plasma pretreatments had a role in improving growth traits and enzymes involved in the biosynthesis of secondary metabolites compared to other treatments without damaging the seeds.