Low-energy electron beam has severe impact on seedling development compared to cold atmospheric pressure plasma

Abstract

Sprouts are germinated seeds that are often consumed due to their high nutritional content and health benefits. However, the conditions for germination strongly support the proliferation of present bacteria, including foodborne pathogens. Since sprouts are consumed raw or minimally processed, they are frequently linked to cases of food poisoning. Therefore, a seed decontamination method that provides efficient inactivation of microbial pathogens, while maintaining the germination capacity and quality of the seeds is in high demand. This study aimed to investigate and compare seed decontamination by cold atmospheric-pressure plasma and low-energy electron beam with respect to their impact on seed and seedling quality. The results show that both technologies provide great potential for inactivation of microorganisms on seeds, while cold plasma yielded a higher efficiency with 5 log units compared to a maximum of 3 log units after electron beam treatment. Both techniques accelerated seed germination, defined by the percentage of hypocotyl and leaf emergence at 3 days, with short plasma treatment (< 120 s) and all applied doses of electron beam treatment (8–60 kGy). However, even the lowest dose of electron beam treatment at 8 kGy in this study caused root abnormalities in seedlings, suggesting a detrimental effect on the seed tissue. Seeds treated with cold plasma had an eroded seed coat and increased seed wettability compared to electron beam treated seeds. However, these effects cannot explain the increase in the germination capacity of seeds as this was observed for both techniques. Future studies should focus on the investigation of the mechanisms causing accelerated seed germination and root abnormalities by characterizing the molecular and physiological impact of cold plasma and electron beam on seed tissue.

Changes in Content of Bioactive Compounds and Antioxidant Activity Induced in Needles of Different Half-Sib Families of Norway Spruce (Picea abies (L.) H. Karst) by Seed Treatment with Cold Plasma

“…These can be key aspects for developing and using plasma technologies in the food industry, medicine, ecology, and agriculture [ 19 ]. Research on cold plasma (CP) applications for agriculture is relatively new but an extremely rapidly developing area, as reflected by the large number of recent reviews [ 20 , 21 , 22 , 23 , 24 , 25 ]. It has been demonstrated that seed treatments with CP may have significant positive effects on germination, plant biochemical processes, photosynthesis [ 26 , 27 ], and biomass growth [ 27 , 28 ] and could increase harvest yields of numerous plant species.…”

RNA Sequencing of Arabidopsis thaliana Seedlings after Non-Thermal Plasma-Seed Treatment Reveals Upregulation in Plant Stress and Defense Pathways

“…A limitedtreatment time was chosen to avoid additional stresses such as heat stress, which induces a plethora of cellular effects [35][36][37][38]. Early germination was the macroscopic parameter used as an indicator of changes in the molecular biology, as shown in Figure 1, which is an effect observed in other studies [39].…”

Ionizing Radiation: Effective Physical Agents for Economic Crop Seed Priming and the Underlying Physiological Mechanisms

“…Pekinensis ) seeds, 0–3 kGy electron treatments activated the defense mechanism to the pathogen ( Fusarium graminearum ) and reduced the infection rate, while the seed quality had not been reduced below the commercial threshold of 91.83% seed germination [ 80 ]. The stress resistance effects induced by low levels of electron beam radiation have also been reported by Waskow, and they showed that 8–60 kGy irradiation inactivated the microbial pathogens and stimulated various aspects of the plant’s development such as accelerating the germination of Lens culinaris seeds [ 47 ]. However, it must be mentioned that the specific impact on seeds also depends on the type of pathogen, the radiation source, and the seed used.…”