Gas-Plasma-Activated Water Impact on Photo-Dependent Dormancy Mechanisms in Nicotiana tabacum Seeds

Abstract

Seeds sense temperature, nutrient levels and light conditions to inform decision making on the timing of germination. Limited light availability for photoblastic species results in irregular germination timing and losses of population germination percentage. Seed industries are therefore looking for interventions to mitigate this risk. A growing area of research is water treated with gas plasma (GPAW), in which the formed solution is a complex consisting of reactive oxygen and nitrogen species. Gas plasma technology is widely used for sterilisation and is an emerging technology in the food processing industry. The use of the GPAW on seeds has previously led to an increase in germination performance, often attributed to bolstered antioxidant defence mechanisms. However, there is a limited understanding of how the solution may influence the mechanisms that govern seed dormancy and whether photoreceptor-driven germination mechanisms are affected. In our work, we studied how GPAW can influence the mechanisms that govern photo-dependent dormancy, isolating the effects at low fluence response (LFR) and very low fluence response (VLFR). The two defined light intensity thresholds affect germination through different phytochrome photoreceptors, PHYB and PHYA, respectively; we found that GPAW showed a significant increase in population germination percentage under VLFR and further described how each treatment affects key physiological regulators.

Advancements in Plasma Agriculture: A Review of Recent Studies

“…PAW treatment positively influenced the photo-dependent dormancy mechanisms in Nicotiana tabacum seeds [120]. It enhanced testa and endosperm rupture percentages, increased the activity of the gibberellin-3-oxidase gene, and upregulated the expansin-A4 gene, all of which contributed to improved seed germination and growth.…”

Plasma-Driven Sciences: Exploring Complex Interactions at Plasma Boundaries

“…Several studies have reported that direct plasma irradiation of plant seeds promotes germination and growth [72][73][74]. In the physiological process of seed germination [75], regulation of the balance of phytohormones, such as abscisic acid (ABA) and gibberellin (GA), stops dormancy, seed metabolism synthesizes enzymes, and seed germination occurs during seedling processes with regard to the softening of the cell wall and expansion of the shoot and root [76][77][78][79]. The mechanical properties of seeds change during physiological germination.…”

Seed priming with gas plasma-activated water in Ethiopia’s “orphan” crop tef (Eragrostis tef)

“…This results in the ionisation of the gas and the synthesis of a myriad of ions, reactive species, and free electrons (Wright et al 2018 ; Zhou et al 2020 ). GPAW has been shown to affect seed germination (Bafoil et al 2018 ) and to break seed dormancy (Grainge et al 2022a , b ).…”