Factors triggering germination in plasma-activated cotton seeds: water imbibition vs. reactive species’ formation

Abstract

E Arroyo et alanalysis by FT-IR of the adsorption of deuterated water (D 2 O) molecules is proposed as a useful procedure to directly monitor water uptake/release processes from seed surfaces.

Comparative analysis of the germination of barley seeds subjected to drying, hydrogen peroxide, or oxidative air plasma treatments

“…This can be directly inferenced when treating the seeds with H 2 O 2 , [ 41–45,48 ] but it is not so evident for the plasma treatments where the role of RONS in activating the germination is still a likely hypothesis. [ 5,49 ] In the present study with barley seeds, hints by XPS suggest the formation of similar species upon plasma treatment. In recent work, the formation of very reactive radical species in barley seeds subjected to plasma treatments has been proved by electron paramagnetic resonance.…”

“…Similar behavior has been found by us for quinoa and cotton seeds exposed to plasma treatments. [ 5,49 ] These evidence revealed that although the surface topographic changes induced by plasma are not quite significant, a certain mobilization and out‐diffusion of some elements takes place as a result of this treatment. We tentatively propose that the observed diffusion of elements likely responds to changes in chemical potential induced at the surface by the plasma treatments.…”

“…The set of experiments in Figure 9 suggests that plasma acts similarly to the H 2 O 2 treatment and, in this way, supports the fact that the main reason for the positive effect of plasma in accelerating the germination of seeds is the formation of RONS species on the surface of seeds and their diffusion and reaction with ABA, as previously suggested in other works using plasmas. [ 5,49 ] However, to our knowledge, no other works in literature have carried out a similar empirical study comparing the effect of H 2 O 2 and plasma in relation to the inactivation of ABA, as evidenced by the data in Figure 9.…”

“…Further details about the reactor and operating conditions can be found in previous publications. [5,49]…”

“…An important factor affecting seed germination and plant growth refer to their contamination degree, [1,[18][19][20][21]51] a feature that can be positively decreased by the plasma treatments as a prevention method. [5,18,19,49] Figure 2a shows the contamination degree, defined and determined as described in the experimental section, for the plasmatreated seeds, the control set, and the dry seeds. An example of the appearance of contamination in seeds is reported in Figure 2b.…”