Filatova et al. used RF discharges for wheat seeds treatment at high
ower (50 and 100 W) and pressure of 66 Pa (Filatova et al., 2013). A
ght increase in the germination rate ofwheatwas obtained as a result
plasma exposure for a short treatment time (up to 7 min), while
nger plasma exposure results in damage of the seeds and consequent-
a drastic reduction in the germination percentage. The authors also
port an increase of the sprout length, however this is not necessarily
result of plasma treatment, since vacuum treatment without plasma
so resulted in longer seedlings. A negative effect of long plasma expo-
re was also reported by Sera et al. (2010), who found that wheat
routs of seeds treated for 3 min were significantly heavier than
ose treated for 10, 20 and 40 min. A similar behaviour was noticed
r the root-to-shoot ratio (Sera et al., 2010). In our experiments this
end was not observed. The R/S ratio was higher for the treated seeds
an for the control seeds. This is probably due to the milder plasma
eatment in the present experiments: the average power in the