Considering the prevention of crop production, aimed at
adaptation to climate changes, searching for or developing
genotypes resistant to water deficit is a challenge for
modern agriculture and a strategic goal of plant breeding.
The objective of the study was to determine the effect of
drought stress on the vigor of naked and husked oat (
Avena sativa
L.) cultivars. The studies concerned eight naked
oat cultivars and two husked oat cultivars characterized
by high germination capacity (above 95%). Seeds of
naked oat cultivars showed susceptibility to varied
thermal conditions during drought simulated by the use of
polyethylene glycol (PEG) at a concentration of -1.5 MPa.
An increase in temperature from 10 to 20 °C resulted
in an average 37% increase in the number of normally
germinating seeds, and in a more than 40% increase in
germination rate, as well as in a 25% decrease in average
germination time. A distinct increase in osmotic potential
from -1 to -2 MPa during drought stress induction resulted
in 15% decrease in vigor of husked cultivars measured
by the percentage of normally developed seedlings. The
vigor of oat cultivars, evaluated on the basis of electrical
conductivity of exudates, was modified by genotypic
variability. In naked cultivars, on average, 60% lower
values were noted. The coefficients of correlation between
electrical conductivity of exudates and germination
capacity (r = -0.784**) or frequency of normally
developed seedlings (r = -0.919**) confirm the highly
significant interrelationship between the methods used for
the evaluation of oat seeds under drought conditions.
