ISSN 10214437, Russian Journal of Plant Physiology, 2012, Vol. 59, No. 1, pp. 71–78. © Pleiades Publishing, Ltd., 2012.
Original Russian Text © N.L. Radyukina, V.I. M. Toaima, N.R. Zaripova, 2012, published in Fiziologiya Rastenii, 2012, Vol. 59, No. 1, pp. 80–88.
Under unfavorable environmental conditions, as a
rule, plants are subjected to simultenous action of sev
eral stressors, for example, drought and high tempera
ture, salinity and heavy metals, UVB radiation and
salinity . In this case, two stressors could exert addi
tive, synergistic, or antogonistic effects. In recent
time, the hypothesis that the basics for plant adapta
tion and crossadaptation to unfavorable conditions is
an efficient functioning of the antioxidant system
because oxidative stress is a common adverse conse
quence of each stressor . However, the mechanisms
of crossadaptation remain poorly studied.
In publications devoted to the problem of plant
crossadaptation, the involvement of both low and
highmolecular compounds in this process was shown.
Thus, Cakirlar et al.  showed that successive action
of 200 mM NaCl and UVB radiation on four barley
cultivars resulted in the accumulation of proline and
carotenoids in them. Prasad et al.  studied the com
bined effect of UVB radiation and cadmium on
sp. plants and found that the two stressor combina
tion resulted in the stronger inhibition of photosystem
functioning, the increased ROS generation, and the
stronger activation of superoxide dismutase (SOD)
and peroxidase, and also an increased content of low
molecular antioxidants, ascorbate and carotenoids. In
another work , it was shown that, at combined
treatment with low abovezero temperature and UVB
plants, only temperature
treatment but not UVB radiation affected the content
of phenolic compounds. Combined treatment of
calli with UVB radiation and NO
increased the content of flavonoids in them . Pre
heateing (up to
) of melon seedlings increased
their tolerance to successive UVB irradiation .
Simultaneous action of temperature, salinity, and UV
B radiation on the microalga
in synergism in the action of these three factors .
Wheat seedling treatment with salt, high temperature,
and their combination, the changes in the content of
proline and activities of its metabilism enzymes were
The Involvement of LowMolecular Antioxidants
in CrossAdaptation of Medicine Plants to Successive Action
of UVB Radiation and Salinity
N. L. Radyukina
, V. I. M. Toaima
, and N. R. Zaripova
Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya ul. 35, Moscow, 127276 Russia;
fax: 7 (499) 9778018; email: email@example.com
People’s Friendship University, Moscow, Russia
Received February 22, 2011
Web.), common basil
L.), and black cumin
L.) plants grown in water culture until the stage of 4–5 true leaves were subjected to 10min
UVB irradiation, treated with 100 mM NaCl, or subjected to the successive action of both stressors. The
contents of proline, anthocyanins, flavonoids, soluble phenols, and carotenois were measured. Superoxide
dismutase activity was also assayed. Experimental plants could tolerate UVB irradiation due to the accumu
lation of phenolic compounds (anthocyanins, soluble phenols, and flavonoids). Anthocyanins contributed
mostly in the defnse effect; their content in black cumin and common basil increased 3–5fold after irradia
tion. Dynamics of the anthocyanin content in tested plants of all treatments indicates the activation of their
biosynthesis by UVB irradiation and suppression by salinity. Successive action of stressors resulted in syner
gism of their effects on accumulation of lowmolecular compounds in artemisia and common cumin plants.
When these plants were irradiated with UVB and then treated with NaCl, they accumulated more low
molecular compounds than after separate treatment with these stressors, especially in Artemisia. Plant pre
treatment with UVB reduced the adverse action of salinity; this was manifested in the turgor maintenance in
salttreated plants after preliminary irradiation. For basil, salinity was the stronger stressor than UVB, which
was manifested in a decrease in the content of lowmolecular compounds.
Keywords: Artemisia lercheana, Ocimum basilicum,
, superoxide dismutase, lowmolecular anti
oxidants, UVB, NaCl, stress.
: SOD—superoxide dismutase.