1021-4437/02/4904- $27.00 © 2002
Russian Journal of Plant Physiology, Vol. 49, No. 4, 2002, pp. 496–500. Translated from Fiziologiya Rastenii, Vol. 49, No. 4, 2002, pp. 553–557.
Original Russian Text Copyright © 2002 by Yusufov, Alieva.
The problem of plant integrity is for a long time
studied by plant physiologists [1, 2]. However, no gen-
eral theory of integrity was yet created , despite the
fact that physiologists repeatedly demonstrated its
important role [4–7]. Integrity can be determined as a
complex morphologically and physiologically inte-
grated system , which manifests itself in the well-
coordinated interaction of plant structures aimed at the
maintenance of stability of the whole system. Such sys-
tem was developed during ontogenetic and evolution-
ary development of plants and cannot be reduced to a
purely mechanical combination of its parts .
In this connection, it was of interest to study the pos-
sibility of estimating stress tolerance of plants by study-
ing responses of cultured plant parts and the organs of
the intact plant. To this end, we examined the threshold
level of organ susceptibility to adverse environmental
factors (the lowest concentration of solution that can
reduce their viability).
MATERIALS AND METHODS
We studied sunﬂower (
kidney bean (
L.) plants. Seeds were
germinated in washed sand. Leaves (without buds) with
and without petioles, as well as hypocotyl and stem cut-
tings, were detached from 5–30-day-old seedlings.
Stem cuttings were cut under cotyledons and used in
experiments with or without apices and leaves. Hypo-
cotyl cuttings with or without apices and cotyledons
were cut at a distance of 1–2 cm above the root system.
The cuttings were exposed to NaCl in penicillin ﬂasks
containing 8 ml of the NaCl solution (two cuttings per
ﬂask). Water or diluted liquid MS medium were used as
control solutions. All experiments were performed
under similar conditions (25
C, ambient light).
Some experiments were performed under sterile
conditions. In this case, explants of hypocotyls, leaf
blades, and cotyledons of 5–10 mm in size were cul-
tured on MS medium supplemented with NaCl (85 and
170 mM) in the presence of IBA (0.5 mg/l) and BA
Viability (the percentage of viable cuttings of their
total number as measured at different times), rooting,
and regeneration activity (callus and root formation)
were evaluated. The content of sodium ions (mg/g dry
wt) of various structures in each treatment was mea-
sured after dry matter incineration at 450–500
measurements were made with the use of an AASIN
atomic absorption spectrometer (Carl Zeiss, Germany).
Tables show mean values of three independent
experiments, each made in 20 replications, and their
standard errors; the ﬁgure shows mean values of two
experiments, made in ﬁve replications, and their stan-
RESULTS AND DISCUSSION
Under natural conditions, leaves and cotyledons dif-
fer in their life duration. These differences were seen
also in cultured cuttings, indicating an endogenous con-
trol of senescence and different regeneration capacity
[10, 11]. It should also be noted that regeneration activ-
ity, which is important for viability of cultured cuttings,
is affected by many factors. Regeneration activity is
more expressed in juvenile plants . Stem cuttings of
Viability of Plants and Isolated Organs under Salinity Conditions
A. G. Yusufov and Z. M. Alieva
Department of Plant Physiology and Darvinism, Faculty of Biology, Daghestan State University,
Makhachkala, ul. Gadzhieva 43a, 367025 Daghestan;
fax: 7 (8722) 68-2326; 68-2332; e-mail: firstname.lastname@example.org
Received July 12, 2001
—The viability and root formation of whole seedlings and isolated organs were compared in kidney
L.) and sunﬂower (
L.) plants grown in the presence of various con-
centrations of sodium chloride. The response of plant structures depended on the level of their organization.
Organ tolerance to NaCl and its ability to root formation increased with the complexity level of the system com-
prising this organ. We suppose that plant integrity represents a special functionally labile system, which deter-
mines plant resistance to adverse environmental conditions. It is noted that the response of individual structures
does not necessarily reﬂect characteristics of the intact plant tolerance.
Key words: Helianthus annuus - Phaseolus vulgaris - plant integrity - isolated organs - viability - regeneration -
salt tolerance - in vitro
: BA—benzyladenine; IBA—indolebutyric acid;
MS—Murashige and Skoog nutrient medium.