1021-4437/03/5003- $25.00 © 2003
Russian Journal of Plant Physiology, Vol. 50, No. 3, 2003, pp. 293–296. Translated from Fiziologiya Rastenii, Vol. 50, No. 3, 2003, pp. 332–335.
Original Russian Text Copyright © 2003 by Spivak, Kisel, Yakovleva.
Plants are known to possess a complex of defense
responses, that is, an inherent immune system activated
by infection with various phytopathogens or by
mechanical wounding of plant tissues [1, 2]. At present,
it is established that plants possess a signaling system,
through which the defense mechanisms are realized.
The activation of speciﬁc receptors by signaling mole-
cules triggers a chain of biochemical reactions provid-
ing for plant resistance to various stress factors, includ-
ing phytopathogens . The products of reactions cat-
alyzed by phospholipases A
, C, and D are invoked in
this activation .
In particular, phospholipase A
plays a highly sig-
niﬁcant role in regulating plant defense systems. This
enzyme catalyzes the hydrolysis of
-2 ester moiety of
glycerophospholipids with the formation of lysophos-
pholipids and free, predominantly unsaturated, fatty
acids, that is, linoleic and linolenic. An increase in the
content of these fatty acids caused by wounding is
accompanied by the accumulation of jasmonic acid .
The latter is directly involved in the regulation of plant
responses to the changes in environmental factors and
to phytopathogens [5, 6]. A possible role of the second
product of lipolysis, lysophospholipid, in the regulation
of plant immune system remains virtually unknown.
The objective of this work was to investigate the
properties of lysophosphatidylcholine (LPC) as an
inducer of the systemic resistance of plants of the fam-
ily Solanaceae Juss., potato and tobacco, after their
infection with phytopathogens,
(Mont.) de Bary and potato virus Y (PVY).
MATERIALS AND METHODS
Plant material and phytopathogens.
L., hybrid 78563-76) plants sus-
ceptible to late blight were used in this work; this potato
line is vulnerable to phytophthora both under natural
conditions and after an artiﬁcial infection. The phyto-
pathogen culture was kindly provided by G.K. Zhurom-
sky, Potato Institute, National Academy of Sciences of
Belarus. Plants were grown from tuber eyes using 64-
cell trays ﬁlled with peat. The eyes were cut from
tubers, immersed for 30 min in 0.02 or 0.15 mM aque-
ous micellar solution of LPC and then planted into peat
(eight eyes per treatment). The control eyes were
planted out in peat without preliminary incubation in
the LPC solution. The plants were grown at a photope-
riod of 16 h, an illuminance of 4 klx, and a temperature
C for 1.5 months and then sprayed with a sus-
(Mont.) de Bary
conidia containing 3.5
conidia per ml.
The trays with plants were covered with a poly-
ethylene ﬁlm in order to maintain the humidity neces-
sary for late blight development, and the plants were
cultured at 18–20
C under scattered light. The injury
was recorded on the 5th–7th days after infection. The
resistance was assessed using a universal scale for ﬁeld
conditions calibrated to nine relative units .
Effects of LPC on plant resistance to the viral infec-
tion were investigated on PVY (strain Y
Boosting the Immune System of Solanaceous Plants
S. G. Spivak*, M. A. Kisel*, and G. A. Yakovleva**
*Institute of Bioorganic Chemistry, National Academy of Sciences of Belarus,
ul. Akad. Kuprevicha 5/2, Minsk, 220141 Belarus;
fax: (375) 264-8761; e-mail: firstname.lastname@example.org
**Potato Institute, National Academy of Sciences of Belarus, Samokhvalovichi, Minsk oblast, Belarus
Received September 7, 2001
treatment of solanaceous plants, viz. potato (
L.) and tobacco (
L.), with lysophosphatidylcholine promoted their resistance to phytopathogens, such as
(Mont.) de Bary and potato virus Y. The systemic and long-term lysophospholipid-induced
response was independent of the phytopathogen type. It was concluded that lysophosphatidylcholine, a product
of phosphatidylcholine hydrolysis with phospholipase A
, plays an important role in the regulation of plant
Key words: Solanum tuberosum - Nicotiana tabacum - Phytophthora infestans - potato virus Y - lysophosphati-
dylcholine - arachidonic acid - immune system
: AA—arachidonic acid; HSR—hypersensitive
response; IEA—immunoenzyme analysis; LPC—lysophosphati-
dylcholine; PVY—potato virus Y.