ISSN 10214437, Russian Journal of Plant Physiology, 2015, Vol. 62, No. 6, pp. 715–726. © Pleiades Publishing, Ltd., 2015.
Original Russian Text © I.V. Maksimov, S.V. Veselova, T.V. Nuzhnaya, E.R. Sarvarova, R.M. Khairullin, 2015, published in Fiziologiya Rastenii, 2015, Vol. 62, No. 6, pp. 763–775.
Plants are constantly exposed to stress factors of
biotic and abiotic nature. The improvement of plant
resistance to pathogens is an urgent task aimed at the
creation of effective systems of plant protection. It can
be solved through deep understanding of plant and
pathogen physiology and their interactions. Modern
technologies of crop cultivation often include obliga
tory treatments conferring protection against diseases,
such as seed surface sterilization and spraying the
seedlings with pesticides. Since these methods of plant
protection are environmentally unsafe, further
improvement of crop protection chemicals (CPC) and
creation of their less toxic analogs are needed.
The global trend toward the decrease in application
rates of agrochemicals determines the demand from
the plant growing industry for novel sources of mineral
nutrition and biological crop protection products.
Recently, the increasing attention of scientists has
been focused on biological products based on plant
growthpromoting bacteria (PGPB) . Endophytic
bacteria that live mutualistically in plant tissues are
particularly interesting, because they are less depen
dent on environmental factors compared to other
microorganisms and, at the same time, they exhibit a
range of economically useful properties. Once in plant
tissues, endophytes may promote the longterm pro
tection of host against environmental stress factors .
Currently, the Ministry of Agriculture of the Rus
sian Federation registered 15 plant protection bio
products, based on live bacteria, for the purpose of
pest control and agrochemical treatments. Twelve of
them are biofungicides (PhytosporinM, AlirinB,
Baktofit, Gamair, Vitaplan, Bisolbisan, Elena, Bino
ram, Rhizoplan, Extrasol, etc.) and three are insecti
cides (Bitoxibacillin, lepidobactocid, lepidocid).
Despite this wide assortment, there are no effective
biofungicides capable of protecting grain crops against
pathogens of numerous diseases, such as leaf rust,
powdery mildew, septoria spot, and solid and loose
smut. The development of pest control preparations
on the basis of endophytes is hampered, in our view, by
the lack of systematic studies on molecular interac
tions in plant–PGPB or plant–PGPB–phytopatho
gen (pest) systems.
POTENTIAL OF PGPB IMPLEMENTATION
IN BIOLOGICAL PREPARATIONS
Crop protection chemicals—insecticides and fun
gicides—are widely used for plant protection against
diseases and pests, because they are generally more
effective than biological preparations. However, a pos
sible negative impact of pesticides on the environment
Plant GrowthPromoting Bacteria in Regulation of Plant Resistance
to Stress Factors
I. V. Maksimov, S. V. Veselova, T. V. Nuzhnaya, E. R. Sarvarova, and R. M. Khairullin
Institute of Biochemistry and Genetics, Ufa Research Center, Russian Academy of Sciences,
pr. Oktyabrya 71, Ufa, 450054 Russia
Received March 3, 2015
—The review considers the mechanisms underlying the ability of plant growthpromoting bacteria
(PGPB) to enhance plant tolerance to biotic and abiotic stresses. The improved tolerance is determined by a
number of microbiological factors such as: supply of mineral nutrients; production of hormones and signaling
metabolites; syntheses of antibiotics, biosurfactants, siderophores, chitinases, glucanases, proteases and lipases
and other defence proteins; and induction of plant systemic resistance to pathogens and herbivores. Possible
mechanisms of interactions in the plant–PGPB–pathogen (pest) system are considered. The PGPB may exert
their role either directly, through elimination of harmful organisms by antimicrobial substances and hydrolytic
enzymes, or indirectly, through activation of host defense systems and the induction of systemic resistance. New
approaches to the design of broadspectrum biopesticides on the basis of PGPB are considered.
: plant growthpromoting microorganisms, biotic and abiotic stresses, systemic resistance, plant
: CLPs—cyclic lypopeptides; CPC—crop protec
tion chemicals; JA—jasmonic acid; HM—heavy metals; ISR—
induced systemic resistance; PGPB—plant growthpromoting
bacteria; PRgenes—pathogenesisrelated (genes); SA—salicylic
acid; SAR—systemic acquired resistance.