ISSN 2305-9397. Ғылым және білім. 2022. № 3-3 (68)____ _
169
Shamekova M.Kh., PhD,
https://orcid.org/0000-0002-8746-7484
Institute of Plant Biology and Biotechnology, Almaty, 050040, Timiryazev street 45, Kazakhstan,
shamekov@gmail.com
BACTERIAL DISEASES OF CEREALS IN KAZAKHSTAN
ANNOTATION
Environmental and genetic monitoring of pathogens of the most dangerous bacterial diseases
of wheat and other cereal crops was carried out - pathogens of black (Xanthomonas campestris) and
basal (Pseudomonas syringae) bacterioses of wild and agricultural cereal crops. In total, 93 plant
samples of cereal crops were collected in the west and north of Kazakhstan with symptoms of bacterial
diseases and 120 DNA samples were isolated. Molecular screening of pathogens of bacterial diseases
using specific markers showed the presence of pathogens of basal and black bacteriosis and their
pathovars in the northern region of Kazakhstan. Bacterioses infecting cereals were identified using the
ITS region sequences. The causative agent of basal bacteriosis (Pseudomonas syringae) was identified
in samples from the Karaganda, Kostanay, and Akmola regions, which was confirmed by the results of
sequencing of the species-specific genome region of this bacterium. Research on the development of a
method for identifying bacterioses of cereal crops based on molecular methods is new for Kazakhstan
and the world community.
Key words: wheat, wild cereals, bacterial diseases, pathogen potavars, bacterial leaf streak,
basal glume rot.
Introduction. Agricultural cereals, including wheat, are affected by bacterial diseases, the
causative agents of which infect many wild cereals, which complicates the effective protection of
crops from pathogens. The causative agents are rod-shaped bacteria belonging to the genera
Pseudomonas, Xanthomonas, and Bacillus. In the Central Chernozem Zone of Russia and Kazakhstan
on winter wheat, there are 3 types of bacterial diseases (bacteriosis) - black, basal, and brown, which
differ in symptoms and species composition of pathogens [1, 2].
The causative agent of basal bacteriosis (basal glume rot) is the bacteria Pseudomonas
syringae pv. atrofaciens [3]. Symptoms of the disease on the spikelets appear at the base of the scales
in the form of translucent spots. With a strong development of the disease, symptoms of infection are
observed as blackening and deformation of the entire ear and formation of a puny grain. Seedlings
from affected seeds lag in growth and often die. The disease is common on winter and spring wheat in
regions with a fairly humid climate. The yield of plants affected by black bacteriosis can decrease
from 15 to 90%. Infected seeds and crop leavings are the main sources of infection transmission,
where the pathogen survives until the following year [4]. The bacterium Pseudomonas syringae van
Hall, which also affects sorghum, Sudan grass, corn, and millet, was identified to produce bacterial
spotting in spring wheat in the Akmola region [5].
The cause of bacterial leaf streak (BLS), Xanthomonas campestris pv. translucens, manifests
as watery patches on the leaves that later turn brown. This gram-negative bacterium can cause
significant illnesses in crops and forage grasses. Pathovars in the translucens group are the source of
bacterial leaf streak (BLS) in cereals such wheat, barley, triticale, rye, and oats [6].
In recent years, BLS has again become a serious problem for many regions of the world
producing wheat and barley. Pathogen biology and host-pathogen interactions in cereal BLS diseases
have been poorly understood. Nevertheless, recent genome sequence data has provided insight into
bacterial phylogeny, identification, and pathogenicity/virulence [7]. Moreover, identification of
sources of resistance to BLS and mapping of resistance genes was initiated. In 2002, for the first time,
a noticeable lesion of spring wheat with a bacterial leaf streak was detected in the Akmola region.
Later, it was found in the
Pilont Plant Facility
«Zarechnoye» of the Kostanay Research Institute of
Agriculture on the Omskaya 24 variety, and barley, which was heavily affected by the disease. In
2005, bacterial leaf streak was found in the Taiynshinsky and Akkayynsky districts of the North
Kazakhstan region on the wheat varieties Omskaya 19, Astana, Astana 2, and Pamyati Aziyeva. Its
noticeable development took place in 2007-2008 and 2015 on the crops of the experimental station
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