BIODIVERSITY OF COTTON RHIZOSPHERE BACTERIA N.A. Sherbekova 1 , Q.T. Normurodova 1 , S.I. Zakiryayeva 2 1) National University of Uzbekistan named after Mirzo Ulugbek, 100174, Tashkent, Uzbekistan 2) Institute of Microbiology, AS of Uzbekistan, 100128, Tashkent, Uzbekistan One of the important issues that need to be solved in the whole world today is to
provide the world's population with quality food and quality clothing products.
Cotton plant is grown in a lot of countries around the world. Cotton fiber serves as an
important natural textile fiber, and also cottonseed is an important source of food and
oil.
The interaction of plants with symbiotic and beneficial rhizobacteria microorganisms
is important in the development of plants because it provides them with appropriate
nutrition and regulators, protects them from pathogenic microorganisms, and adapts
them to stressful conditions. It is no secret that in most cases, the qualitative description
of the arable layer determines the activity of the soil microflora.
Therefore, the purpose of the research is to study the diversity of cotton rhizosphere
bacteria grown in saline soils of Syrdarya region in Uzbekistan.
During the conducted research, cotton rhizosphere samples were brought from
Gulistan district of Syrdarya region in spring, summer, and autumn seasons and their
biodiversity was studied. As a result, more than 30 strains of rhizobacteria were
isolated from cotton rhizosphere. 15 cultures were isolated from the spring season, 10
from the summer season, and 12 from the autumn season. The morpho-cultural
characteristics of these cultures were studied and identified using the MALDI TOF
mass-spectrometry method.
As a result of studying the size, mobility, shape, and size of colonies, optical
properties, color, surface layer, edges, structure, and consistency of each isolated
bacterial strain, it was determined that they belong to the genera
Enterobacter, Bacillus and
Lactobacillus . At the same time, the strains of rhizobacteria were studied to the type
using MALDI TOF mass-spectrometry method, and as a result, 3 of the rhizobacterial
cultures were
Enterobacter cloacae and
Bacillus cereus , one of them was
Lactobacillus malefermentans, B. wakoensis, B. subtilis, B. megaterium and
Cedecea davisae, and two
strains were
B. simplex , five ones were found to belong to
B. endophyticus species. Enterobacter cloacae was found as the dominant species in cotton rhizosphere in the
spring season, while
B. endophyticus was the dominant species in the summer season.
To conclude, more than 30 strains of rhizobacteria were isolated from the cotton
rhizosphere in spring, summer, and autumn, and as a result of their identification using
the MALDI TOF mass-spectrometry method, it was found that 3 of them belong to the
genera
Enterobacter , 13 to
Bacillus, 1 to
Lactobacillus and
Cedecea. It was observed
that Enterobacter cloacae species were abundant in cotton rhizosphere in spring.
B. endophyticus species were found throughout the season.