American Journal of Applied Science and Technology
44
https://theusajournals.com/index.php/ajast
VOLUME
Vol.05 Issue 06 2025
PAGE NO.
44-56
10.37547/ajast/Volume05Issue06-10
Characteristics And Research Approaches To Plant
Microbiomes In The Ecological Conditions Of The
Kyzylkum Desert
B.Toshbadalov
Institute of Fundamental and Applied Research, National Research University, Tashkent, Uzbekistan
Received:
14 April 2025;
Accepted:
10 May 2025;
Published:
18 June 2025
Abstract:
The Kyzylkum Desert represents a unique and extreme ecosystem where plants depend critically on their
associated microbiomes for survival and adaptation. This review explores the intricate composition, dynamic
interactions, and functional roles of plant microbiomes in such harsh environments, emphasizing their ecological
importance and potential applications. Despite significant progress in microbiome research, major gaps remain in
understanding the specific mechanisms that enable these microbial communities to thrive under extreme abiotic
stressors like high salinity, nutrient deficiency, and drought. Advanced molecular approaches, including
metagenomics and 16S rRNA sequencing, are highlighted as indispensable tools for unraveling microbial diversity
and functionality in desert ecosystems.
Key findings reveal the vital roles of microbial communities
—
bacteria, fungi, actinomycetes, and archaea
—
in
enhancing nutrient acquisition, improving drought resilience, and mitigating oxidative stress in desert plants.
Notably, symbiotic associations such as nitrogen-fixing bacteria, phosphate-solubilizing fungi, and arbuscular
mycorrhizal fungi are crucial in facilitating plant survival in the nutrient-poor soils of the Kyzylkum Desert.
Furthermore, this review underscores the unique adaptive traits of desert microbiomes, including stress-response
proteins, exopolysaccharide production, and osmoprotectants, which collectively sustain plant-microbe
interactions under challenging conditions.
This review integrates findings from local and international research to bridge critical knowledge gaps and
underscores the potential of desert microbiomes for sustainable applications, including bioinoculants, soil health
enhancement, and desertification mitigation. These insights pave the way for innovative strategies to harness
microbial communities in addressing global challenges in agriculture and ecosystem restoration.
Keywords:
Kyzylkum Desert, plant microbiome, microbial diversity, metagenomics, bioinoculants, plant-microbe
interactions, desert ecology, microbial adaptation, desertification control, sustainable agriculture.
Introduction:
The Kyzylkum Desert, one of Central Asia's largest arid
regions,
is
characterized
by
its
extreme
environmental
conditions,
including
high
temperatures, minimal annual rainfall (less than 100
mm), and highly saline, nutrient-poor soils. Despite
these harsh conditions, plants in the Kyzylkum Desert
have developed intricate ecological relationships with
their microbiomes, which are crucial for their survival
[1].
Plant
microbiomes,
consisting
of
soil
microorganisms, fungi, bacteria, and archaea, play
essential roles in plant growth, stress tolerance, and
nutrient acquisition [2]. In extreme environments
such as the Kyzylkum Desert, these microbial
communities are vital for plant resilience against
salinity, drought, and nutrient limitations, making
them indispensable for the ecosystem's sustainability
[3]. However, research on the microbiomes in the
Kyzylkum Desert remains limited, leaving significant
gaps in understanding their biodiversity, functional
roles, and adaptation mechanisms. Advanced
molecular technologies, including metagenomics and
16S rRNA sequencing, are powerful tools to elucidate
the biological and ecological significance of these
microbiomes [4].
The primary objective of this study is to
American Journal of Applied Science and Technology
45
https://theusajournals.com/index.php/ajast
American Journal of Applied Science and Technology (ISSN: 2771-2745)
investigate the composition, ecological functions, and
adaptation mechanisms of plant microbiomes in the
Kyzylkum Desert. By addressing these critical research
gaps, this study aims to contribute to a deeper
understanding of desert ecosystems and provide
innovative solutions for sustainable agriculture, such as
bioinoculants and soil improvement strategies [5].
The Kyzylkum Desert, as one of the largest arid
regions in Central Asia, harbors a unique and diverse
range of microbiomes adapted to its harsh
environmental
conditions.
These
microbiomes,
comprising bacteria, fungi, actinomycetes, and
archaea, play a crucial role in maintaining ecosystem
functionality and ensuring plant survival in nutrient-
poor and saline soils. This section explores the diversity
of microbial communities in the desert, highlighting
their composition, adaptations, and ecological
significance.
Microbial Communities in the Kyzylkum Desert
1.
Bacteria:
Bacteria represent the most abundant and versatile
group in desert microbiomes. Species belonging to the
genera
Bacillus
,
Pseudomonas
, and
Azospirillum
are
particularly notable. These bacteria contribute to
nutrient cycling, nitrogen fixation, and stress
resistance. Nitrogen-fixing bacteria like
Rhizobium
and
Azospirillum
enhance soil fertility by converting
atmospheric nitrogen into plant-available forms, a
critical process in nitrogen-deficient desert soils [6].
2.
Fungi:
Fungi, especially phosphate-solubilizing species such as
Aspergillus
and
Penicillium
, play a vital role in nutrient
mobilization. They secrete organic acids and enzymes
that solubilize insoluble phosphates, making them
available for plant uptake. Arbuscular mycorrhizal (AM)
fungi, such as
Glomus
and
Funneliformis
, form
symbiotic associations with plant roots, enhancing
nutrient and water absorption in arid soils [7].
3.
Actinomycetes:
Actinomycetes, particularly
Streptomyces
species, are
known for their ability to produce secondary
metabolites such as antibiotics and growth-promoting
compounds. These metabolites help plants combat
pathogens and adapt to abiotic stresses like drought
and salinity.
Streptomyces
spp. are abundant in the
Kyzylkum Desert and play a pivotal role in soil health
[8].
4.
Archaea:
Although less studied, archaea in the Kyzylkum Desert
exhibit remarkable adaptations to extreme salinity and
temperature fluctuations. Halophilic archaea, such as
Halobacterium
spp., are crucial for osmotic balance and
nutrient cycling in saline environments [9].
The genetic diversity of desert microbiomes is
vast, with numerous genes encoding for stress-
response proteins, secondary metabolite production,
and nutrient acquisition mechanisms. Metagenomic
studies have revealed genes responsible for the
synthesis of osmoprotectants like glycine betaine and
trehalose, which help microorganisms survive
desiccation and salinity [10]. Functional diversity is
equally significant, as these microorganisms perform
critical roles in nutrient cycling, including carbon,
nitrogen, and phosphorus fluxes, which are essential
for sustaining plant life in arid ecosystems.
Microbial diversity in the Kyzylkum Desert is
influenced by seasonal changes, soil type, and plant
species. During dry seasons, microbial communities
exhibit enhanced production of stress-related
compounds, while wet seasons promote microbial
proliferation and activity
[ref bo’lsa qo’ying]
. Different
plants host unique microbiomes, reflecting a high
degree of habitat specificity. For example, halophilic
bacteria dominate in plants like
Haloxylon spp.
,
whereas phosphate-solubilizing fungi are prevalent in
Salsola spp.
[11].
The ecological significance of microbial
diversity in the Kyzylkum Desert cannot be overstated.
These microbiomes are indispensable for plant survival,
particularly in nutrient-poor soils. They facilitate
nutrient acquisition, improve soil structure, and
provide resilience against abiotic stresses [ref].
Furthermore, microbial communities contribute to the
desert's overall ecosystem stability by driving
biogeochemical cycles and supporting vegetation cover
[12].
Despite their importance, the microbiomes of
the Kyzylkum Desert remain underexplored. Challenges
such as the harsh environment, limited accessibility,
and lack of advanced research facilities hinder
comprehensive studies. Understanding the diversity
and functionality of these microbiomes requires the
integration of traditional microbiological techniques
with modern molecular approaches like metagenomics
and transcriptomics [13].
Future
research
should
prioritize
the
characterization of novel microbial species and their
ecological roles. Identifying and harnessing stress-
resilient microorganisms can pave the way for
sustainable applications in agriculture, such as the
development of bioinoculants and biostimulants
tailored
to
arid
environments.
Additionally,
comparative studies across different arid regions can
provide broader insights into the adaptive mechanisms
of desert microbiomes and their potential in combating
desertification [14].
The plant microbiomes in the Kyzylkum Desert
perform vital ecological functions that sustain plant life
in extreme environmental conditions. These functions
include nutrient acquisition, stress alleviation,
American Journal of Applied Science and Technology
46
https://theusajournals.com/index.php/ajast
American Journal of Applied Science and Technology (ISSN: 2771-2745)
biocontrol mechanisms, and contributions to overall
ecosystem stability. This section explores the specific
roles of these microbiomes and their impact on desert
ecosystems.
Role in Nutrient Acquisition
1.
Nitrogen
Fixation:
Microbial
communities, particularly nitrogen-fixing bacteria like
Rhizobium
and
Azospirillum
, are crucial for improving
soil fertility in nitrogen-deficient soils. These microbes
convert atmospheric nitrogen into plant-available
ammonium through nitrogenase activity, addressing
one of the primary nutrient limitations in arid
environments [15].
2.
Phosphate Solubilization: Phosphate is
often unavailable in desert soils due to its fixation in
insoluble forms. Phosphate-solubilizing microbes, such
as
Aspergillus
and
Penicillium
species, secrete organic
acids and phosphatases that mobilize these bound
phosphates, making them accessible to plants [16].
3.
Enhancement
of
Micronutrient
Uptake: Microorganisms like siderophore-producing
bacteria (e.g.,
Pseudomonas
spp.) chelate essential
micronutrients such as iron, zinc, and manganese,
enhancing their bioavailability for plant uptake [17].
Stress Alleviation
1.
Abiotic Stress Mitigation:
o
Microbiomes alleviate drought stress
by producing osmoprotectants like proline and
trehalose, which help plants maintain cellular integrity
and water balance under limited water availability [18].
o
Rhizosphere
bacteria
secrete
exopolysaccharides that improve soil aggregation and
moisture retention, providing a stable environment for
plant roots [19].
2.
Salinity
Tolerance:
Halotolerant
microbes, such as
Bacillus
and
Microbacterium
species,
aid in osmotic balance by producing compatible solutes
and enzymes that combat ionic stress. These
adaptations are crucial for plant survival in saline soils
typical of the Kyzylkum Desert [20].
Biocontrol Mechanisms
1.
Pathogen
Suppression:
Beneficial
microbes act as natural biocontrol agents by inhibiting
plant pathogens. For example,
Pseudomonas
and
Bacillus
species produce antimicrobial compounds like
antibiotics, lipopeptides, and siderophores that restrict
pathogen proliferation [21].
2.
Induced Systemic Resistance (ISR):
Certain rhizosphere bacteria and fungi prime plants for
defense against biotic stress by triggering ISR, which
enhances the plant’s ability to resist subsequent
pathogen attacks [22].
3.
Protection
Against
Herbivores:
Microbes contribute to plant defense against
herbivorous pests by producing volatile organic
compounds (VOCs) that deter insects and enhance
plant resistance [23].
Contribution to Ecosystem Stability
1.
Nutrient
Cycling:
Microbial
communities play a central role in cycling key nutrients
like nitrogen, phosphorus, and carbon, ensuring their
availability for plant and microbial use. These cycles are
essential for maintaining the functional integrity of
desert ecosystems [24].
2.
Soil Fertility and Structure:
o
Microbial exudates, including glomalin
secreted by arbuscular mycorrhizal fungi, improve soil
structure and stability, reducing erosion risks.
o
These activities enhance the water-
holding capacity and nutrient availability of soils,
promoting vegetation cover [25].
3.
Resilience Against Desertification:
Microbiomes contribute to ecosystem stability by
supporting plant growth and vegetation cover,
mitigating desertification processes and enhancing the
resilience of arid landscapes [26].
Despite significant progress in understanding
the ecological functions of microbiomes, gaps remain
in elucidating their full potential in arid regions like the
Kyzylkum Desert. Future research should focus on
integrating molecular and ecological studies to uncover
the specific interactions between plants and their
microbiomes. Additionally, exploring the use of
microbiomes in developing bioinoculants and
sustainable agricultural practices could significantly
benefit desert ecosystems [27].
Table 1. Key Microbial Groups and Their Functional Roles in the Kyzylkum Desert Ecosystem
Microbial
Group
Dominant Genera
Functional Role
Adaptation to Desert
Conditions
Reference
Nitrogen-Fixing
Bacteria
Rhizobium
,
Azospirillum
Fixation of
atmospheric nitrogen
into bioavailable
forms for plants
Production of stress-
tolerant enzymes and
nitrogenase activity under
low moisture levels
Vessey (2003);
Bashan et al.
(2004)
Phosphate-
Solubilizing
Fungi
Aspergillus
,
Penicillium
Solubilization of
insoluble phosphates
to increase
Secretion of organic acids
and phosphatases
Khan et al.
(2010); Mora-
Ruiz et al. (2016)
American Journal of Applied Science and Technology
47
https://theusajournals.com/index.php/ajast
American Journal of Applied Science and Technology (ISSN: 2771-2745)
phosphorus
availability in soil
Halophilic
Bacteria
Bacillus
,
Microbacterium
Water retention and
osmotic balance in
saline environments
Exopolysaccharide
production and synthesis
of osmoprotectants
Ruppel et al.
(2013); Oren
(2011)
Mycorrhizal
Fungi
Glomus
,
Funneliformis
Enhanced nutrient
absorption and soil
stabilization
Formation of extensive
hyphal networks and
secretion of glomalin
Egamberdieva et
al. (2015); Singh
et al. (2021)
Actinomycetes
Streptomyces
,
Micromonospora
Production of
bioactive compounds
and plant growth
promotion
Synthesis of antibiotics
and secondary
metabolites
Sathya et al.
(2017); Gonzalez
et al. (2018)
Endophytic
Bacteria
Pseudomonas
,
Bacillus
Biocontrol against
plant pathogens
through antimicrobial
compound
production
Siderophore secretion to
limit pathogen access to
essential nutrients
Hartmann et al.
(2014); Gonzalez
et al. (2018)
Table 1 summarizes the key microbial groups found in
the Kyzylkum Desert and their functional roles in
supporting plant survival and maintaining ecosystem
stability. The table highlights their dominant genera,
primary ecological functions, and the specific
adaptations that enable their survival in extreme desert
conditions.
For instance, nitrogen-fixing bacteria such as
Rhizobium
and
Azospirillum
enhance soil nitrogen
availability, while phosphate-solubilizing fungi like
Aspergillus
and
Penicillium
address phosphorus
limitations
through
solubilization
mechanisms.
Additionally, halophilic bacteria and mycorrhizal fungi
contribute to osmotic regulation and nutrient uptake,
respectively. These functional roles underscore the
critical contribution of microbial communities to desert
ecosystem resilience.
Such findings emphasize the need for further
exploration of these microbial groups, particularly their
genetic and metabolic capabilities, which could have
significant
implications
for
biotechnological
applications and sustainable agriculture in arid
environments.
Microbial communities in the Kyzylkum Desert have
developed remarkable adaptation mechanisms to
survive and thrive under extreme environmental
stressors, including high temperatures, salinity, and
nutrient scarcity. This section delves into the
physiological, biochemical, and genetic adaptations of
these microbiomes, illustrating their resilience and
ecological importance.
Physiological Adaptations
1.
Exopolysaccharide (EPS) Production: Many desert
microbes produce exopolysaccharides, which
improve soil aggregation and help retain moisture
around plant roots. This adaptation is particularly
crucial in the sandy, porous soils of the Kyzylkum
Desert, where water is a limiting factor [28]. EPS
also facilitates microbial adhesion to plant roots,
enhancing nutrient exchange.
2.
Osmoprotectant Synthesis: Microbial synthesis of
osmoprotectants like proline, glycine betaine, and
trehalose is a key adaptation to salinity and
drought. These compounds stabilize cellular
proteins and membranes, preventing damage from
osmotic stress caused by high salt concentrations
in the soil [29].
3.
Heat-Shock Proteins (HSPs): Heat-shock proteins
protect microbial cells from damage during
extreme temperature fluctuations. These proteins
refold denatured proteins and ensure cellular
functionality under heat stress, a frequent
condition in desert ecosystems [30].
Biochemical Adaptations
1.
Production of Antioxidative Enzymes: Reactive
oxygen species (ROS) accumulate under abiotic
stresses like drought and salinity. Desert microbes
produce antioxidative enzymes such as superoxide
dismutase (SOD) and catalase, which neutralize
ROS and protect cellular components from
oxidative damage [31].
2.
Secondary Metabolites: Actinomycetes, especially
Streptomyces
species, produce a wide range of
secondary metabolites, including antibiotics and
siderophores. These metabolites not only protect
microbes from competitors but also enhance plant
growth by inhibiting pathogens and increasing iron
availability [32].
3.
Pigment Production: Carotenoids and melanin are
common pigments synthesized by desert microbes.
These pigments protect cells from ultraviolet (UV)
American Journal of Applied Science and Technology
48
https://theusajournals.com/index.php/ajast
American Journal of Applied Science and Technology (ISSN: 2771-2745)
radiation, a significant stressor in open desert
environments. They also play roles in ROS
scavenging and membrane stabilization [33].
Genetic Adaptations
1.
Stress-Responsive
Genes:
Desert
microbes possess genes encoding for proteins that
confer resistance to abiotic stresses. For example,
genes involved in the synthesis of osmoprotectants,
EPS, and HSPs are upregulated in response to
environmental triggers [34].
2.
Horizontal Gene Transfer (HGT):
Horizontal gene transfer is a common mechanism
among desert microbes, enabling the rapid acquisition
of stress-resistance traits. This genetic exchange
fosters
microbial
community
resilience
and
adaptability [35].
3.
Unique
Genomic
Features:
Comparative genomics reveals that desert microbes
have smaller, streamlined genomes with a high
proportion of genes dedicated to stress tolerance and
resource efficiency. These adaptations reflect
evolutionary
pressures
in
resource-scarce
environments like the Kyzylkum Desert [36].
Microbial adaptation mechanisms in the
Kyzylkum Desert show striking similarities with those
observed in other arid regions worldwide, such as the
Atacama and Thar Deserts. Shared traits include EPS
production,
osmoprotectant
synthesis,
and
antioxidative enzyme activity. However, unique
adaptations in the Kyzylkum Desert, such as the
prevalence of halophilic bacteria, highlight the
ecological specificity of this region [37].
Ecological and Practical Significance
1.
Plant Resilience: These adaptations directly benefit
desert plants by improving nutrient availability,
water retention, and stress tolerance. For instance,
mycorrhizal fungi extend plant root networks,
enhancing water and nutrient uptake even in saline
soils [38].
2.
Soil Stability: EPS production and microbial
exudates improve soil structure, reducing erosion
and enhancing fertility. This contributes to desert
ecosystem
sustainability
and
mitigates
desertification [39].
3.
Potential
for
Agricultural
Applications:
Understanding microbial adaptations can inform
the
development
of
bioinoculants
and
biostimulants tailored for arid agriculture. These
products could enhance crop productivity in saline
and drought-prone soils [40].
Further exploration of the genetic and
biochemical
pathways
underlying
microbial
adaptations is necessary to unlock their full potential.
Integrating metagenomics, transcriptomics, and
proteomics will provide deeper insights into microbial
resilience. Additionally, field studies comparing
microbial communities across different microhabitats
within the Kyzylkum Desert can reveal novel adaptive
traits [41].
The unique adaptations and functional roles of
microbiomes in the Kyzylkum Desert open significant
opportunities for practical applications in agriculture,
biotechnology, and ecological restoration. Harnessing
these microbial communities can address challenges
such as soil degradation, desertification, and climate
change impacts on agriculture.
Bioinoculants for Sustainable Agriculture
1.
Nitrogen Fixation and Soil Fertility Improvement:
Nitrogen-fixing bacteria such as
Azospirillum
and
Rhizobium
can be developed into bioinoculants to
improve nitrogen availability in nutrient-deficient
soils. These bioinoculants reduce the dependency
on chemical fertilizers, promoting eco-friendly
agricultural practices [42].
2.
Phosphate Solubilization for Crop Enhancement:
Microbial strains such as
Aspergillus
spp. and
Bacillus
spp. can solubilize bound phosphate in arid
soils, making it available to plants. These
bioinoculants
enhance
plant
growth
and
productivity in phosphorus-limited environments
[43].
3.
Stress
Tolerance
Promotion:
Microbial
bioinoculants producing osmoprotectants like
proline and trehalose can improve plant resilience
against drought and salinity, ensuring sustainable
crop yields in arid regions [44].
Bioremediation and Soil Restoration
1.
Improving Soil Structure: Exopolysaccharide-
producing microbes enhance soil aggregation and
stability. Their application in degraded lands can
prevent erosion and restore soil fertility, crucial for
combating desertification in the Kyzylkum Desert
[45].
2.
Halophilic Microbial Consortia: Halophilic and
halotolerant
microbes
can
be
used
for
phytoremediation of saline soils, improving soil
health and enabling the cultivation of salt-tolerant
crops [46].
Development of Drought-Resistant Crops
1.
Mycorrhizal
Fungi
for
Water
Uptake:
Arbuscular mycorrhizal (AM) fungi, such as
Glomus
spp., enhance root water absorption by extending
the root network into deeper soil layers. This
symbiosis increases the drought resistance of
crops, particularly in arid zones like the Kyzylkum
Desert [47].
2.
Gene Transfer Technology: Understanding the
genetic basis of stress tolerance in desert microbes
American Journal of Applied Science and Technology
49
https://theusajournals.com/index.php/ajast
American Journal of Applied Science and Technology (ISSN: 2771-2745)
can inform genetic engineering approaches to
develop drought-resistant crops. Genes encoding
osmoprotectants and antioxidative enzymes can
be transferred to crop plants, improving their
performance under abiotic stress [48].
Eco-Friendly Pest Management
1.
Biological Control Agents: Desert
microbes such as
Bacillus
and
Pseudomonas
species
produce antimicrobial peptides and volatile organic
compounds (VOCs) that suppress plant pathogens and
herbivorous pests. These microbes can serve as eco-
friendly alternatives to chemical pesticides [49].
2.
Induced Systemic Resistance (ISR):
Certain
microbial strains can prime plants’ immune
systems, enhancing their natural defenses against
biotic stressors. ISR-inducing microbes reduce the
incidence of diseases in crops while minimizing
environmental impacts [50].
Combating Desertification
1.
Vegetation Restoration: Microbial
consortia from the Kyzylkum Desert can support the
growth of native desert plants, stabilizing soil and
promoting vegetation cover. This approach mitigates
desertification and improves ecosystem health [51].
2.
Carbon
Sequestration:
Microbial
activity in desert soils contributes to carbon cycling,
capturing atmospheric CO2 and storing it in soil organic
matter. This process has implications for global climate
change mitigation efforts [52].
Despite
these
promising
applications,
significant knowledge gaps remain regarding the
scalability and long-term impacts of utilizing desert
microbiomes in agriculture and environmental
restoration. Future studies should focus on field trials,
cost-effective production methods for bioinoculants,
and understanding the ecological balance of
introduced microbial strains [53].
Table 2. Functional Roles and Adaptation Mechanisms of Microbial Groups in the Kyzylkum Desert
Microbial Group
Primary Ecological Roles
Adaptation Mechanisms to Desert Conditions
Bacteria
Rhizobium
,
Azospirillum
Nitrogen fixation, enhancing soil
fertility
Utilizing nitrogenase enzyme to assimilate
atmospheric nitrogen
Bacillus
,
Pseudomonas
Biocontrol against pathogens,
siderophore production
Exopolysaccharide production, osmoprotectants
(trehalose, proline)
Microbacterium
Phosphorus mobilization,
solubilizing phosphates in the soil
Production of organic acids
Fungi
Aspergillus
,
Penicillium
Mobilizing phosphorus and
micronutrients
Exopolysaccharide production, hydrolytic
enzymes
Glomus
(arbuscular
mycorrhizae)
Enhancing water and nutrient
uptake
Symbiotic integration into root cells, creating an
extensive root network
Actinomycetes
Streptomyces
Producing antibiotics,
suppressing pathogens
Production of secondary metabolites (antibiotics,
siderophores)
Archaea
Halobacterium
Ion balance and stress tolerance
Producing halophilic pigments, maintaining
osmotic balance via glycine-betaine and trehalose
Table 2 highlights the key microbial groups in the
Kyzylkum Desert, emphasizing their functional roles
and unique adaptations to extreme environmental
conditions. The table categorizes microbes into
bacteria,
fungi,
actinomycetes,
and
archaea,
showcasing their contributions to desert ecosystems:
1.
Bacteria:
Essential
for
nitrogen
fixation, phosphorus mobilization, and biocontrol
activities, bacteria like
Rhizobium
and
Bacillus
enhance
soil fertility and plant health. Their ability to produce
osmoprotectants and exopolysaccharides ensures
survival in saline and nutrient-poor soils.
2.
Fungi: Mycorrhizal fungi, particularly
Glomus
, form symbiotic associations with plant roots,
enhancing water and nutrient uptake. Phosphate-
solubilizing fungi like
Aspergillus
play a crucial role in
mobilizing bound nutrients, improving plant growth in
arid soils.
3.
Actinomycetes: Known for producing
secondary metabolites,
Streptomyces
species are vital
for pathogen suppression and improving soil health
through antibiotic and siderophore production.
4.
Archaea: Halophilic archaea like
Halobacterium
exhibit remarkable adaptations to
American Journal of Applied Science and Technology
50
https://theusajournals.com/index.php/ajast
American Journal of Applied Science and Technology (ISSN: 2771-2745)
salinity, utilizing pigments and osmotic regulators to
maintain cellular stability under extreme conditions.
These microbial groups collectively support plant
resilience and soil sustainability in the Kyzylkum Desert,
offering potential applications in bioinoculant
development, soil restoration, and sustainable
agriculture.
Plant microbiomes play a critical role in enhancing plant
health, nutrient acquisition, stress tolerance, and soil
fertility. The integration of plant-microbe interactions
into sustainable agriculture has become a focal point in
recent research. The diverse contributions of beneficial
microbes, such as nitrogen-fixing bacteria, phosphate-
solubilizing fungi, and endophytes, underline their
importance in improving crop productivity and
resilience under environmental stresses. The following
sections provide a detailed analysis of the
contributions, interactions, and applications of these
microbiomes, supported by an extensive div of
literature.
Nitrogen-fixing bacteria, including
Rhizobium
and
Azospirillum
, play a pivotal role in improving soil
fertility by converting atmospheric nitrogen into plant-
available
ammonium.
These
processes
are
fundamental in nitrogen-deficient soils, particularly in
arid and semi-arid regions [1],[14]. These bacteria
employ nitrogenase enzymes that operate under
anaerobic
conditions,
making
them
critical
components
of
symbiotic
relationships
with
leguminous
plants
[79].
Phosphate-solubilizing
microorganisms, such as
Aspergillus
and
Penicillium
,
complement nitrogen fixation by mobilizing insoluble
phosphates into bioavailable forms. These processes
enhance root growth and biomass production,
particularly in phosphorus-deficient soils [3],[39].
The integration of these microorganisms in
biofertilizers has shown promising results in
sustainable agriculture, reducing reliance on synthetic
fertilizers while improving crop yields [97],[45].
Furthermore, their symbiotic relationships with plant
roots enhance water and nutrient absorption, making
them indispensable for arid agriculture [46],[47].
Plant-associated
microbes
exhibit
remarkable
adaptations to abiotic stresses, including drought,
salinity,
and
temperature
fluctuations.
Exopolysaccharide (EPS) production by halotolerant
bacteria such as
Bacillus
and
Pseudomonas
enhances
soil aggregation, which improves water retention and
protects plants from osmotic stress [5],[16].
Additionally, osmoprotectants like proline and
trehalose, synthesized by these microbes which
stabilize cellular structures under saline conditions,
promoting plant survival in adverse environments
[13],[87].
Heat-shock proteins (HSPs) and antioxidative
enzymes, such as catalase and superoxide dismutase,
further contribute to microbial resilience under
extreme temperatures and oxidative stress conditions
[31],[32]. These adaptations are crucial for maintaining
ecosystem stability and enhancing plant resilience to
environmental challenges [9],[57].
The rhizosphere, the soil region surrounding
plant roots, harbors diverse microbial communities
that influence plant health and development. Studies
reveal that the composition and function of
rhizosphere microbiomes are shaped by plant
genotype, soil type, and environmental conditions
[89],[76]. Beneficial microbes, including rhizobacteria
and mycorrhizal fungi, facilitate nutrient cycling,
disease suppression, and stress tolerance, thereby
enhancing crop productivity [22],[73].
For instance, studies on maize and Arabidopsis
rhizosphere microbiomes demonstrate that specific
bacterial and fungal taxa play roles in modulating plant
immunity and nutrient acquisition [24],[90]. The
functional diversity of these microbial communities
underscores
their
importance
in
agricultural
ecosystems [35],[63].
Plant-associated
microbes,
particularly
those
producing antimicrobial compounds, play a vital role in
controlling
soilborne
pathogens.
Secondary
metabolites such as antibiotics, siderophores, and
lipopeptides, produced by
Streptomyces
and
Bacillus
species, suppress pathogen growth and enhance plant
immunity [93],[25]. Moreover, microbes that induce
systemic resistance (ISR) in plants, such as certain
strains of
Pseudomonas
, prepare plants for enhanced
defense against subsequent pathogen attacks
[87],[110].
The ability of microbes to modulate plant defense
mechanisms highlights their potential as biocontrol
agents. Their application in integrated pest
management (IPM) systems offers an eco-friendly
alternative
to
chemical
pesticides,
reducing
environmental and health risks [42],[104].
Bioinoculants and Sustainable Agriculture
The development of microbial consortia tailored for
specific crops and environmental conditions has
revolutionized sustainable agriculture. Bioinoculants
incorporating nitrogen-fixing, phosphate-solubilizing,
and stress-alleviating microbes have been shown to
improve crop yields and soil health in a cost-effective
manner [97],[105]. These formulations are particularly
beneficial in saline and nutrient-poor soils, where
conventional fertilizers are less effective [39],[47].
Mycorrhizal fungi, such as
Glomus
species,
have emerged as key players in enhancing root water
absorption and nutrient uptake in arid regions. Their
symbiotic associations with plants not only increase
drought resistance but also improve soil structure and
American Journal of Applied Science and Technology
51
https://theusajournals.com/index.php/ajast
American Journal of Applied Science and Technology (ISSN: 2771-2745)
fertility [38],[46].
Despite
the
significant
advances
in
understanding plant-microbe interactions, several gaps
remain. For instance, the specific signaling pathways
and genetic mechanisms underlying these interactions
require further exploration. Advanced molecular
techniques,
such
as
metagenomics
and
transcriptomics, hold promise for uncovering novel
microbial traits and their potential applications
[13],[67].
Field studies focusing on microbial community
dynamics and their interactions with plants under
varying environmental conditions will provide insights
into optimizing microbial applications in agriculture.
Additionally, efforts to scale up the production and
delivery of bioinoculants will be crucial for their
widespread adoption by farmers [53],[96].
Conclusion.
The literature highlights the
multifaceted roles of plant-associated microbiomes in
promoting sustainable agriculture and ecosystem
resilience. From nitrogen fixation and nutrient
mobilization to stress mitigation and disease
suppression, these microbes offer innovative solutions
for addressing the challenges of modern agriculture.
The integration of microbial technologies into farming
practices promises to enhance crop productivity while
preserving environmental health.
By leveraging the diverse functional attributes
of plant microbiomes, researchers and practitioners
can develop targeted strategies for improving
agricultural sustainability, combating desertification,
and mitigating the impacts of climate change.
Continued exploration of microbial diversity and
function will pave the way for novel applications,
bridging the gap between fundamental research and
practical implementation.
The microbiomes in the Kyzylkum Desert
exhibit remarkable adaptations and ecological roles
that are crucial for sustaining plant life and maintaining
soil health in extreme environmental conditions. This
discussion evaluates their unique features, practical
applications in agriculture and ecology, and potential
research directions.
Agricultural and Ecological Significance.
1.
Enhanced Soil Fertility: Microbial
communities, particularly nitrogen-fixing bacteria
(
Rhizobium
and
Azospirillum
), play a key role in
improving soil fertility. By converting atmospheric
nitrogen into bioavailable forms, these microbes
reduce dependency on synthetic fertilizers, promoting
sustainable agricultural practices in arid regions.
Similarly, phosphate-solubilizing fungi (
Aspergillus
and
Penicillium
) mobilize bound phosphates, enriching
nutrient-deficient
soils
and
enhancing
crop
productivity.
2.
Stress Mitigation for Plants: Desert
microbes produce osmoprotectants like trehalose and
proline, as well as exopolysaccharides that enhance
plant resilience to salinity and drought. For example,
arbuscular mycorrhizal fungi (
Glomus
spp.) form
symbiotic relationships with plants, improving water
and nutrient uptake. These stress-alleviating properties
can significantly increase the survival rate of crops in
arid and semi-arid regions.
3.
Combating Desertification: Microbial
communities contribute to ecosystem stability by
supporting vegetation growth and improving soil
structure. Exopolysaccharides produced by microbes
bind soil particles, reducing erosion and enhancing
water retention. These activities are pivotal for
mitigating desertification in fragile ecosystems like the
Kyzylkum Desert.
Potential for Developing Bioinoculants
1.
Custom
Bioinoculants
for
Arid
Agriculture:
The stress-resilient properties of desert microbiomes
can be harnessed to develop bioinoculants tailored for
arid regions. For instance:
o
Nitrogen-fixing
bacteria
and
phosphate-solubilizing fungi can be used to enhance
nutrient availability in poor soils.
o
Halotolerant
bacteria
(
Bacillus
,
Pseudomonas
) can improve crop growth in saline
conditions.
2.
Biocontrol Agents: Many desert
microbes produce antimicrobial compounds, such as
lipopeptides and siderophores, that suppress
pathogens. These properties can be utilized to develop
environmentally friendly biocontrol agents, reducing
the reliance on chemical pesticides.
3.
Soil Restoration: Microbial consortia
from the Kyzylkum Desert, especially those producing
exopolysaccharides, can be employed in soil
restoration projects. These bioinoculants could help
rehabilitate degraded lands and support sustainable
agriculture in marginal areas.
Future Research Directions
1.
Exploration of Microbial Diversity:
Despite significant progress, many microbial species in
the Kyzylkum Desert remain unidentified. Advanced
techniques
such
as
metagenomics
and
metatranscriptomics can be employed to uncover new
microbes with unique traits and their potential
applications in biotechnology and agriculture.
2.
Functional
Genomics
Studies:
Investigating the genes responsible for stress
tolerance, such as those encoding osmoprotectants
and antioxidative enzymes, can provide valuable
insights into microbial resilience. These studies can
American Journal of Applied Science and Technology
52
https://theusajournals.com/index.php/ajast
American Journal of Applied Science and Technology (ISSN: 2771-2745)
pave the way for engineering crops with improved
drought and salinity resistance.
3.
Microbial Interactions with Desert
Plants: Understanding the specific mechanisms of
plant-microbe
interactions,
including
signaling
pathways and symbiotic associations, can help
optimize the use of microbial consortia for enhancing
crop performance in arid ecosystems.
4.
Scaling Up Bioinoculant Production:
Translating laboratory findings into scalable solutions
remains a challenge. Future research should focus on
cost-effective production methods, storage, and
delivery systems for bioinoculants, ensuring their
widespread adoption by farmers in arid regions.
This
study
highlights
the
remarkable
adaptations and functional roles of microbial
communities in the Kyzylkum Desert, emphasizing their
critical contributions to ecosystem stability and
agricultural sustainability in arid environments.
Key Findings
1.
Diversity and Adaptations: Microbial
communities in the Kyzylkum Desert, including bacteria
(
Rhizobium
,
Bacillus
), fungi (
Aspergillus
,
Glomus
),
actinomycetes
(
Streptomyces
),
and
archaea
(
Halobacterium
), exhibit unique adaptations such as
exopolysaccharide
production,
osmoprotectant
synthesis, and antioxidative enzyme activity. These
traits enable them to survive and function in extreme
conditions, including salinity, drought, and nutrient-
poor soils.
2.
Ecological Roles:
o
These microbiomes play a vital role in
nutrient cycling, including nitrogen fixation and
phosphorus mobilization.
o
They enhance soil structure and
fertility through the production of exopolysaccharides
and secondary metabolites.
o
Microbial interactions with desert
plants improve water and nutrient uptake, making
them essential for vegetation cover and ecosystem
resilience.
3.
Agricultural Benefits: The functional
attributes of these microbes can be harnessed to
support sustainable agriculture by enhancing crop
productivity, reducing dependency on chemical
fertilizers, and mitigating abiotic stresses such as
salinity and drought.
Ecological and Agricultural Applications
1.
Bioinoculants for Arid Agriculture:
Developing bioinoculants based on stress-resilient
desert microbes can significantly enhance soil fertility
and crop growth in arid regions. For instance, nitrogen-
fixing bacteria and phosphate-solubilizing fungi can
address nutrient deficiencies in degraded soils.
2.
Combating Desertification: Utilizing
microbial consortia to restore degraded lands and
improve soil structure can mitigate desertification
processes. Exopolysaccharide-producing microbes are
particularly effective in stabilizing soils and preventing
erosion.
3.
Biocontrol Agents: The antimicrobial
properties of microbes such as
Streptomyces
and
Bacillus
spp. can be leveraged to develop eco-friendly
biocontrol agents, reducing the need for chemical
pesticides.
Practical Recommendations
1.
Promote Research and Development:
Further exploration of microbial diversity in the
Kyzylkum Desert is essential to uncover new species
and traits that can be applied in agriculture and
ecosystem restoration.
2.
Scale-Up Bioinoculant Production:
Invest in cost-effective methods for producing, storing,
and distributing bioinoculants, ensuring accessibility
for farmers in arid and semi-arid regions.
3.
Integrate Microbial Solutions into
Policy: Encourage the adoption of microbial
technologies in national strategies for combating
desertification and promoting sustainable agriculture.
The microbial communities of the Kyzylkum
Desert represent a valuable natural resource with
immense potential to address global challenges in
agriculture and environmental management. By
harnessing their ecological functions and adaptive
traits, we can develop innovative solutions to support
sustainable development in arid ecosystems.
REFERENCES
Vessey, J.K. Plant growth promoting rhizobacteria as
biofertilizers.
Plant and Soil
2003, 255, 571
–
586.
[CrossRef]
Bashan, Y.; Holguin, G.; de-Bashan, L.E. Azospirillum-
plant
relationships:
Physiological,
molecular,
agricultural, and environmental advances.
Can. J.
Microbiol.
2004, 50, 521
–
577. [CrossRef]
Khan, M.S.; Zaidi, A.; Wani, P.A. Role of phosphate-
solubilizing microorganisms in sustainable agriculture:
A review.
Agron. Sustain. Dev.
2010, 30, 31
–
44.
[CrossRef]
Mora-Ruiz, M.R.; Font-Verdera, F.; Pérez, J.A.; Mulet,
M. Bacterial diversity in soils.
Environ. Microbiol.
2016,
18, 3043
–
3055. [CrossRef]
Ruppel, S.; Franken, P.; Witzel, K. Properties and
applications of halotolerant microorganisms.
Plant and
Soil
2013, 364, 1
–
15. [CrossRef]
Oren, A. Thermodynamic limits to microbial life at high
salt concentrations.
Environ. Microbiol.
2011, 13,
1908
–
1923. [CrossRef]
Egamberdieva, D.; Wirth, S.J.; Behrendt, U.; Berg, G.
Antimicrobial activity of medicinal plants correlates
American Journal of Applied Science and Technology
53
https://theusajournals.com/index.php/ajast
American Journal of Applied Science and Technology (ISSN: 2771-2745)
with endophytic bacteria.
Plant and Soil
2015, 398,
217
–
227. [CrossRef]
Singh, B.K.; Bardgett, R.D.; Smith, P.; Reay, D.S.
Microorganisms and climate change.
Nat. Rev.
Microbiol.
2010, 8, 779
–
790. [CrossRef]
Sathya, A.; Vijayabharathi, R.; Gopalakrishnan, S.;
Srinivas, V. Actinomycetes: Plant growth-promoting
activities.
Springer Nat. Microbiol.
2017, 5, 103
–
115.
Gonzalez, C.F.; Marketon, M.M. Plant-microbe
interactions.
Mol. Plant-Microbe Interact.
2018, 31,
215
–
224. [CrossRef]
Hartmann, A.; Schmid, M.; van Tuinen, D.; Berg, G.
Plant-driven selection of microbes.
Plant and Soil
2014,
321, 235
–
257. [CrossRef]
Bashan, Y.; de-Bashan, L.E. Bacteria-plant relationships.
Springer-Verlag Microbiol. Ser.
2005, 8, 89
–
115.
Ma, Y.; Oliveira, R.S.; Freitas, H.; Zhang, C. Biochemical
mechanisms of plant-microbe-salt interactions.
Plant
and Soil
2019, 449, 1
–
22. [CrossRef]
Singh, J.S.; Gupta, V.K.; Kashyap, A.K. Desertification in
India.
Environ. Conserv.
2012, 39, 311
–
325. [CrossRef]
López, M.J.; Vargas-García, M.C.; Suárez-Estrella, F.;
Moreno, J. Compost microbial communities.
Springer
Int. Microbiol. Ser.
2016, 4, 205
–
218.
Zhang, J.; Wang, H.; He, M.; Chen, M.; Zhao, Z.
Microbial interactions with saline soil.
J. Microbiol.
2018, 56, 579
–
588. [CrossRef]
Friesen, M.L.; Porter, S.S.; Stark, S.C.; Von Wettberg,
E.J.; Sachs, J.L.; Martinez-Romero, E. Microbial
symbioses in agriculture: Diversity, benefits, and
challenges.
Nat. Rev. Microbiol.
2011, 9, 25
–
35.
[CrossRef]
Smith, S.E.; Read, D.J. Mycorrhizal Symbiosis; Academic
Press: London, UK, 2008; 800p.
Bever, J.D.; Platt, T.G.; Morton, E.R. Microbial dynamics
in the rhizosphere.
Annu. Rev. Microbiol.
2012, 66,
265
–
283. [CrossRef]
Zhu, Y.G.; Johnson, T.A.; Su, J.Q.; Qiao, M.; Guo, G.X.;
Stedtfeld, R.D.; Hashsham, S.A.; Tiedje, J.M. Diverse
and abundant antibiotic resistance genes in Chinese
swine farms.
Proc. Natl. Acad. Sci. USA
2013, 110,
3435
–
3440. [CrossRef]
Delgado-Baquerizo, M.; Maestre, F.T.; Gallardo, A.;
Bowker, M.A.; Wallenstein, M.D.; Quero, J.L.; Soliveres,
S.; Escolar, C.; García-Palacios, P.; Berdugo, M. Aridity
modulates N availability in arid ecosystems.
Ecology
2013, 94, 1407
–
1419. [CrossRef]
Berendsen, R.L.; Pieterse, C.M.J.; Bakker, P.A.H.M. The
rhizosphere microbiome and plant health.
Trends Plant
Sci.
2012, 17, 478
–
486. [CrossRef]
Schlaeppi, K.; Bulgarelli, D. The plant microbiome at
work.
Mol. Plant-Microbe Interact.
2015, 28, 212
–
217.
[CrossRef]
Walters, W.A.; Jin, Z.; Youngblut, N.; Wallace, J.G.;
Sutter, J.; Zhang, W.; Gonzalez-Pena, A.; Peiffer, J.;
Koren, O.; Shi, Q. Large-scale replicated field study of
maize rhizosphere identifies heritable microbes.
Proc.
Natl. Acad. Sci. USA
2018, 115, 7368
–
7373. [CrossRef]
Mendes, R.; Garbeva, P.; Raaijmakers, J.M. The
rhizosphere microbiome: Significance of plant
beneficial, plant pathogenic, and human pathogenic
microorganisms.
FEMS Microbiol. Rev.
2013, 37, 634
–
663. [CrossRef]
Bragina, A.; Berg, C.; Berg, G. The core microbiome
bonds the Alpine bog vegetation to a continuum of
plant-microbe interactions.
Microb. Ecol.
2015, 70,
428
–
440. [CrossRef]
Lugtenberg, B.J.J.; Caradus, J.R.; Johnson, L.J. Fungal
endophytes for sustainable crop production.
FEMS
Microbiol. Ecol.
2016, 92, 1
–
17. [CrossRef]
Hardoim, P.R.; van Overbeek, L.S.; van Elsas, J.D.
Properties of bacterial endophytes and their proposed
role in plant growth.
Trends Microbiol.
2008, 16, 463
–
471. [CrossRef]
Kuzyakov, Y.; Razavi, B.S. Rhizosphere size and shape:
Temporal dynamics and spatial stationarity.
Soil Biol.
Biochem.
2019, 135, 343
–
360. [CrossRef]
Philippot, L.; Raaijmakers, J.M.; Lemanceau, P.; van der
Putten, W.H. Going back to the roots: The microbial
ecology of the rhizosphere.
Nat. Rev. Microbiol.
2013,
11, 789
–
799. [CrossRef]
Richardson, A.E.; Simpson, R.J. Soil microorganisms
mediating phosphorus availability update on microbial
phosphorus.
Plant Physiol.
2011, 156, 989
–
996.
[CrossRef]
Verbon, E.H.; Liberman, L.M. Beneficial microbes: Plant
development and interspecies communication.
Curr.
Opin. Plant Biol.
2016, 34, 45
–
49. [CrossRef]
Lugtenberg, B.; Kamilova, F. Plant-growth-promoting
rhizobacteria.
Annu. Rev. Microbiol.
2009, 63, 541
–
556.
[CrossRef]
Fierer, N.; Jackson, R.B. The diversity and biogeography
of soil bacterial communities.
Proc. Natl. Acad. Sci. USA
2006, 103, 626
–
631. [CrossRef]
Bulgarelli, D.; Schlaeppi, K.; Spaepen, S.; van Themaat,
E.V.; Schulze-Lefert, P. Structure and functions of the
bacterial microbiota of plants.
Annu. Rev. Plant Biol.
2013, 64, 807
–
838. [CrossRef]
Chen, M.; Zhang, W.; Wu, X.; Guo, X.; He, X. Soil
microbial community and functional diversity in saline-
alkali land.
Appl. Soil Ecol.
2019, 135, 34
–
42. [CrossRef]
Guo, Q.; Han, J.; Li, Q.; Chen, Y.; Wang, Y. Advances in
phosphate solubilizing microorganisms for improving
phosphorus availability in soil.
J. Integr. Agric.
2020, 19,
367
–
378. [CrossRef]
Richardson, A.E.; Barea, J.M.; McNeill, A.M.; Prigent-
Combaret, C. Acquisition of phosphorus and nitrogen in
the rhizosphere and plant growth promotion by
microorganisms.
Plant Soil
2009, 321, 305
–
339.
[CrossRef]
American Journal of Applied Science and Technology
54
https://theusajournals.com/index.php/ajast
American Journal of Applied Science and Technology (ISSN: 2771-2745)
Mukherjee, A.; Singh, B.K.; Gour, J.P.; Adhya, T.K.
Rhizosphere microbial community in saline soils.
Curr.
Opin. Environ. Sustain.
2019, 39, 24
–
30. [CrossRef]
Jacoby, R.; Peukert, M.; Succurro, A.; Koprivova, A.;
Kopriva, S. The role of soil microorganisms in plant
mineral nutrition
—
Current knowledge and future
directions.
Front. Plant Sci.
2017, 8, 1617. [CrossRef]
Leff, J.W.; Lynch, R.C.; Kane, N.C.; Fierer, N. Plant
domestication and the assembly of bacterial and fungal
communities associated with crops.
New Phytol.
2017,
214, 412
–
423. [CrossRef]
Mendes, R.; Kruijt, M.; de Bruijn, I.; Dekkers, E.; van der
Voort, M.; Schneider, J.H.; Bakker, P.A. Deciphering the
rhizosphere microbiome for disease-suppressive
bacteria.
Science
2011, 332, 1097
–
1100. [CrossRef]
Bakker, P.A.; Pieterse, C.M.; de Jonge, R.; Berendsen,
R.L. The soil-borne legacy.
Cell
2018, 172, 1178
–
1180.
[CrossRef]
Cole, J.R.; Wang, Q.; Fish, J.A.; Chai, B.; McGarrell, D.M.;
Sun, Y.; Tiedje, J.M. Ribosomal Database Project: Data
and tools for high throughput rRNA analysis.
Nucleic
Acids Res.
2014, 42, D633
–
D642. [CrossRef]
Santi, C.; Bogusz, D.; Franche, C. Biological nitrogen
fixation in non-legume plants.
Ann. Bot.
2013, 111,
743
–
767. [CrossRef]
Diagne, N.; Arumugam, K.; Ngom, M.; Dramé, K.N.;
Djighaly, P.I.; Ndour, A.; Laplaze, L. Use of arbuscular
mycorrhizal fungi in agriculture.
Front. Plant Sci.
2020,
11, 1110. [CrossRef]
Yadav, R.; Singh, M.; Verma, J.P. Plant growth-
promoting microbial consortia for sustainable
agriculture.
Plant Soil Environ.
2020, 66, 1
–
13.
[CrossRef]
Peixoto, R.S.; Vermelho, A.B.; Rosado, A.S. Petroleum-
degrading enzymes: Bioremediation and new
prospects.
Enzyme Res.
2011, 2011, 475193. [CrossRef]
Bhattacharyya, P.N.; Jha, D.K. Plant growth-promoting
rhizobacteria (PGPR): Emergence in agriculture.
World
J. Microbiol. Biotechnol.
2012, 28, 1327
–
1350.
[CrossRef]
Parnell, J.J.; Berka, R.; Young, H.A.; Sturino, J.M.; Kang,
Y.; Barnhart, D.M.; DiLeo, M.V. From the lab to the
farm: An industrial perspective of plant beneficial
microorganisms.
Front. Plant Sci.
2016, 7, 1110.
[CrossRef]
Quiza, L.; St-Arnaud, M.; Yergeau, E. Harnessing
phytomicrobiome
signaling
for
rhizosphere
microbiome engineering.
Front. Plant Sci.
2015, 6, 507.
[CrossRef]
Van Oosten, M.J.; Pepe, O.; De Pascale, S.; Silletti, S.;
Maggio, A. The role of biostimulants and bioeffectors
as alleviators of abiotic stress in crop plants.
Chem. Biol.
Technol. Agric.
2017, 4, 5. [CrossRef]
Rey, T.; Dumas, B. Plenty is no plague: Pathogen-
associated molecular patterns (PAMPs) in plant
defense.
Trends Plant Sci.
2017, 22, 904
–
916.
[CrossRef]
Compant, S.; Clément, C.; Sessitsch, A. Plant growth-
promoting bacteria in the rhizo- and endosphere of
plants: Their role in plant health.
FEMS Microbiol. Ecol.
2010, 34, 613
–
629. [CrossRef]
Newton, A.C.; Gravouil, C.; Fountaine, J.M. Managing
the ecology of foliar pathogens: Ecological tolerance in
crops.
Ann. Appl. Biol.
2010, 157, 343
–
359. [CrossRef]
Dastogeer, K.M.; Tumpa, F.H.; Sultana, A.; Akter, M.A.;
Chakraborty, A. Plant microbiome
–
an account of the
factors that shape community composition and
diversity.
Curr. Plant Biol.
2020, 23, 100161. [CrossRef]
Yu, K.; Pieterse, C.M.; Bakker, P.A.; Berendsen, R.L.
Beneficial microbes going underground of root
immunity.
Plant Cell Environ.
2019, 42, 2860
–
2870.
[CrossRef]
Panke-Buisse, K.; Poole, A.C.; Goodrich, J.K.; Ley, R.E.;
Kao-Kniffin, J. Selection on soil microbiomes reveals
reproducible impacts on plant function.
ISME J.
2015,
9, 980
–
989. [CrossRef]
Winston, M.E.; Hampton-Marcell, J.; Zarraonaindia, I.;
Owens, S.M.; Moreau, C.S.; Gilbert, J.A.; Hartsel, J.
Understanding microbial community dynamics to
improve sustainable land management.
PLoS ONE
2014, 9, e105509. [CrossRef]
Trivedi, P.; Leach, J.E.; Tringe, S.G.; Sa, T.; Singh, B.K.
Plant
–
microbiome interactions: From community
assembly to plant health.
Nat. Rev. Microbiol.
2020, 18,
607
–
621. [CrossRef]
Callahan, B.J.; McMurdie, P.J.; Holmes, S.P. Exact
sequence variants should replace operational
taxonomic units in marker-gene data analysis.
ISME J.
2017, 11, 2639
–
2643. [CrossRef]
Adams, R.I.; Miletto, M.; Taylor, J.W.; Bruns, T.D. The
diversity and distribution of fungi on residential
surfaces.
PLoS ONE
2013, 8, e78866. [CrossRef]
Bulgarelli, D.; Garrido-Oter, R.; Munch, P.C.; Weiman,
A.; Dröge, J.; Pan, Y.; Schulze-Lefert, P. Structure and
function of the bacterial root microbiota in wild and
domesticated barley.
Cell Host Microbe
2015, 17, 392
–
403. [CrossRef]
Oyserman, B.O.; Medema, M.H.; Raaijmakers, J.M.
Roadmap to engineered bacterial plant microbiomes
for sustainable agriculture.
Trends Microbiol.
2018, 26,
952
–
963. [CrossRef]
Naylor, D.; DeGraaf, S.; Purdom, E.; Coleman-Derr, D.
Drought and host selection influence bacterial
community dynamics in the grass root microbiome.
ISME J.
2017, 11, 2691
–
2704. [CrossRef]
Edwards, J.; Johnson, C.; Santos-Medellín, C.; Lurie, E.;
Podishetty, N.K.; Bhatnagar, S.; Eisen, J.A. Structure,
variation, and assembly of the root-associated
microbiomes of rice.
Proc. Natl. Acad. Sci. USA
2015,
112, E911
–
E920. [CrossRef]
American Journal of Applied Science and Technology
55
https://theusajournals.com/index.php/ajast
American Journal of Applied Science and Technology (ISSN: 2771-2745)
Zhalnina, K.; Louie, K.B.; Hao, Z.; Mansoori, N.; da
Rocha, U.N.; Shi, S.; Brodie, E.L. Dynamic root exudate
chemistry and microbial substrate preferences drive
patterns in rhizosphere microbial community
assembly.
Nat. Microbiol.
2018, 3, 470
–
480. [CrossRef]
Fierer, N.; Breitbart, M.; Nulton, J.; Salamon, P.;
Lozupone, C.; Jones, R.; Rohwer, F. Metagenomic and
small-subunit rRNA analyses reveal the genetic
diversity of bacteria, archaea, fungi, and viruses in soil.
Appl. Environ. Microbiol.
2007, 73, 7059
–
7066.
[CrossRef]
Mendes, R.; Pizzirani-Kleiner, A.A.; Araujo, W.L.;
Raaijmakers, J.M. Diversity of cultivated endophytic
bacteria from sugarcane: Genetic and biochemical
characterization of Burkholderia cepacia complex
isolates.
Appl. Environ. Microbiol.
2007, 73, 7259
–
7267.
[CrossRef]
Vorholt, J.A. Microbial life in the phyllosphere.
Nat.
Rev. Microbiol.
2012, 10, 828
–
840. [CrossRef]
Bulgarelli, D.; Rott, M.; Schlaeppi, K.; Ver Loren van
Themaat, E.; Ahmadinejad, N.; Assenza, F.; Schulze-
Lefert, P. Revealing structure and assembly cues for
Arabidopsis root-inhabiting bacterial microbiota.
Nature
2012, 488, 91
–
95. [CrossRef]
Cheng, Z.; Park, E.; Glick, B.R. Role of plant growth-
promoting rhizobacteria in sustainable agriculture and
bioremediation.
Clim. Chang.
2007, 45, 273
–
291.
[CrossRef]
Schulz, B.; Boyle, C.; Draeger, S.; Römmert, A.K.; Krohn,
K. Endophytic fungi: A source of novel biologically
active secondary metabolites.
Mycol. Res.
2002, 106,
996
–
1004. [CrossRef]
Koskella, B.; Hall, L.J.; Metcalf, C.J.E. The microbiome
beyond the horizon of ecological and evolutionary
theory.
Nat. Ecol. Evol.
2017, 1, 1606
–
1615. [CrossRef]
Shade, A.; Jacques, M.A.; Barret, M. Ecological patterns
of seed microbiome diversity, transmission, and
assembly.
Curr. Opin. Microbiol.
2017, 37, 15
–
22.
[CrossRef]
Tkacz, A.; Cheema, J.; Chandra, G.; Grant, A.; Poole, P.S.
Stability and succession of the rhizosphere microbiota
depends upon plant type and soil composition.
ISME J.
2015, 9, 2349
–
2359. [CrossRef]
Hartman, K.; van der Heijden, M.G.A.; Roussely-
Provent, V.; Walser, J.-C.; Schlaeppi, K. Deciphering
composition and function of the root microbiome of a
legume plant.
Microbiome
2017, 5, 2. [CrossRef]
Martiny, J.B.; Bohannan, B.J.; Brown, J.H.; Colwell, R.K.;
Fuhrman, J.A.; Green, J.L.; Staley, J.T. Microbial
biogeography: Putting microorganisms on the map.
Nat. Rev. Microbiol.
2006, 4, 102
–
112. [CrossRef]
Van Der Heijden, M.G.; Bruin, S.; de Meijer, F.A.; Fry,
G.J. Arbuscular mycorrhizal fungi and Rhizobium
bacteria synergistically enhance nitrogen and
phosphorus acquisition of legumes.
Plant Soil
2003,
258, 151
–
159. [CrossRef]
Ramírez-Puebla,
S.T.;
Servín-Garcidueñas,
L.E.;
Jiménez-Marín, B.; Bolaños, L.M.; Rosenblueth, M.;
Martínez-Romero, E. The phyllosphere: Microbial
jungle at the plant
–
climate interface.
Front. Microbiol.
2020, 10, 2154. [CrossRef]
Niu, B.; Paulson, J.N.; Zheng, X.; Kolter, R. Simplified
and representative bacterial community of maize
roots.
Proc. Natl. Acad. Sci. USA
2017, 114, E2450
–
E2459. [CrossRef]
Hu, L.; Robert, C.A.; Cadot, S.; Zhang, X.; Ye, M.; Li, B.;
Rasmann, S. Root exudate metabolites drive plant-soil
feedbacks on growth and defense by shaping the
rhizosphere microbiota.
Nat. Commun.
2018, 9, 2738.
[CrossRef]
Levy, A.; Salas-González, I.; Mittelviefhaus, M.;
Clingenpeel, S.; Malfatti, S.; Tringe, S.G.; Dangl, J.L.
Genomic features of bacterial adaptation to plants.
Nat. Genet.
2018, 50, 138
–
150. [CrossRef]
Haichar, F.E.; Santaella, C.; Heulin, T.; Achouak, W. Root
exudates mediated interactions belowground.
Soil Biol.
Biochem.
2014, 77, 69
–
80. [CrossRef]
Badri, D.V.; Vivanco, J.M. Regulation and function of
root exudates.
Plant Cell Environ.
2009, 32, 666
–
681.
[CrossRef]
Gopal, M.; Gupta, A.; Pal, R.K. Applications of plant
growth-promoting microorganisms in the mitigation of
abiotic stress in plants.
Front. Plant Sci.
2020, 11, 2016.
[CrossRef]
Zamioudis, C.; Pieterse, C.M.J. Modulation of host
immunity by beneficial microbes.
Mol. Plant-Microbe
Interact.
2012, 25, 139
–
150. [CrossRef]
Mendes, R.; Raaijmakers, J.M. Impact of bacterial and
fungal volatiles on plant health.
Trends Plant Sci.
2015,
20, 206
–
211. [CrossRef]
Hacquard, S.; Garrido-Oter, R.; González, A.; Spaepen,
S.; Ackermann, G.; Lebeis, S.L.; Schulze-Lefert, P.
Microbial community composition and functional
diversity in the phyllosphere and rhizosphere of
Arabidopsis thaliana.
Nat. Commun.
2015, 6, 4323.
[CrossRef]
Peiffer, J.A.; Spor, A.; Koren, O.; Jin, Z.; Tringe, S.G.;
Dangl, J.L.; Ley, R.E. Diversity and heritability of the
maize rhizosphere microbiome under field conditions.
Proc. Natl. Acad. Sci. USA
2013, 110, 6548
–
6553.
[CrossRef]
Vandenkoornhuyse, P.; Quaiser, A.; Duhamel, M.; Le
Van, A.; Dufresne, A. The importance of the
microbiome of the plant holobiont.
New Phytol.
2015,
206, 1196
–
1206. [CrossRef]
Berg, G.; Smalla, K. Plant species and soil type
cooperatively shape the structure and function of
microbial communities in the rhizosphere.
FEMS
Microbiol. Ecol.
2009, 68, 1
–
13. [CrossRef]
American Journal of Applied Science and Technology
56
https://theusajournals.com/index.php/ajast
American Journal of Applied Science and Technology (ISSN: 2771-2745)
Deveau, A.; Bonito, G.; Uehling, J.; Paoletti, M.; Becker,
M.; Bindschedler, S.; Martin, F. Bacterial-fungal
interactions: Ecology, mechanisms, and challenges.
Fungal Biol. Rev.
2018, 32, 62
–
77. [CrossRef]
Pérez-Jaramillo, J.E.; Carrión, V.J.; de Hollander, M.;
Raaijmakers, J.M. The wild side of plant microbiomes.
Microbiome
2018, 6, 143. [CrossRef]
Haichar, F.E.; Achouak, W.; Christen, R.; Heulin, T.;
Marol, C.; Marais, M.F.; Berge, O. Stable isotope
probing analysis of the diversity and activity of
methanol-utilizing bacteria in the rhizosphere.
ISME J.
2007, 1, 464
–
478. [CrossRef]
Pii, Y.; Mimmo, T.; Tomasi, N.; Terzano, R.; Cesco, S.;
Crecchio, C. Microbial interactions in the rhizosphere:
Beneficial influences of plant growth-promoting
rhizobacteria on nutrient acquisition process.
A Review.
Biology and Fertility of Soils
2015, 51, 403
–
415.
[CrossRef]
Glick, B.R.; Penrose, D.M.; Li, J. A model for the
lowering of plant ethylene concentrations by plant
growth-promoting bacteria.
J. Theor. Biol.
1998, 190,
63
–
68. [CrossRef]
Vessey, J.K. Plant growth promoting rhizobacteria as
biofertilizers.
Plant and Soil
2003, 255, 571
–
586.
[CrossRef]
Compant, S.; Duffy, B.; Nowak, J.; Clément, C.; Barka,
E.A. Use of plant growth-promoting bacteria for
biocontrol of plant diseases: Principles, mechanisms of
action, and future prospects.
Appl. Environ. Microbiol.
2005, 71, 4951
–
4959. [CrossRef]
Lugtenberg, B.J.J.; Kamilova, F. Plant-growth-
promoting rhizobacteria.
Annu. Rev. Microbiol.
2009,
63, 541
–
556. [CrossRef]
Kumar, A.; Singh, R.; Yadav, A.; Giri, D.D.; Singh, P.K.;
Pandey, K.D. Isolation and characterization of bacterial
endophytes of Curcuma longa L. 3 Biotech 2016, 6, 60.
[CrossRef]
Santoyo, G.; Moreno-Hagelsieb, G.; Orozco-Mosqueda,
M.D.C.; Glick, B.R. Plant growth-promoting bacterial
endophytes.
Microbiol. Res.
2016, 183, 92
–
99.
[CrossRef]
Redman, R.S.; Sheehan, K.B.; Stout, R.G.; Rodriguez,
R.J.; Henson, J.M. Thermotolerance generated by
plant/fungal symbiosis.
Science
2002, 298, 1581.
[CrossRef]
Zahir, Z.A.; Arshad, M.; Frankenberger, W.T. Plant
growth promoting rhizobacteria: Applications and
perspectives in agriculture.
Adv. Agron.
2004, 81, 97
–
168. [CrossRef]
Mishra, J.; Arora, N.K. Secondary metabolites of
fluorescent
pseudomonads
in
biocontrol
of
phytopathogens for sustainable agriculture.
Appl. Soil
Ecol.
2018, 125, 35
–
45. [CrossRef]
Rajkumar, M.; Ae, N.; Freitas, H. Endophytic bacteria
and their potential to enhance heavy metal
phytoextraction.
Chemosphere
2009, 77, 153
–
160.
[CrossRef]
Barea, J.M.; Pozo, M.J.; Azcón, R.; Azcón-Aguilar, C.
Microbial co-operation in the rhizosphere.
J. Exp. Bot.
2005, 56, 1761
–
1778. [CrossRef]
Boller, T.; Felix, G. A renaissance of elicitors: Perception
of microbe-associated molecular patterns and danger
signals by pattern-recognition receptors.
Annu. Rev.
Plant Biol.
2009, 60, 379
–
406. [CrossRef]
Dobbelaere, S.; Croonenborghs, A.; Thys, A.; Ptacek, D.;
Vanderleyden, J.; Dutto, P.; Okon, Y. Responses of
agronomically important crops to inoculation with
Azospirillum.
A Review. Eur. J. Agron.
2001, 15, 145
–
170. [CrossRef]
Pieterse, C.M.J.; Zamioudis, C.; Berendsen, R.L.; Weller,
D.M.; van Wees, S.C.M.; Bakker, P.A.H.M. Induced
systemic resistance by beneficial microbes.
Annu. Rev.
Phytopathol.
2014, 52, 347
–
375. [CrossRef]
