Chapter 3
Microbial Endophytes: Sustainable
Approach for Managing Phosphorus
Deficiency in Agricultural Soils
Anupma Dahiya, Rakesh Kumar, and Satyavir S. Sindhu
Abstract Phosphorus (P) is the second most essential mineral nutrient after nitrogen
for plant growth and development. The available form of P for plants is generally
low even in fertile soils throughout the world. Phosphorus deficiency in soil is traditionally overcome by adding the phosphatic fertilizers, which also gets fixed into
insoluble unavailable forms due to the high reactivity of soluble P with calcium,
iron, or aluminum. The repeatedly applied fertilizer to agricultural fields led to the
loss of soil fertility disturbs the soil microbial flora and causes pollution problems.
Phosphate solubilizing microbial endophytes have played a significant role in phosphate solubilization. Endophytic microorganisms associated with different parts of
the plants release organic acids into the soil, which solubilize the bound form of
phosphate complexes and converts them into ortho-phosphate for uptake and utilization by plants. Inoculation of endophytic phosphate solubilizing microorganisms is
a reliable technique for increasing soluble P in the soil leading to improved plant
biomass and yield of crops. The rhizospheric bioengineering of bacterial strains to
enhance phosphate solubilizing capacity will further help in improving the efficacy
of biofertilizer inoculants for increasing crop productivity in sustainable agriculture.
Thus, the use of plant growth-promoting bacterial endophytes as microbial biofertilizers provides a promising eco-friendly and cost-effective alternative to chemical
fertilizers in sustainable agriculture.
Keywords Endophytes · Plant colonization · Phosphate solubilization · Plant
growth promotion · Biofertilizers
3.1 Introduction
In the endophytic growth, microorganisms invade and develop close mutualistic relationships with the plants. They live in cells and tissues, and establish their interaction
with different degrees of dependence, surface-sterilized plant tissues. They do not
A. Dahiya · R. Kumar · S. S. Sindhu (B)
Department of Microbiology, CCS Haryana Agricultural University, Hisar 125 004, India
e-mail: sindhuss@hau.ac.in
© Springer Nature Switzerland AG 2021
D. K. Maheshwari and S. Dheeman (eds.), Endophytes: Mineral Nutrient
Management, Volume 3, Sustainable Development and Biodiversity 26,
https://doi.org/10.1007/978-3-030-65447-4_3
35
Microbial Endophytes: Sustainable
Approach for Managing Phosphorus
Deficiency in Agricultural Soils
Anupma Dahiya, Rakesh Kumar, and Satyavir S. Sindhu
Abstract Phosphorus (P) is the second most essential mineral nutrient after nitrogen
for plant growth and development. The available form of P for plants is generally
low even in fertile soils throughout the world. Phosphorus deficiency in soil is traditionally overcome by adding the phosphatic fertilizers, which also gets fixed into
insoluble unavailable forms due to the high reactivity of soluble P with calcium,
iron, or aluminum. The repeatedly applied fertilizer to agricultural fields led to the
loss of soil fertility disturbs the soil microbial flora and causes pollution problems.
Phosphate solubilizing microbial endophytes have played a significant role in phosphate solubilization. Endophytic microorganisms associated with different parts of
the plants release organic acids into the soil, which solubilize the bound form of
phosphate complexes and converts them into ortho-phosphate for uptake and utilization by plants. Inoculation of endophytic phosphate solubilizing microorganisms is
a reliable technique for increasing soluble P in the soil leading to improved plant
biomass and yield of crops. The rhizospheric bioengineering of bacterial strains to
enhance phosphate solubilizing capacity will further help in improving the efficacy
of biofertilizer inoculants for increasing crop productivity in sustainable agriculture.
Thus, the use of plant growth-promoting bacterial endophytes as microbial biofertilizers provides a promising eco-friendly and cost-effective alternative to chemical
fertilizers in sustainable agriculture.
Keywords Endophytes · Plant colonization · Phosphate solubilization · Plant
growth promotion · Biofertilizers
3.1 Introduction
In the endophytic growth, microorganisms invade and develop close mutualistic relationships with the plants. They live in cells and tissues, and establish their interaction
with different degrees of dependence, surface-sterilized plant tissues. They do not
A. Dahiya · R. Kumar · S. S. Sindhu (B)
Department of Microbiology, CCS Haryana Agricultural University, Hisar 125 004, India
e-mail: sindhuss@hau.ac.in
© Springer Nature Switzerland AG 2021
D. K. Maheshwari and S. Dheeman (eds.), Endophytes: Mineral Nutrient
Management, Volume 3, Sustainable Development and Biodiversity 26,
https://doi.org/10.1007/978-3-030-65447-4_3
35