Chapter 9
Phosphate Solubilization by Endophytes
from the Tropical Plants
Paulo Teixeira Lacava, Paula Cristiane Machado,
and Paulo Henrique Marques de Andrade
Abstract Currently, agriculture depends heavily on a variety of agrochemicals,
such as mineral fertilizers and pesticides, that often have adverse effects on human
health and environmental ecosystems. Furthermore, the indiscriminate application
of pesticides has severe effects on soil ecology that may lead to alterations in plant
and soil microbiomes. Modern agricultural biotechnology has shown that microbial inoculants can be used to enhance plant growth and can thereby reduce the use
of agrochemicals. In this context, the utilization of endophytic microorganisms for
agricultural purposes has increased recently, especially their use for plant growth
promotion. Endophytes are microorganisms that live in plant tissues without causing
apparent disease in the host plant. Endophytic microorganisms promote plant growth
in three major ways: they synthesize particular compounds that are useful for the
plants, they facilitate the uptake of certain nutrients from the soil, and they control
or prevent diseases. Growth promotion mediated by endophytes occurs via several
mechanisms: the production of vital enzymes; the production of hormones such
as auxin (indoleacetic acid [IAA]); the symbiotic fixation of nitrogen; the production of siderophores, chitinases, or antibiotics for protection from phytopathogens;
and the solubilization and mineralization of nutrients, particularly insoluble mineral
phosphates. Endophytic microorganisms can be used to improve nutrient utilization because they solubilize phosphate, making it available for absorption by plants.
Among these microorganisms are phosphate-solubilizing bacteria and fungi that
P. T. Lacava (B) · P. H. M. de Andrade
Laboratory of Microbiology and Biomolecules – LaMiB, Department of Morphology and
Pathology, Center for Biological and Health Sciences, Federal University of São Carlos, Via
Washington Luís km 235, PO BOX 676, São Carlos, SP 13565-905, Brazil
e-mail: ptlacava@ufscar.br
P. T. Lacava · P. C. Machado
Biotechnology Graduation Program – PPGBiotec, Center of Exact Sciences and Technology,
Federal University of São Carlos, Via Washington Luís km 235, São Carlos, SP 13565-905, Brazil
P. T. Lacava · P. H. M. de Andrade
Evolutionary Genetics and Molecular Biology Graduation Program – PPGGEv, Center for
Biological and Health Sciences, Federal University of São Carlos, Via Washington Luís km 235,
São Carlos, SP 13565-905, Brazil
© 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_9
207
Phosphate Solubilization by Endophytes
from the Tropical Plants
Paulo Teixeira Lacava, Paula Cristiane Machado,
and Paulo Henrique Marques de Andrade
Abstract Currently, agriculture depends heavily on a variety of agrochemicals,
such as mineral fertilizers and pesticides, that often have adverse effects on human
health and environmental ecosystems. Furthermore, the indiscriminate application
of pesticides has severe effects on soil ecology that may lead to alterations in plant
and soil microbiomes. Modern agricultural biotechnology has shown that microbial inoculants can be used to enhance plant growth and can thereby reduce the use
of agrochemicals. In this context, the utilization of endophytic microorganisms for
agricultural purposes has increased recently, especially their use for plant growth
promotion. Endophytes are microorganisms that live in plant tissues without causing
apparent disease in the host plant. Endophytic microorganisms promote plant growth
in three major ways: they synthesize particular compounds that are useful for the
plants, they facilitate the uptake of certain nutrients from the soil, and they control
or prevent diseases. Growth promotion mediated by endophytes occurs via several
mechanisms: the production of vital enzymes; the production of hormones such
as auxin (indoleacetic acid [IAA]); the symbiotic fixation of nitrogen; the production of siderophores, chitinases, or antibiotics for protection from phytopathogens;
and the solubilization and mineralization of nutrients, particularly insoluble mineral
phosphates. Endophytic microorganisms can be used to improve nutrient utilization because they solubilize phosphate, making it available for absorption by plants.
Among these microorganisms are phosphate-solubilizing bacteria and fungi that
P. T. Lacava (B) · P. H. M. de Andrade
Laboratory of Microbiology and Biomolecules – LaMiB, Department of Morphology and
Pathology, Center for Biological and Health Sciences, Federal University of São Carlos, Via
Washington Luís km 235, PO BOX 676, São Carlos, SP 13565-905, Brazil
e-mail: ptlacava@ufscar.br
P. T. Lacava · P. C. Machado
Biotechnology Graduation Program – PPGBiotec, Center of Exact Sciences and Technology,
Federal University of São Carlos, Via Washington Luís km 235, São Carlos, SP 13565-905, Brazil
P. T. Lacava · P. H. M. de Andrade
Evolutionary Genetics and Molecular Biology Graduation Program – PPGGEv, Center for
Biological and Health Sciences, Federal University of São Carlos, Via Washington Luís km 235,
São Carlos, SP 13565-905, Brazil
© 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_9
207