Conventional farming techniques help in fulfilling food demand but they are harmful to humans and environmental sustainability. These largely depend on chemical fertilizers that cause food contamination and soil toxicity and deteriorate the physical, chemical, and biological properties of soil. Minerals are essential macro and micronutrients that play a vital role in plant growth and development. However, the solubility of minerals is very low and unavailable to plants. Plant growth-promoting (PGP) microorganisms are a group of beneficial soil microorganisms that could be rhizospheric, endophytic, and phyllospheric or inhabit extreme habitats, and majorly belongs to bacteria, fungi, and actinomycetes. PGP microorganisms play a dynamic role in the accessibility of various minerals, especially nitrogen (N), phosphorus (P), potassium (K), zinc (Zn), silicon (Si), and iron (Fe). Mineral solubilizing microorganisms (MSMs) increase the mineral concentration by mineral solubility in soil and its availability to plants. MSMs showed their ability to convert the insoluble form of minerals to soluble forms through different mechanisms such as acidification, exchange reactions, chelation, production of acid phosphatases and phytases, phytohormone production, and siderophore. This promotes the uptake of minerals in plants, thereby relieving the plants from abiotic stress (salinity, drought, flooding, and extreme temperature) and increasing productivity. Biofertilizers developed using MSMs could be an eco-friendly solution to the sustainable food production system worldwide. However, it's important to note that the effectiveness of mineral-solubilizing microorganisms can vary depending on environmental factors, soil conditions, and specific crop requirements. Therefore, it is recommended to conduct site-specific research and consult with agricultural experts to determine the most appropriate microbial strains and application methods for a given farming system. A limited number of studies reported where a single microorganism solubilizes several minerals and utilize them as biofertilizers. Currently, we are working on identifying the multi-mineral solubilizing microorganism from rhizosphere of different crops and medicinal plants, and their potential roles in crop improvement and agricultural sustainability.
Audience Take Away Notes :
- Mineral solubilizing microorganisms have the potential to be employed as biocontrol agents or biofertilizers in agricultural crops, to improve crop yields and the plant’s tolerance to biotic and abiotic stress.
- Rhizospheric, endophytic, and phyllospheric microorganisms could be a possible source of secondary metabolites or hormones for sustainable agriculture.
- Further characterization of multi-mineral solubilizing microorganisms will provide a great achievement in the production of biofertilizers to manage biotic and abiotic stress in plants.
- The use of multi-mineral solubilizing microorganisms as biofertilizers not only increases crop productivity but also improves the socio-economic status of farmers in low and middle-income countries.