Food security is a fundamental need of all societies. The world population is projected to reach 9.2 billion by 2050, which means that agricultural production must increase by 60-70% over current levels to keep pace with the growing demand for food (Gao et al., 2022). Therefore, global agricultural production will face several challenges, including dealing with biotic and abiotic stresses. Biotic stress includes damage caused by various pests and microbial pathogens, while abiotic stress includes drought, both high and low temperatures, flooding, heavy metals contamination, and salinity, to mention but a few (Glick, 2020; Jiménez-Mejía et al., 2022). In the case of soil salinity, this is of major relevance in agricultural production. Worldwide, about 20% of agricultural land is affected by salinity; it is estimated that by 2050, this will increase to around 50% (Mukhopadhyay et al., 2021). Soil salinization is produced by the accumulation of soluble salts such as NaCl, Mg, NO3, HCO3−, SO4−; however, NaCl contributes most of the salts to saline soils (Gupta et al., 2022a). Conventionally, the electrical conductivity (EC) of the saturated extract has been used as a measure of soil salinity (Hassani et al., 2021). A soil with an EC greater than or equal to 4 deciSiemens per meter (dS m−1) at 25 °C and pH <8.5, is considered saline, which is approximately equivalent to 40 mM NaCl (Mohanavelu et al., 2021). It should be noted that although these salinity values may be tolerant for a large part of bacteria such as the Bacillus genus, as well as other groups naturally tolerant to salinity, agricultural crops may have problems adapting to these conditions and have productivity problems.

Salinity is also a natural component of the ecosystems in arid and semi-arid regions (due to low rainfall and high temperatures), coastal regions, and in rock and mineral deposits; although anthropogenic activities such as poor agricultural practices also promote soil salinization through irrigation with saline water, deficient soil management and the excessive use of chemical fertilizers, pesticides and fungicides, which ultimately reduces fertility, quality soil and makes crops vulnerable to infection by pathogens (Etesami and Beattie, 2018; Etesami and Glick, 2020; Lopez-Alvarez et al., 2021).

Globally, the regions most affected by salinity include the Asia Pacific and Australia. These two parts of the world cover a total agricultural area of 2016 million hectares (ha), of which 27% is affected by salinity. In Africa, 72.2 million ha of land is affected by salinity, which represents approximately 6.40% of the total agricultural area. The American continent has a total of 1223 million hectares of total agricultural area, of which 130.5 million hectares of land are saline. In Europe, 17.30% of the earth's agricultural land faces the problem of salinity (Kumar et al., 2020). These numbers give us an idea of the global impact of the problem of soil salinity, affecting much of the global arable land.

Salinity has drastic consequences for plants, which is explored in more detail below (Majeed and Muhammad, 2019). Therefore, it is important to seek and apply remedies to achieve sustainable agriculture such as the use of beneficial microorganisms, including plant growth-promoting bacteria (PGPB) of the genus Bacillus, which are excellent bioprotectants and/or biostimulants of plant growth under saline stressful conditions (Hernández-Canseco et al., 2022).