STAGE 4: The Environment

Most microbial products commercially available in the United States have been developed for a mass market, and no microbial inoculant has proved to be effective in all environments. 

Through research, the survival and persistence of microbes in the soil, has been shown to be affected by extreme soil pH, desiccation, nutrient deficiencies, salinity/alkalinity, extreme temperatures, and toxicities. 

In general, microbial inoculant survival and concentration are favored by neutral pH, adequate moisture, adequate organic carbon, and low salinity. Resource availability and the extent of native species diversity and concentration in the soil also impacts microbe survival.  

The concept of the ‘disease triangle’ can be similarly applied to beneficial microbes in which the plant host, beneficial microbe, and environment must all interact positively to achieve the desired outcomes in plant growth promotion and performance.

For a more detailed discussion of The System, The Environment, and Delivery, see our FULL article Fixing our perspective on N-fixing.