A variety of organic compounds released from roots provide a source of energy and carbon for soil organisms. Roots provide an important habitat for bacteria, fungi and very small soil animals. The number of organisms can be about 500 times more in the rhizosphere than in the bulk soil matrix.  

Inoculation of field soils with microorganisms is practiced either to introduce specific organisms (such as rhizobia, mycorrhizal fungi or Bacillus subtilis as biological control organisms) or to enhance the overall biological activity in the soil with microbial mixtures.

Nutrient deficiency is an indication that the plant may benefit from the introduction of rhizobia (nitrogen deficiency) or mycorrhizal fungi (phosphorus deficiency). The value of mixed microbial inoculants needs to be based on their capacity to enhance overall microbial activity, stimulate nutrient cycling, increase disease resistance and/or improve physical soil conditions mediated by biological processes.

AN OUNCE OF

While plants have a natural defense system (SAR ) to fight off stress from disease and adverse conditions, their defense system is not activated until the plant actually comes under stress from disease or environmental stress. In other words, the plant’s ability to fight off disease and stress is delayed until the attack strikes, catching the plant in a low state of readiness to ward off the effect and minimize yield loss.