**4. Mycorrhizal fungi and other soil organisms**

Mycorrhizal fungi interrelate with a vast variety of other soil microorganisms. This interaction may occur in the rhizosphere or in the loose soil. All these interactions may act as an inhibitor or may play a role as a stimulator; most of the time, they play a role of a symbiotic or a competitor. Effects can be observed evidently at all the phases of the life cycle of MF from the spore population dynamic role of mycorrhizal helper bacteria (MHB) in symbiosis interaction; it is very important for bacteria and grazing animals to maintain and sustain this interaction or symbiotic relationship. Mycorrhizal fungi are also capable to amend the associations of plants with other soil organisms—both pathogens, for example, root-inhabiting nematode, fungi, and particularly nitrogen-fixing bacteria. These connections may be significant in natural environment where microbes play regulatory roles, and in agricultural systems, mycorrhizas may be important in the formation of integrated systems of pest control and growth stimulation [10].
