What is mutualism? Mention any two examples where the organisms involved are commercially exploited in modern agriculture.

Explanation

Mutualism is an interaction between two species of organisms in which both are benefitted from the obligate association. Common examples where the interaction is commercially exploited in modern agriculture are :
(i) The cyanobacterium Anabaena is found in the leaves of the water fern Azolla It is used as bio-fertilizer for wet land rice cultivation, since Anabaena fixes atmospheric nitrogen and lives in mutualistic association with Azolla. The soil is thus rich in nitrogen.
(ii) Mycorrihiza are formed by symbiotic association of certain fungal hyphae with roots of Angiosperms. They increase the availability of phosphorous in the soil and 'i also assures water availability.