Resource-resource relationships Mutualistic relationships can be thought of as a form of "biological barter" in mycorrhizal associations between plant roots and fungi, with the plant providing carbohydrates to the fungus in return for primarily phosphate but also nitrogenous compounds. Other examples include rhizobia bacteria that fix nitrogen for leguminous plants (family Fabaceae) in return for energy-containing carbohydrates. Metabolite exchange between multiple mutualistic species of bacteria has also been observed in a process known as cross-feeding.
Resource-resource relationships Mutualistic relationships can be thought of as a form of "biological barter" in mycorrhizal associations between plant roots and fungi with the plant providing carbohydrates to the fungus in return for primarily phosphate but also nitrogenous compounds Other examples include rhizobia bacteria that fix nitrogen for leguminous plants (family Fabaceae) in return for energy-containing carbohydrates Metabolite exchange between multiple mutualistic species of bacteria has also been observed in a process known as cross-feeding