Explanation:

Mycorrhiza is the association of the fungus with the root of the vascular host plant. It increases the water and nutrition absorption capacity of the plant. Rhodospirillum - mycorrhiza ( the association of the fungus with the root of the vascular host plant). It increases the water and nutrition absorption capacity of the plant. Rhodospirillum is a facultative anaerobe. It is a nitrogen fixer which helps in the conversion of atmospheric nitrogen to ammonia. It is not associated with roots of the vascular plant as mycorrhiza.