Plants and mycorrhizae (fungi that grow in association with plant roots) are usually mutualistic.The fungus absorbs water and minerals, such as phosphorus, from the soil, which the plant uses.The plant provides the fungus with carbohydrates.In soils where phosphorus is low, nutrient transfer from fungus to plant may increase plant fitness.But in very fertile soils, the net benefit of the interaction may become negative, with the fungus acting more as a parasite than a mutualist.Which is the best description of the change in this interaction?

Question

Quizplus · Accepted Answer

The description of the change suggests that the interaction moves along a continuum in response to changes in the environment. Initially, in low-phosphorus soils, the interaction is mutualistic, with the fungus providing necessary nutrients to the plant in exchange for carbohydrates. However, in very fertile soils, the net benefit of the interaction may become negative, with the fungus acting more as a parasite than a mutualist, suggesting a shift towards a more parasitic relationship. This change is not a fixed evolutionary change but rather a dynamic response to environmental conditions.

Plants and Mycorrhizae (Fungi That Grow in Association with Plant