|MadSci Network: Microbiology|
Microbes (fungi and bacteria) are critical to the growth of plants in the soil. Many plants rely on a symbiotic relationship with a type of fungi called mycorrhizae. These fungi grow in and on plant roots and send little fungal shoots, called hyphae, out into the soil to collect crucial nutrients like phosphorus and calcium, which are then transferred to the plant. Other microbes (decomposers) break down organic matter in the soil. This releases the nutrients into the soil which plants can then take up. Without decomposers, dead organic matter would just pile up and plants would be starved for nutrients like nitrogen and phosphorus.
If you plant a tree which relies on mycorrhizae in sterilized soil, it will still grow but it will be much smaller and less healthy than the ones grown with mycorrhizae. In the long run, plants rely on microbes to break down organic matter in the soil (allowing nutrients to be recycled) and no ecosystem could continue to function without them.
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