They do this by extracting the nutrients from the soil, but then rather than trading them with the host, they hoard them in their network, so this makes them unavailable to the plant and other competing fungi.
Eles fazem isso extraindo os nutrientes do solo, mas, aí, em vez de negociá-los com a hospedeira, eles os estocam em sua rede, tornando-os indisponíveis  para a planta e fungos concorrentes.