Old dog, new trick: The PHR-SPX system regulates arbuscular mycorrhizal symbiosis

Abstract

Plant growth depends on the continuous availability of the macronutrient phosphate (Pi). However, in most soils, Pi is only poorly accessible to plants, resulting in Pi deficiency and triggering a number of Pi starvation responses. One strategy of plants to overcome Pi limitation is to form a symbiosis with arbuscular mycorrhizal (AM) fungi (Smith et al., 2011), which occurs with approximately 80% of land plants. AM fungi improve the uptake of Pi and other mineral nutrients and thereby increase plant performance and stress tolerance.