Fungal endophytes of Festuca rubra increase in frequency following long-term exclusion of rabbits

Plants have lived in close association with fungal symbionts for most of their evolutionary history on land. Some fungi are so tightly associated with plants that they only occur inside plant tissues (endophytes), being passed between generations via seeds. Do these fungi have any functional significance to the plants? Undergraduate student James Santangelo and former PhD student Dr. Nash Turley (Johnson Lab) recently addressed this question in “Fungal endophytes of Festuca rubra increase in frequency following long-term exclusion of rabbits” published in Botany. They tested the hypothesis that fungal endophytes help defend a native grass against herbivores, like rabbits. To their surprise, fungal endophytes were more common in plants in the presence of rabbits and least common in plant populations that had been protected from rabbits for up 21 years. Subsequent experiments showed that the endophytes directly benefit plant growth, possibly giving plants a competitive advantage when they aren’t bunny chow. James and Nash’s work show that fungal endophytes play diverse mutualistic roles with their plant hosts. Congratulations!