sentences:  Recently it has been shown that "Epichloë uncinata" infection and loline content afford "× Festulolium" grasses protection from black beetle (Heteronychus arator).Many species in "Epichloë" produce biologically active alkaloids, such as ergot alkaloids, indole-diterpenoids (e.g., lolitrem B), loline alkaloids, and the unusual guanidinium alkaloid, peramine.It has been proposed that vertically transmitted symbionts should evolve to be mutualists since their reproductive fitness is intimately tied to that of their hosts.