ABSTRACT
Natalie Christian, Briana K. Whitaker, and Keith Clay
5.1 INTRODUCTION
Endophytic fungi are internal colonizers of aboveground tissues in all plant species studied to date (U’Ren et al. 2012). These cryptic organisms engage in a diverse set of symbioses and biological interactions with their plants hosts, from local infections of leaf tissues (Rodriguez et al. 2009) and bark (de Errasti, Carmarán, and Victoria Novas 2010) in herbaceous and woody plants to the systemic infections famously found in cool-season grasses (Clay and Schardl 2002). Moreover, endophytes range from mutualists to pathogens and saprobes, with great variation in the direction, the magnitude, and the frequency of ›tness consequences for the host, as well as in their method of transmission from one host to the next through space and time (Clay and Schardl 2002; Porras-Alfaro and Bayman 2011).
