The approach of using reinfection with naturally occurring novel strains into commercially viable cultivars should continue in the near future (Bouton, 2007b). The basis of this strategy is to keep the main agronomic traits of the current cultivar intact and to add the value of the endophyte without toxic side effects (Bouton and Easton, 2005). This approach relies on the best strain-cultivar combination being successful. However, not all infections done at the cultivar level have been successful from an agronomic point of view (Bouton et al., 2002). The higher price of MaxQ vs. conventional tall fescue seed, two- to threefold higher, also demands that a successful endophyte-cultivar combination be delivered to the farmer.
Maintaining endophyte viability during the breeding and development, seed production, marketing, and on-farm establishment phases is an important problem because endophytes die in the seed faster than the embryo itself (Bouton and Hopkins, 2003; Bouton and Easton, 2005; Rolston and Agee, 2007). Quality control approaches are necessary for all of these phases if a company is to ensure high viability and infection rates.
Assays to determine endophyte presence and alkaloid concentration are critical to any quality assurance program for novel endophyte commercialization (Bouton and Easton, 2005; Rolston and Agee, 2007). These assessment systems are regularly refined, allowing efficient handling of large sample sets. Development of immunoblot procedures for detecting endophyte presence (Hiatt et al., 1997) and enzyme linked immunosorbent assay (ELISA) methods for assessment of ergot alkaloids (Adcock et al., 1997) were important during development and evaluation of MaxQ. Use of detection techniques based on molecular markers, such as simple sequence repeats (SSRs) (see Chapter 21), owing to their specificity, now have the potential for assessing strain identification (Rolston and Agee, 2007).