A Low-Cost Approach to Evaluation of Forage Breeding Lines Under Grazing and Its Application to Limpograss Cultivar Development.

Limpograss [Hemarthria altissima (Poir.) Stapf et C. E. Hubb.] is a stoloniferous, warm-season perennial grass which use has increased from zero to perhaps as much as 200,000 ha in Florida in the past 30 years. It’s cold tolerance, extended growing season, high digestibility and persistence in poorly drained soil makes it suitable to the state conditions a promising forage to be even more explored (Quesenberry et al., 2004). Recently, Quesenberry and his colleagues undertook the task of developing new limpograss cultivars by crossing the highly digestible Bigalta with the more persistent Floralta. The goal was to achieve superior cultivars with both high digestibility and persistence. Fifty lines where generated and tested under clipping. Eight selected lines and the two parents were tested in an experiment that was established at the University of Florida Beef Research Unit near Gainesville in July 2009 and mob grazed during the growing seasons of 2010 and 2011. The lines were submitted to two grazing frequency treatments (2 and 4 weeks) to access herbage mass production, weed frequency, limpograss cover, in vitro organic matter digestibility and crude protein. Two of the lines had inferior results and poor persistence. The remaining five are going to be tested in a further experiment.