Establishment, yield, and competitiveness of rhizoma perennial peanut germplasm on a flatwoods soil

Rhizoma perennial peanut (RPP) (Arachis glabrata Benth.) has emerged as a high quality alternative forage for cattle producers in Florida. It is well adapted to the Florida climate and provides high nutritive value forage similar to alfalfa (Medicago sativa L.). However, some researchers have noted that it is slow to establish, poorly adapted to seasonally wet flatwoods soils, and may be invaded by perennial grasses. An experiment of 16 RPP selections, plus the cultivars 'Florigaze' and 'Arbrook', was planted in 1990 at the Univ. of Florida, Agron. Forage Res. Unit, near Hague, FL on a Sparr fine sand (loamy, siliceous, hyperthermic, Grossarenic Paleudult). Plots were harvested for dry matter (DM) yield once in fall 1990, 2x in 1991, 3x in 1992, 2x in 1993, 3x in 1994, and 2x in 1998. They were not sampled for yield in 1995, 1996, and 1997, but herbage was removed with a flail chopper Pr each year. A selection index was devised to include total seasonal yields from each year, amount of spread, and percent RPP ground cover (GC) after 8 yr. Mean annual DM yields over the five harvest years, after the establishment year, for the highest yielding entries ranged between 9.1 and 11.5 Mg ha(-1). Superior lines also had greater than 96% GC 8 yr after establishment. Entries 2, 3, 15, and 18 had equal or superior selection index scores as the released cultivars Florigraze and Arbrook. These entries are being evaluated statewide, including a site on wetter flatwoods soils in south Florida.