Rhizoma Peanut Entries Representing a Range of Growth Habits Differ in Herbage Accumulation, Canopy Characteristics, and Root-Rhizome Mass.

Rhizoma peanut (RP; Arachis glabrata) is a persistent legume in the US Gulf Coast Region, providing an array of ecosystem services. Most current RP cultivars were selected for upright growth and hay production, but RP introductions exist representing a range of growth habits, with potential for other uses. There are limited data describing plant characteristics and forage responses of RP introductions across different environments. The objective was to quantify herbage accumulation (HA), nutritive value, root-rhizome mass, and canopy characteristics for RP introductions and compare them with existing cultivars. Locations included north (NF) and central Florida (CF), and treatments were 15 entries harvested by clipping in July and October and sampled for root-rhizome mass in November 2016. On well-drained NF soils, height at harvest ranged from 20 to 55 cm, and cultivars ‘Arbrook’ and ‘Tito’ were more than 15 cm taller than all but two lines and, along with ‘Peace’, had greatest HA (11.0-11.3 Mg ha^-1 yr^-1). Crude protein ranged from 129-158 g kg^-1 and in vitro digestible organic matter from 597-660 g kg^-1. The tallest entry, Arbrook, had the lowest nutritive value, but this relationship was not consistent across all entries. Root-rhizome mass generally was closely associated with HA. In CF, where soils are relatively poorly drained Spodosols, height ranged only from 11 to 19 cm at harvest, and entry Ona 33, previously thought to be adapted to wetter soils, had greatest HA (9.8 Mg ha^-1). At this location, the most decumbent entry, Chico, had HA of 9.4 Mg ha^-1 and numerically the greatest root-rhizome mass of 10.7 Mg ha^-1. The shorter entries typically had greater nutritive value than taller ones in CF. These data suggest that there is opportunity to select shorter-growing cultivars with high HA, nutritive value, and root-rhizome mass for pasture and ornamental use in different environments.