Sward responses of rhizoma peanut–bahiagrass mixtures and bahiagrass monocultures in contrasting on-farm environments

Abstract

Incorporating forage legumes into grass swards has the potential to enhance the sustainability of pasture systems and reduce reliance on nitrogen fertilizers. The aim of this study was to assess the on-farm performance of bahiagrass (BG; Paspalum notatum Flüggé)–rhizoma peanut (RP; Arachis glabrata Benth.) mixtures compared to BG monocultures in three diverse environments across Florida. Three forage treatments were employed at all locations: BG in monoculture (Bh), BG + Ecoturf RP (Eco), and BG + Florigraze RP (Flo). Significantly greater herbage accumulation rates were observed for BG + Ecoturf RP (37 kg DM ha⁻¹ day⁻¹, where DM is the dry matter) and BG with Florigraze RP (35 kg DM ha⁻¹ day⁻¹) in comparison with BG in monoculture (30 kg DM ha⁻¹ day⁻¹). Crude protein and in vitro digestible organic matter concentrations were greater for RP binary mixtures compared with monoculture BG across all locations. In North and South Florida, BG + Ecoturf RP exhibited greater RP belowground biomass than BG + Florigraze RP. Additionally, biological N₂ fixation increased linearly as the proportion of RP increased. Integration of RP germplasm Ecoturf and the Florigraze cultivar into BG pastures in North, Central, and South Florida led to increased rates of herbage accumulation and improved herbage nutritive value compared to BG monoculture. Overall, North and South Florida exhibited more favorable responses to the inclusion of RP compared to Central Florida.