Premium
Herbage responses and nitrogen agronomic efficiency of bahiagrass–legume mixtures
Author(s) -
Santos Erick R. S.,
Dubeux Jose C. B.,
Jaramillo David M.,
Garcia Liza,
Mackowiak Cheryl L.,
Blount Ann R. S.,
PereiraNeto Jose D.,
Queiroz Luana M. D.,
RuizMoreno Martin
Publication year - 2020
Publication title -
agronomy journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.752
H-Index - 131
eISSN - 1435-0645
pISSN - 0002-1962
DOI - 10.1002/agj2.20278
Subject(s) - paspalum notatum , agronomy , forage , monoculture , legume , biology , pasture , dry matter , human fertilization
Bahiagrass ( Paspalum notatum Flüggé) is the most utilized forage in Florida and requires N fertilization to optimize production. Integrating legumes into bahiagrass pastures may reduce N fertilizer inputs and improve forage nutritive value. This 2‐yr, 2‐location, on‐farm study established two legumes, alfalfa ( Medicago sativa L.) or rhizoma peanut (RP; Arachis glabrata Benth.), in mixtures with bahiagrass. We compared bahiagrass–legume mixtures + 45 kg N ha −1 harvest −1 with their non‐N fertilized monocultures and with bahiagrass + 90 kg N ha −1 harvest −1 (N‐fertilized bahiagrass). Treatments were bahiagrass, N‐fertilized bahiagrass, bahiagrass–alfalfa, bahiagrass–RP, alfalfa, and RP. Variables analyzed included herbage accumulation (HA), botanical composition, forage N concentration, forage total N aboveground (TNAG), and N agronomic efficiency. Mixtures and N‐fertilized bahiagrass resulted in similar cumulative HA (10,400 kg dry matter [DM] ha −1 yr −1 , on average) and they were greater than all other treatments (4,190 kg DM ha −1 yr −1 , on average). Alfalfa and RP represented low proportions of the mixed swards, with alfalfa proportion being as high as 16.1% and as low as 1.6%. Rhizoma peanut greatest proportion was 2.1% and the lowest was 0.5%. Mixtures and N‐fertilized bahiagrass maintained similar N concentrations, but they were consistently lower than legume monocultures. The N‐fertilized bahiagrass and mixture treatments resulted in the greatest TNAG in four out of the six sampling dates. The AE N of mixtures was typically greater than N‐fertilized bahiagrass. Since legumes had low proportion in mixtures, 45 kg N ha −1 harvest −1 was the upper limit for reaching maximum HA in bahiagrass.