Título:	Stylosanthes cv. Campo Grande response to Bradyrhizobium inoculation in an Amazon Cerrado Oxisol.
Autoria:	CHAVES, J. da S. SILVA, K. da URQUIAGA, S. FARIAS, E. do N. C. ZILLI, J. E.
Afiliação:	JOSIMAR DA SILVA CHAVES, UNIVERSIDADE FEDERAL DE RORAIMA; KRISLE DA SILVA, CNPF; SEGUNDO SACRAMENTO URQUIAGA CABALLERO, CNPAB; ELIANE DO NASCIMENTO CUNHA, CPAF-RR; JERRI EDSON ZILLI, CNPAB.
Ano de publicação:	2026
Referência:	Agronomy Journal, v. 118, n. 3, 0002-1962, 2026.
Conteúdo:	Species of the genus Stylosanthes show great potential for use in mixed pastures andas green manure due to their symbiotic potential in symbiosis with diazotrophic bac-teria, particularly Bradyrhizobium. These herbaceous legumes can improve pasturequality and contribute to sustainability. This study evaluated performance of Sty-losanthes cv. Campo Grande when inoculated with Bradyrhizobium strains isolatedfrom Oxisols in Roraima, Brazil, versus standard strains. A greenhouse experimenttested 18 new Bradyrhizobium strains isolated from soil alongside two recom-mended strains, including uninoculated and nitrogen-fertilized controls. Also, twofield experiments were conducted using the best-performing greenhouse strain, therecommended strains, and absolute control and nitrogen fertilization (30 kg ha−1 ofN). Variables measured included nodule number and dry nodule mass, root and shootbiomass, and total nitrogen in shoot biomass. The proportion of nitrogen derivedfrom biological nitrogen fixation (percentage of N derived from the atmosphere)was estimated by the 15 N natural abundance method, with Urochloa brizantha asthe reference plant. In the greenhouse, strains ERR 917, ERR 922, ERR 942, ERR1110, and ERR 1173 present great nodulation and dry matter production, identify-ing ERR 917 as optimal for field testing. Inoculation significantly increased bothshoot and root biomass of cv. Campo Grande. Standard strain BR 446T and ERR 917enabled plants to obtain 38%–44% of their total nitrogen from biological nitrogen fix-ation, with inoculated plants accumulating about twice as much nitrogen and biomass versus the uninoculated control (averaging 1900 and 3900 kg ha−1 of dry biomassfor control and inoculated treatments, respectively).Plain Language SummaryThe cultivation of Stylosanthes in association with grass improves pasture qual-ity. Stylosanthes shows great adaptation to the natural conditions of Oxisols butperforms better when soil fertility is improved. Recommended strains of Bradyrhizo-bium and selected native strains contribute to the biomass production of Stylosanthesspp. Biomass gains from Stylosanthes spp. inoculation exceed 100%, with nitrogenaccumulation ranging from 38% to 44%.
Thesagro:	Pastagem Adubação Verde
NAL Thesaurus:	Stylosanthes Bradyrhizobium Amazonia Pasture management Green manures
Palavras-chave:	Amazon Cerrado Oxisol Roraima
Digital Object Identifier:	DOI: 10.1002/agj2.70381
Tipo do material:	Artigo de periódico
Acesso:	openAccess
Aparece nas coleções:	Artigo em periódico indexado (CNPF)