Nitrogen and potassium in the cultivation of piata grass in Brazilian cerrado soil/Nitrogenio e potassio no cultivo do capim-piata em solo do cerrado Brasileiro

• Published in: Revista brasileira de engenharia agrícola e ambiental Vol. 20; no. 11; p. 984
• Main Authors: de Morais, Lea P.V.X.C, Bonfim-Silva, Edna M, Pacheco, Adriano B, de Abreu, Joadil G, da Silva, Tonny J.A, Polizel, Analy C
• Format: Journal Article
• Language: English
• Published: ATECEL--Associacao Tecnico Cientifica Ernesto Luiz de Oliveira Junior 01.11.2016
• Subjects: Brasil
• ISSN: 1415-4366; 1807-1929
• DOI: 10.1590/1807-1929/agriambi.v20n11p984-989

This study aimed to evaluate the production and mineral nutrition of Piata grass as a function of nitrogen and potassium fertilization in Oxisol collected in the Cerrado. The experiment was carried out in a greenhouse, the experimental design was completely randomized, in a 5 x 5 factorial scheme, corresponding to five nitrogen doses (0, 100, 200, 300 and 400 mg [dm.sup.-3] of N) and five potassium doses (0, 90, 180, 270 and 360 mg [dm.sup.-3] of [K.sub.2]O), with four replicates. Three cuts of the shoots were performed every 30 days. Chlorophyll index, dry mass of shoots and roots, and nitrogen and potassium contents in the leaves were evaluated. The dry mass of shoots showed interaction between nitrogen and potassium in the three cuts; in the second and third cuts, it had maximum production at the nitrogen and potassium doses of 254 and 158 mg [dm.sup.-3], in the second, and 250 and 306 mg [dm.sup.-3] in the third, respectively. The nitrogen and potassium contents are influenced as a function of nitrogen and potassium fertilization isolated by factor. The nitrogen and potassium ratio in the Piata grass crop was around 1:1. Key words: Brachiaria brizantha nitrogen content potassium content N:K ratio in plants Objetivou-se avaliar a producao e a nutricao mineral do capim piata em funcao da adubacao nitrogenada e potassica em Latossolo Vermelho coletado no Cerrado. Realizouse o experimento em casa de vegetacao, o delineamento experimental foi inteiramente casualizado em esquema fatorial de 5 x 5 sendo cinco doses de nitrogenio (0, 100, 200, 300 e 400 mg [dm.sup.-3]) e cinco doses de potassio (0, 90, 180, 270 e 360 mg [dm.sup.-3]), com quatro repeticoes. Realizaram-se tres cortes da parte aerea a cada 30 dias. Foram avaliados o indice de clorofila, a massa seca da parte aerea e das raizes, a concentracao de nitrogenio e de potassio, nas folhas. A massa seca da parte aerea apresentou interacao entre o nitrogenio e o potassio nos tres cortes sendo que no segundo e no terceiro apresentou maxima producao nas doses de nitrogenio e potassio, de 254 e 158 mg [dm.sup.-3] no segundo e de 250 e 306 mg [dm.sup.-3] no terceiro, respectivamente. As doses de nitrogenio e de potassio apresentaram interacao significativa para a massa seca da parte aerea do capim piata, nos tres cortes. As concentracoes de nitrogenio e potassio sao influenciadas em funcao da adubacao nitrogenada e potassica isolada por fator. A relacao de nitrogenio e potassio no capim piata e de 1:1. Palavras-chave: Brachiaria brizantha concentracao de nitrogenio concentracao de potassio relacao N:K nas plantas