Doses of NPK formulations combined with humic substance at sowing in barley cultivars

• Published in: Revista brasileira de engenharia agrícola e ambiental 2018-10, Vol.22 (10), p.683-688
• Main Authors: Szeuczuk, Kathia, Mendes, Marcelo C., Stadler, Alan J., Pagliosa, Eduardo S., Schroeder, Bruno, Muller, Marcelo M. L.
• Format: Article
• Language: English
• Subjects: AGRICULTURAL ENGINEERING; ENVIRONMENTAL SCIENCES
• ISSN: 1415-4366; 1807-1929; 1807-1929
• DOI: 10.1590/1807-1929/agriambi.v22n10p683-688

ABSTRACT This study aimed to evaluate NPK formulations used in fertilization at sowing associated with and without humic substances (HS) in terms of the agronomic characteristics and grain quality for malt from the barley cultivars BRS Brau and BRS Elis, focusing on the agricultural years 2015 and 2016 in Guarapuava, PR. The experimental design was a randomized block, in a factorial 5 x 2 format, with five fertilizations: 0 kg ha-1 (control); 100 kg ha-1 of NPK; 100 kg ha-1 NPK + HS; 250 kg ha-1 of NPK; and 250 kg ha-1 NPK + HS, using two barley cultivars, BRS Brau and BRS Elis, replicated four times. The variables evaluated were hectoliter weight, grain yield, malt quality by means of sort 1, 2 and 3, and the protein percentage. The data evaluated were submitted to joint variance analyses for the agricultural crops, and the means were compared through non-orthogonal contrasts. The use of humic substances in NPK formulations provides an increase in grain yield, and its effect is observable in the lower doses of NPK + HS formulations. The lower dose of NPK formulation combined with the humic substance reduced class 1 and increased class 3 in agricultural crops from the years 2015 and 2016. The 2016 crop, with favorable climatic conditions, presented improved hectoliter mass, grain yield and quality of the barley grains, based on commercial grade. RESUMO Objetivou-se avaliar doses de formulado NPK em adubação de semeadura associadas ou não à substância húmica (SH), nas características agronômicas e qualidade de grãos para malte, nas cultivares de cevada BRS Brau e BRS Elis, nas safras agrícolas de 2015 e 2016, em Guarapuava, PR. O delineamento experimental foi em blocos ao acaso, em esquema fatorial 5 x 2, sendo cinco adubações: 0 kg ha-1 (controle); 100 kg ha-1 de NPK; 100 kg ha-1 de NPK + SH; 250 kg ha-1 de NPK; 250 kg ha-1 de NPK + SH, em duas cultivares de cevada BRS Brau e BRS Elis, em quatro repetições. Foram avaliadas a massa hectolítrica e produtividade de grãos e a qualidade de malte por meio das classes 1, 2 e 3 de grãos e teor de proteína. Os dados avaliados foram submetidos à análise de variância conjunta para as safras agrícolas e as médias comparadas por meio de contrastes não-ortogonais. A utilização de substância húmica em formulados NPK proporcionou aumento na produtividade de grãos, sendo o seu efeito notado nas menores doses do formulado 100 NPK + SH. A menor dose do formulado NPK associada à substância húmica reduziu a classe 1 e aumentou