N, P or K doses on the dry matter and crude protein yield in maize and sorghum for silage

• Published in: Pesquisa agropecuária tropical 2017-03, Vol.47 (1), p.53-61
• Main Authors: Damian, Júnior Melo, Ros, Clovis Orlando Da, Silva, Rodrigo Ferreira da, Coldebella, Ivanir José, Simon, Diego Henrique
• Format: Article
• Language: English
• Subjects: AGRICULTURE, MULTIDISCIPLINARY; AGRONOMY; Animal feed; Cereal crops; Corn; Cropping systems; Crops; Cultivation; Dry matter; Feeds; Fertilization; mineral fertilization; Mineral fertilizers; Phosphorus pentoxide; Proteins; Raw materials; Seasons; Silage; Sorghum; Sorghum bicolor; Zea mays
• ISSN: 1983-4063; 1983-4063
• DOI: 10.1590/1983-40632016v4742722

ABSTRACT Maize and sorghum are the main raw materials in the production of silage for animal feed, with mineral fertilization being worthy of note when the goal is to increase gains in the amount and quality of the forage. This study aimed at evaluating the contribution of N, P or K doses to the dry matter and crude protein yield in maize and sorghum grown for silage. The experiments were carried out in a randomized block design, with four replications, during five successive crops of maize (three summer seasons) and sorghum (two off-season). Five doses of N (0 kg ha-1, 50 kg ha-1, 100 kg ha-1, 150 kg ha-1 and 200 kg ha-1), five doses of P2O5 (0 kg ha-1, 40 kg ha-1, 80 kg ha-1, 120 kg ha-1 and 160 kg ha-1) and five doses of K2O (0 kg ha-1, 30 kg ha-1, 60 kg ha-1, 90 kg ha-1 and 120 kg ha-1) were applied to each crop in the same experimental area. The N doses contributed to an increase in the crude protein yield in the five successive crops of maize and sorghum, together with an increase in dry matter and/or protein concentration. Crude protein increased 59.5-312.9 % for both crops. The soils used for the succession cropping system of maize and sorghum for silage had "very high" levels of P and K. Therefore, the P fertilization had no effect on the dry matter or crude protein yield in the first year of cultivation, similarly to the K fertilization during the five successive crop seasons. RESUMO Milho e sorgo são as principais matérias primas na produção de silagem para consumo animal, merecendo destaque a adubação mineral, quando o objetivo for incrementar os ganhos em quantidade e qualidade forrageira. Objetivou-se avaliar a contribuição de doses de N, P ou K na produtividade de massa seca e proteína bruta de milho e sorgo para silagem. Os experimentos foram conduzidos em delineamento de blocos casualizados, com quatro repetições, durante cinco cultivos sucessivos de milho (três safras de verão) e sorgo (duas safrinhas). Foram utilizadas cinco doses de N (0 kg ha-1, 50 kg ha-1, 100 kg ha-1, 150 kg ha-1 e 200 kg ha-1), cinco doses de P2O5 (0 kg ha-1, 40 kg ha-1, 80 kg ha-1, 120 kg ha-1 e 160 kg ha-1) e cinco doses de K2O (0 kg ha-1, 30 kg ha-1, 60 kg ha-1, 90 kg ha-1 e 120 kg ha-1), aplicadas em cada cultivo, na mesma área experimental. As doses de N contribuíram para o aumento da produtividade de proteína bruta nos cinco cultivos sucessivos de milho e sorgo, associado ao aumento de massa seca e/ou da concentração de proteína. O incremento de proteína bruta