POTASSIUM FERTILIZATION OF SOYBEAN, PEARL MILLET, AND COTTON IN A NO-TILL ROTATION SYSTEM IN THE CERRADO REGION DOSES E FORMAS DE APLICAÇÃO DA ADUBAÇÃO POTÁSSICA NA ROTAÇÃO SOJA, MILHETO E ALGODÃO EM SISTEMA PLANTIO DIRETO

• Main Authors: Maria da Conceição Santana Carvalho, Tiago Gomes da Silva Mesquita, Wilson Mozena Leandro, Juarez Patrício de Oliveira Júnior, Alberto Carlos de Campos Bernardi, Pedro Luiz de Freitas
• Format: Article
• Language: English
• Published: Universidade Federal de Goiás 2009-03-01
• Series: Pesquisa Agropecuária Tropical
• Subjects: Glycine max; Pennisetum; Gossypium hirsutum; qualidade da fibra; eficiência agronômica
• Online Access: http://www.revistas.ufg.br/index.php/pat/article/view/3519
• ISSN: 1983-4063

&lt;p class="MsoNormal" style="text-align: justify; line-height: 200%"&gt;&lt;span style="font-size: 11pt"&gt;&lt;!--[if !supportEmptyParas]--&gt;&lt;/span&gt;&lt;/p&gt; &lt;!-- @page { margin: 2cm } P { margin-bottom: 0.21cm } --&gt; &lt;p style="margin-bottom: 0cm; font-style: normal; line-height: 120%; text-decoration: none;" lang="pt-BR" align="justify"&gt;&lt;span style="color: #000000;"&gt;&lt;span style="font-family: Times New Roman,serif;"&gt;&lt;span style="font-size: small;"&gt;The main objective of this study was to evaluate the efficiency of potassium fertilizer application, as related to rate, placement (in-row, broadcast, and split topdress) and time (before sowing, at sowing, and topdressing), in a soybean, pearl millet, and cotton no-till rotation system, in a typic dystrophic Red Latosol (Hapludox), in Turvelândia, Goiás State, Brazil (17&lt;sup&gt;o&lt;/sup&gt;51’S, 50&lt;sup&gt;o&lt;/sup&gt;18’W). The experimental design was a factorial randomized block, with 4 replications. Potassium source was KCl. Potassium was applied to soybean (0 kg ha&lt;sup&gt;-1&lt;/sup&gt;, 30 kg ha&lt;sup&gt;-1&lt;/sup&gt;, 60 kg ha&lt;sup&gt;-1&lt;/sup&gt;, and 180 kg ha&lt;sup&gt;-1 &lt;/sup&gt;of K&lt;sub&gt;2&lt;/sub&gt;O&lt;strong&gt;) &lt;/strong&gt;in the planting row or broadcasted before sowing, at sowing, or topdressed. For cotton, the K rates were 0 kg ha&lt;sup&gt;-1&lt;/sup&gt;, 60 kg ha&lt;sup&gt;-1&lt;/sup&gt;, 120 kg ha&lt;sup&gt;-1&lt;/sup&gt;, and 240 kg ha&lt;sup&gt;-1&lt;/sup&gt; of K&lt;sub&gt;2&lt;/sub&gt;O, applied before sowing and placed in the planting row, with none or one topdressing, or split in two applications. The pre-planting cotton K was applied in the pearl millet. There was no effect of potassium fertilization on soybean yield. As a cover crop, pearl millet used, more efficiently, the 60 kg ha&lt;sup&gt;-1 &lt;/sup&gt;of K&lt;sub&gt;2&lt;/sub&gt;O rate. Results showed that the best cotton agronomic efficiency was obtained with 146 kg ha&lt;sup&gt;-1 &lt;/sup&gt;of&lt;sup&gt; &lt;/sup&gt;K&lt;sub&gt;2&lt;/sub&gt;O, supplied before sowing. Results also showed positive effects of potassium fertilization on cotton fiber quality.&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="text-indent: 1cm; margin-bottom: 0cm; font-style: normal; line-height: 120%; text-decoration: none;" lang="pt-BR" align="justify"&gt; &lt;/p&gt; &lt;p style="margin-bottom: 0cm; font-style: normal; line-height: 120%; text-decoration: none;" lang="pt-BR" align="justify"&gt;&lt;span style="color: #000000;"&gt;&lt;span style="font-family: Times New Roman,serif;"&gt;&lt;span style="font-size: small;"&gt;KEY-WORDS:&lt;em&gt; Glycine max&lt;/em&gt;; &lt;em&gt;Pennisetum&lt;/em&gt;;&lt;em&gt; Gossypium hirsutum&lt;/em&gt;; fiber quality; agronomic efficiency.&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;<br>&lt;p class="MsoBodyText3" style="text-align: justify; line-height: 200%"&gt;&lt;!-- @page { margin: 2cm } P { margin-bottom: 0.21cm } --&gt; &lt;p style="margin-bottom: 0cm; font-style: normal; line-height: 120%; text-decoration: none;" lang="pt-BR" align="justify"&gt;&lt;span style="color: #000000;"&gt;&lt;span style="font-family: Times New Roman,serif;"&gt;&lt;span style="font-size: small;"&gt;Este estudo teve como objetivo avaliar a eficiência da adubação potássica, com relação às doses, modos (sulco, a lanço e parcelada) e épocas de aplicação (pré-semeadura, semeadura e cobertura), na sucessão de culturas soja-milheto-algodoeiro, cultivadas em sistema plantio direto, em Latossolo Vermelho, no município de Turvelândia, Goiás (17&lt;sup&gt;o&lt;/sup&gt;51’S, 50&lt;sup&gt;o&lt;/sup&gt;18’W). O delineamento experimental adotado foi o de blocos casualizados, com quatro repetições, em esquema fatorial. A fonte de potássio utilizada nas adubações foi o cloreto de potássio. Na soja, os tratamentos utilizados foram doses de K&lt;sub&gt;2&lt;/sub&gt;O (0 kg ha&lt;sup&gt;-1&lt;/sup&gt;, 30 kg ha&lt;sup&gt;-1&lt;/sup&gt;, 60 kg ha&lt;sup&gt;-1&lt;/sup&gt; e 180 kg ha&lt;sup&gt;-1&lt;/sup&gt;), aplicadas em pré-semeadura (a lanço) e na semeadura (no sulco), com e sem cobertura. Na cultura do algodoeiro, os tratamentos foram doses de K&lt;sub&gt;2&lt;/sub&gt;O (0 kg ha&lt;sup&gt;-1&lt;/sup&gt;, 60 kg ha&lt;sup&gt;-1&lt;/sup&gt;, 120 kg ha&lt;sup&gt;-1&lt;/sup&gt; e 240 kg ha&lt;sup&gt;-1&lt;/sup&gt;), aplicadas em pré-semeadura (a lanço) e na semeadura (no sulco), com 0, 1 ou 2 coberturas. A adubação em pré-semeadura foi realizada no milheto. Não houve efeito da adubação potássica sobre a produtividade da cultura da soja. O milheto, como cobertura do solo, aproveitou, mais eficientemente, a dose de 60 kg ha&lt;sup&gt;-1 &lt;/sup&gt;de K&lt;sub&gt;2&lt;/sub&gt;O, aplicada na cultura da soja. Para a cultura do algodoeiro, a maior eficiência agronômica foi obtida com dose de 146 kg ha&lt;sup&gt;-1&lt;/sup&gt; de K&lt;sub&gt;2&lt;/sub&gt;O, em pré-semeadura. Os resultados indicaram, também, que houve efeito positivo da adubação potássica sobre a qualidade da fibra do algodão.&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="text-indent: 1cm; margin-bottom: 0cm; font-style: normal; line-height: 120%; text-decoration: none;" lang="pt-BR" align="justify"&gt;&lt;span style="color: #000000;"&gt; &lt;/span&gt;&lt;/p&gt; &lt;p style="margin-bottom: 0cm; font-style: normal; line-height: 120%; text-decoration: none;" lang="pt-BR" align="justify"&gt;&lt;span style="color: #000000;"&gt;&lt;span style="font-family: Times New Roman,serif;"&gt;&lt;span style="font-size: small;"&gt;PALAVRAS-CHAVE: &lt;em&gt;Glycine max&lt;/em&gt;; &lt;em&gt;Pennisetum&lt;/em&gt;; &lt;em&gt;Gossypium hirsutum&lt;/em&gt;; qualidade da fibra; eficiência agronômica.&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;&lt;/p&gt;