Tuesday, September 11, 2007

Cotton response to doses and methods of phosphorus application in no-till system in the Brazilian savannah

Mrs. Maria da Conceição S. Carvalho, Brazilian Agricultural Research Corporation - Embrapa Cotton, Rodovia BR-153, Km 04, Caixa Postal 714, CEP 74001-970, Goiânia, Brazil, Mr. Wilson M. Leandro, Universidade Federal de Goiás, Campus Samambaia - Rodovia Goiânia/Nova Veneza, Km 0 - Caixa Postal 131, CEP 74001-970, Goiânia, Brazil, and Ms. Kézia de A. Barbosa, Fundação GO, Alameda Zeca Valeriano, 2932 Parque Industrial Ipeguary, Santa Helena de Goiás, Brazil.

Due to the inherently low content and high degree of P fixation in Brazilian Savannah soils, supplemental P is required to meet crop demands. The goal of this study was to evaluate the cotton (Gossypium hirsutum L.) response to doses of phosphorus (60, 120, 180 and 240 kg ha-1 of P2O5) on broadcast application and in the seed row, in clay soils with different P contents. The field experiment was conducted in the State of Goiás during the seasons 2003/2004, 2004/2005, and 2005/2006 in a 4 x 2 +1 (control) factorial scheme in randomized complete blocks design with four replications. When surface soil P was lower than 4 mg dm-3 (Mehlich 1) cotton yield increased until the dose of 120-140 kg ha-1 of P2O5, but there was no yield response when soil P was 14 mg dm-3. The data indicate that, in no-till system, soluble phosphate fertilizers can be used on broadcast application or in the seed row. Broadcast applications are desirable when high rates of P fertilizer are used.

See more of Agronomy and Cotton Farming Systems Poster Session
See more of Agronomy and Cotton Farming Systems

See more of The World Cotton Research Conference-4 (September 10-14, 2007)