Dolomite and phosphogypsum surface application effects on annual crops nutrition and yield

• Grant number: 08/00293-0
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• Start date: February 01, 2008
• End date: February 29, 2008
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Rogério Peres Soratto
• Grantee: Rogério Peres Soratto
• Host Institution: Faculdade de Ciências Agronômicas (FCA). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Brazil has extensive area with acid soils. Using phosphogypsum and soil acidity tolerant cultivars are alternatives to crop establishment in no-till system without previous limestone incorporation in many agricultural soils of Brazil. However, it remains unknown how phosphogypsum and limestone surface application affects rice (Oryza sativa L.) and common bean (Phaseolus vulgaris L.) nutrition and yield under a no-till system. A field experiment was conducted in a Haplortox, previously cultivated under conventional tillage, in Botucatu, São Paulo State, Brazil. Treatments included four dolomitic limestone rates (0, 1,100, 2,700, and 4,300 kg ha-1), two phosphogypsum rates (0 and 2,100 kg ha-1), and two upland rice cultivars (Caiapó and IAC 202), in 2002/2003, and two bean cultivars (Pérola and Carioca), in 2003/2004. Both amendments were applied on the surface, without soil incorporation. The content of Ca, Mg, and Mn in flag leaves and rice yield increased with limestone surface application. Liming increased the shoot dry matter of rice cv. IAC 202. Phosphogypsum increased S contents in leaves of both rice cultivars, and resulted in higher grain yield in the cv. Caiapó. Liming increased K contents in leaves of both bean cultivars. In the absence of phosphogypsum, liming increased S contents and grain yield of bean. Content of Mg in leaves was reduced by phosphogypsum in lower limestone rates. In phosphogypsum presence, liming reduced Zn contents in leaves and increased bean shoot dry matter. Phosphogypsum increased Ca and S, and reduced Mg contents in bean leaves. Using soil acidity tolerant cultivars promoted higher crop yields in no-till systems establishment, even when the effective soil amelioration had not yet been achieved. (AU)