Micronutrients in soybean: productivity and economic analysis.

摘要

Field experiment was conducted during crop years 2001/02 and 2002-03 at the Paineira Farm in Coronel Bicaco, Rio Grande do Sul, Brazil, to determine the technical and economic viability of the application of some micronutrients, particularly Mo and Co, in soyabean productivity. The site had been under no-tillage for eight years and the soil type is Hapludox. Soyabean was transplanted during 18 November 2001 and 24 November 2002, with 225 and 190 thousand plant per hectare, for two agricultural years, respectively. The spacing between lines was 0.40 m. Treatments in 2001/02 were: (i) CoMo; (ii) CoMo+Mo: (iii) CoMo+Mo+Mo; (iv) CoMo+Mo+P30; (v) CoMo+B; (vi) B; (vii) Mo; (viii) Mo+Mo; and (ix) Testemunha. In 2002/03 treatments were: (i) CoMo+2x Mo; (ii) CoMo+2x Mo+B; (iii) CoMo+2x Mo+Phitosol PK; (iv) CoMo+2x Fortifol CaB; (v) CoMo+2x Mo+LBE-PT1; (vi) CoMo+2x Mo+P30; (vii) CoMo+2x Mo+stimulate; and (viii) Testemunha. The use of micronutrients, especially Mo and Co, has shown to be a contradictory one in the physical productivity evaluation of the grains through the comparison of averages. However, in most cases, the economic return of the micronutrient application was positive, but it showed its dependence on high productivity and favourable prices at the moment of commercialization.