RESUMO
Field experiments were conducted on wheat to study the effects of foliar-applied iodine(I) alone, Zn (zinc) alone, and a micronutrient cocktail solution containing I, Zn, Se (selenium), and Fe (iron) on grain yield and grain concentrations of micronutrients. Plants were grown over 2 years in China, India, Mexico, Pakistan, South Africa, and Turkey. Grain-Zn was increased from 28.6 mg kg-1 to 46.0 mg-1 kg with Zn-spray and 47.1 mg-1 kg with micronutrient cocktail spray. Foliar-applied I and micronutrient cocktail increased grain I from 24 µg kg-1 to 361 µg kg-1 and 249 µg kg-1, respectively. Micronutrient cocktail also increased grain-Se from 90 µg kg-1 to 338 µg kg-1 in all countries. Average increase in grain-Fe by micronutrient cocktail solution was about 12%. The results obtained demonstrated that foliar application of a cocktail micronutrient solution represents an effective strategy to biofortify wheat simultaneously with Zn, I, Se and partly with Fe without yield trade-off in wheat.
Assuntos
Biofortificação/métodos , Produção Agrícola/métodos , Iodo/metabolismo , Ferro/metabolismo , Selênio/metabolismo , Triticum/metabolismo , Zinco/metabolismo , China , Fertilizantes/análise , Índia , Iodo/análise , Ferro/análise , México , Micronutrientes/análise , Micronutrientes/metabolismo , Paquistão , Folhas de Planta/química , Folhas de Planta/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Selênio/análise , África do Sul , Triticum/química , Triticum/crescimento & desenvolvimento , Turquia , Zinco/análiseRESUMO
Nitrogen fertilization is a substantial source of nitrogen-containing trace gases that have both regional and global consequences. In the intensive wheat systems of Mexico, typical fertilization practices lead to extremely high fluxes of nitrous oxide (N2O) and nitric oxide (NO). In experiments, lower rates of nitrogen fertilizer, applied later in the crop cycle, reduced the loss of nitrogen without affecting yield and grain quality. Economic analyses projected this alternative practice to save 12 to 17 percent of after-tax profits. A knowledge-intensive approach to fertilizer management can substitute for higher levels of inputs, saving farmers money and reducing environmental costs.