Resumo

JUAREZ HERNANDEZ, Ma. De Jesús et al. FORMULATION OF NUTRIENT SOLUTIONS FOR PLANT NUTRITION STUDIES. A PROPOSAL. INCI [online]. 2006, vol.31, n.4, pp.246-253. ISSN 0378-1844.

Several studies in plant nutrition have been done in the past using nutrient formulations. In order to evaluate the effect of one or more nutrients on crop growth, development, yield, quality product as well as nutrient uptake, numerous studies have been carried out, without there being a generally accepted technique for this purpose. Commonly, the main nutrient concentration (anion or cation) is modified, whereas the other nutrients remain at a constant level. Nutrient solutions containing N-NH4+ and N-NO3- are good examples of solutions with parallel changes on the anion and cation nutrient. A number of papers with systematic studies on the chemical characteristics of nutrient solutions and their effect on crops has been analyzed regarding the use of N-NH4+ and/or N-NO3-. These studies did not allow to conclude either about the N-NH4+ or N-NO3- direct effect or on their interaction. A nutrient solution formulation is herein proposed which, according to its factorial design structure based on the combinations of N-NH4+:cations groups with others of similar characteristics of N-NO3-:anions, permits the elaboration of several nutrient solutions (treatments). The treatments allow the direct evaluation of N-NH4+ and N-NO3- effects as well as their interaction, without interference of nutrient solution osmotic pressure or pH.

Palavras-chave : Hidroponía; Relación N-NH4+/N-NO3-; Relación NH4+:cationes; Relación NO3-:aniones.