3 results

Kinetic parameters of silicon uptake by rice cultivars

Priscila Oliveira Martins, Carlos Alexandre Costa Crusciol, Cristiane Pilon

01/Feb/2012

Silicon is considered an important chemical element for rice, because it can improve tolerance to biotic and abiotic stress. However, in many situations no positive effect of silicon was observed, probably due to genetic factors. The objective of this research was to monitor Si uptake kinetics and identify responses of rice cultivars in terms of Si uptake capacity and use. The experiment was carried out in a greenhouse of the São Paulo State University (UNESP), Brazil. The experiment was arranged […]

Phosphorus and root distribution and corn growth as related to long-term tillage systems and fertilizer placement()

Sérgio Ely Valadão Gigante de Andrade Costa, Edicarlos Damaceno de Souza, Ibanor Anghinoni, João Paulo Cassol Flores, Eduardo Giacomelli Cao, Marquel Jonas Holzschuh

01/Oct/2009

Soil and fertilizer management during cultivation can affect crop productivity and profitability. Long-term experiments are therefore necessary to determine the dynamics of nutrient and root distribution as related to soil profile, as well as the effects on nutrient uptake and crop growth. An 18-year experiment was conducted at the Federal University of Rio Grande do Sul State (UFRGS), in Eldorado do Sul, Brazil, on Rhodic Paleudult soil. Black oat and vetch were planted in the winter and corn in the […]

Uptake kinetics and nutritional efficiency for K+, Ca2+ and Mg2+ in four eucalypt clones seedlings

Augusto Miguel Nascimento Lima, Júlio César Lima Neves, Ivo Ribeiro Silva, Fernando Palha Leite

01/Dec/2005

The use of mechanistic models based on principles of solute transport may be of great utility to estimate, for example, the impact of eucalypt forest cultivation on the pools and fluxes of nutrient in soils. Among the parameters required by such models are the values of the ion absorption kinetics constants Vmax, Km and Cmin. Thus, the objective of this study was to determine the values of Vmax, Km and Cmin for K, Ca and Mg, as well as to […]