Resumo

LAZZARI, María Aurora; LANDRISCINI, María Rosa  e  ECHANGUE, Marcelo Esteban. Soil and fertilizer nitrogen uptake patterns in malting barley with near seeding fertilization. Cienc. suelo [online]. 2005, vol.23, n.1, pp.69-77. ISSN 1850-2067.

There is a lack of data associated with applications of nitrogen fertilizer to increase yield while not increasing seed protein to levels exceeding those acceptable for malting barley in Buenos Aires province. Field experiments were carried out on eight sites between 1999 and 2000 to determine the effect of nitrogen on the growth, soil and fertilizer uptake, yield and grain nitrogen concentration of barley grown for malting. The treatments were: 0, 30 and 60 kg N ha-1 applied as a whole at plant emergence, 30 and 60 kg N ha-1 applied as a whole at early tillering, and 60 kg N ha-1 applied in split applications of 30 kg N ha-1 each at emergence and at early tillering growth stages. Within each plot there was a microplot to which 15N-labelled urea was applied. Aboveground dry matter production and N uptake were measured at four sampling times from early tillering to physiological maturity from plant samples taken from the microplots. The growth continued to physiological maturity, and maximum growth was usually reached after anthesis, following the period of greater nitrogen uptake. The rate of 30 kg N ha-1 increased yield but not the grain N concentration. The addition of 60 kg N ha-1 affected both yield and grain N concentration. N application time did not affect the dry matter yield nor the N concentration of grain. The variation in soil N uptake between sites was greater than the variation in fertilizer nitrogen uptake. The Nitrogen Harvest Index was not affected by the rate of N application.

Palavras-chave : Hordeum vulgare; Urea; 15N; Soils; Buenos Aires province.

        · resumo em Espanhol     · texto em Espanhol     · Espanhol ( pdf )