A smart controlled-release fertilizer improved soil fertility but not olive tree physiology and yield Artigo de Conferência uri icon

resumo

  • The use of a controlled-release fertilizer (CRF) was studied in a traditional rainfed olive grove in the northeast of Portugal where precipitation is very irregular, particularly in the spring. The objective of the study was to assess whether a CRF can improve the olive tree' s performance compared to a conventional nitrogen (N) fertilizer (CF), by supplying N gradually and reducing the risk of potential N loss from leaching. The fertilized treatments showed better plant N nutritional status, which resulted in enhanced net photosynthesis and higher leaf concentrations of total soluble sugars, chlorophylls and soluble proteins which, in turn, increased olive yield by 43% in comparison to the unfertilized control. Meanwhile, CRF show some advantages over the CF, although by an unexpected effect. Not in a direct way, by improving trees performance, but by enhancing soil fertility. The CRF treatments showed higher leveis of inorganic N in the soil by autumn, an aspect that at the outset could be interpreted as nega tive, since it could lead to N loss by leaching, but that proved to be a factor that may be behind the increase in the ol'ganic carbon, kjeldahl nitrogen and glomalin-related soil proteins. Thus, the availability of soil inürganlc-N in the autumn, in a climate in which excess precipitation and the risk of ieaching usually only occur in winter, led to weeds growth that seem to act as a catch crop, capturing residual inorganic N. Additionally, they contribute to protect the soil from erosion and to increase soi! organic matter, aspects that can benefit the agrosystem in the long-term.

autores

  • Margarida Maria Pereira Arrobas Rodrigues
  • E. Silva
  • Arrobas, M.
  • Alexandre F. Gonçalves
  • Martins, S.
  • Luis Pinto
  • Luís Carlos Rodrigues Carvalho Pinto
  • Brito, C.
  • José M. Moutinho-Pereira
  • Pinto, M.A.
  • Carlos Correia
  • Rodrigues, M.A.

data de publicação

  • janeiro 1, 2021