EFFECT OF THE FORM AND CONCENTRATION OF N ON THE GROWTH AND MINERAL COMPOSITION OF OLIVE SEEDLINGS

The influence of three salts (KNO₃, NH₄NO₃ and (NH₄)₂SO₄) in different concentrations, on the growth and mineral composition of olive seedlings cultured in vitro and in greenhouse conditions, was studied.

The best growth was obtained in in vitro culture through the applications of NH₄NO₃, in concentrations of 10 and 20 mM of N. Addition of (NH₄)₂SO₄ clearly damaged the seedlings and increased the contents of S in the seedlings’ tissues.
All the treatments led to a direct relationship between concentration of N in the medium and N in the seedling tissues, however the N-increases were lowest for KNO₃ and highest for ammonium applications, especially for NH₄NO₃.

In greenhouse conditions all the N-treatments significantly increased the growth of the seedlings but no significant differences between N-salts were observed except for (NH₄)₂SO₄ at the highest concentration.
Treatment with (NH₄)₂SO₄ did not induce any symptom of toxicity in the seedlings, in contrast to the behaviour of in vitro seedlings.
The treatments did not cause significant changes in the mineral composition of the seedling tissues.
These circumstances were related to the fact that an oxidation process (nitrification) was produced from N-NH₄ to N-NO₃ in the nutritive solutions in the containers.

II International Symposium on Olive Growing

R. Sarmiento, J.L. García, C. Mazuelos, J. Liñán, A. Troncoso

olive, embryos, seedlings, in vitro, nitrogen, nutrition, growth

https://doi.org/10.17660/ActaHortic.1994.356.33