Boron fertilization and liming for Eucalyptus urograndis cropped on sandy arenosol of Brazilian pampa

ABSTRACT

Boron (B) requirement and its interaction with liming for eucalyptus plantations in sandy soils of Brazilian Pampa are poorly understood. Aiming to diminish this gap, seedlings of Eucalyptus urograndis were grown in pots with Arenosol fertilized with B at rates 0.0, 1.0, 2.5, 5.0 and 10.0 mg B dm⁻³, with and without liming. Results of shoot and root dry matter and stem diameter did not evidence the necessity of B fertilization. With the exception of the 1.0 mg B dm⁻³+lime, all other B-fertilized treatments promoted visual symptoms of toxicity, which were partially mitigated by liming. Liming exacerbated the B loss by leaching, but after five months, limed soils had higher content of available B and their plants had higher B concentration in shoots and roots. For our conditions, application of ≥2.5 mg B dm⁻³ can cause serious toxic injuries to plants and enlarge dramatically the B losses leaching.

KEYWORDS:

• Boron leaching
• toxicity
• dry mass yield
• lime

Funding

This work was conducted with financial support of FAPERGS (process 1013351/07-2010) and CNPq (process 481305/2010-6).