Sources and application methods of boron in Eucalyptus crop

Abstract

Cerrado soils have low boron (B) content, making supplementation of this element through fertilization via soil and/or leaf is a common practice. It is therefore important to establish the best mode of application and source of B for the proper development of eucalyptus. Thus, the objective of this study was to compare the effect of B sources with high and low solubility on eucalyptus cultivation and to examine the effect of foliar application of the micronutrient. The experiment was conducted in an area located at 20 o 34' S latitude and 51 o 50' W longitude with an altitude of 305 m during the period from January 2012 to February 2014. The experiment was set up using a randomised complete block design with six treatments and five replications, in a 3 x 2 factorial scheme, consisting of 0 kg ha -1 of B, 1 kg ha -1 of B using boric acid as a source (high solubility, 17% B) or 1 kg ha -1 of B using borogran as a source (low solubility, 10% B), applied to the planting furrow, with or without foliar application of 0.5% boric acid in a solution with a volume of 250 L ha -1 . Except for the case of foliar B application, there was an increase in plant height in treatments that received the micronutrient at planting, which differed significantly from the control. However, both sources, independent of solubility, exhibited similar results. The two foliar B applications were sufficient to cause an increase in plant height when compared to treatments without B application at planting, at 21 months. At 24 months after planting, an increase in leaf B was observed in treatments with foliar application. However, this did not improve growth, diameter at breast height (DBH) or timber volume of the eucalyptus clone. Both the application of B at planting (independent of the source used) and the foliar application of the element were sufficient to reduce the symptoms of B deficiency. With respect to the sources used at planting, at a dose of 1 kg ha de 3 x 2, sendo: 0 kg ha -1 de B, 1 kg ha -1 de B utilizando como fonte o ácido bórico (alta solubilidade, 17% B) ou1 kg ha -1 de B utilizando como fonte o borogran (baixa solubilidade, 10% B), aplicados no sulco de plantio, com ou sem aplicações de ácido bórico via foliar na dose de 0,5% de ácido bórico na calda com volume de 250 L ha -1 . Com a omissão de B via foliar houve incremento em altura de plantas nos tratamentos que receberam a aplicação do micronutriente no plantio, diferindo significativamente da testemunha. Porém, ambas as fontes, independente da solubilidade, apresentaram resultados semelhantes. As duas aplicações de B via foliar foram suficientes para que houvesse incremento em altura de plantas, quando comparadas aos tratamentos que não receberam aplicação de B no plantio, aos 21 meses. Aos 24 meses após o plantio foi constatado aumento no teor foliar de B nos tratamentos que receberam aplicação foliar. No entanto, esta não incrementou o crescimento, DAP e volume de madeira do clone de eucalipto. A aplicação de B no plantio, independente da fonte utilizada, ass...

Boron in Preventing of Shoot Dieback on Eucalyptus Benthamii Grown in Soil With Different Water Regimes

“…A similar result was observed by Celestrino et al (2015) in Eucalyptus urophylla, which 24 months after planting presented an increase in B concentration in the leaves in response to foliar application, however, there was no improvement in growth, diameter or volume of wood.…”

Soil Chemical Attributes, Biometric Characteristics, and Concentrations of N and P in Leaves and Litter Affected by Fertilization and the Number of Sprouts per the Eucalyptus L’Hér. Strain in the Brazilian Cerrado

“…Under the same soil and climatic conditions, in the first cycle of Eucalyptus, Gazola et al [29] verified that the maximum yield of Eucalyptus was obtained at 21 months of age with the application of 71 kg ha −1 of N, 100 kg ha −1 of P 2 O 5 , and 125 kg ha −1 of K 2 O. Celestrino [33] observed positive results for plant height, DBH, and VW with a dose of 1 kg ha −1 of B applied to the Eucalyptus.…”

Management of boron fertilization in eucalyptus cultivated in the low altitude Cerrado region in Entisol

“…Foliar B applications reduced the percentage of tree forks until 42 months after planting (Table 7); however, there was no interaction between soil and foliar application, according to results obtained by Celestrino et al (2015) at 24 months after planting. The authors also observed that even with the omission of B at planting, foliar applications (total of 0.425 kg ha -1 of B) were sufficient to reduce 35% of tree forks, when compared to the control group.…”