EFEITO DE IBA E DE RIZOBACTÉRIA NO ENRAIZAMENTO DE MINIESTACAS DE ACÁCIA NEGRA

Abstract

Black wattle is a forest species of great economic importance in the southern of Brazil. Researches for vegetative propagation methods to constitute clonal forests are effective to increase forest productivity. The goal of this work was to evaluate the action of compounds of root promotion in minicuttings of Acacia mearnsii as an alternative to vegetative propagation to the species. The experiment was conducted in July/2018 (winter season), with one negative control, two concentrations of indole butyric acid – IBA (2000 and 4000 mg L-1) and two concentrations of AzoTotal™ (100% e 50%), an inoculant containing Azospirillum brasilense bacterium. In the IBA treatments, the base of minicuttings remained immersed in hydroalcoholic solution 50% for 10 seconds and for the inoculant treatments during 15 minutes. The experiment took place in a greenhouse and after 45 days they were evaluated: the percentage of rooted minicutting; number of roots per minicutting; length of the three largest roots per minicutting; percentage of minicuttings with calluses; percentage of minicuttings survival; percentage of minicutting with budding and percentage of minicutting that kept the leaflets. There was significant difference between treatments considering rooted minicuttings, number of roots by minicutting, length of the three largest roots by minicutting, and there were not observed differences to the other variables analyzed. The use of IBA was more effective for the vegetative propagation process in this species.

Keywords

• acacia mearnsii
• ácido indol butírico
• azospirillum brasilense
• inoculante