Rooting of juvenile cuttings of Brazil nut trees using indolebutyric acid in sub-irrigation chamber

Abstract

The sexual propagation of Brazil nut (Bertholletia excelsa Humb. & Bonpl.) is limited by several factors, including slow and irregular germination, unevenness in root and shoot emergence, and a strategy to overcome these limitations is vegetative propagation. The objective of this study is to evaluate the rooting of Brazil nut cuttings using different concentrations of indolebutyric acid (IBA) in a subirrigation system. The study adopted a completely randomized block design with five concentrations of IBA (0, 1000, 2000, 3000, and 4000 mg L-1). The donor plants of the vegetative material were obtained from seeds of trees selected as highly productive parent plants. Cuttings with approximately 6 cm were obtained from the basal and middle sections of the shoot and contained one pair of nodes and one fully developed leaf. The percentage of survival, callus formation, rooting, and sprouting was determined at 105 days after rooting. IBA improved the analyzed characteristics for the development of Brazil nut plants. The IBA concentration of 1000 mg L-1 provided the highest percentage of survival, rooting, and callus formation. Juvenile cuttings showed a higher rate of survival (69.7%), rooting (49.1%), and callus formation (30.2%) at IBA concentrations between 1.9 and 2.3 g L-1.